This document provides technical data for the erection of a 500 MW steam turbine from KWU design. It includes specifications for the turbine construction including cylinders, valves, speeds, pressures, temperatures, and limitations. Key details include it being a three cylinder reheat condensing turbine with 17 reaction stages in the high pressure cylinder and 12 reaction stages per flow in the double flow intermediate pressure cylinder. The rated steam conditions and permissible operating values are also provided.

1. ERECTION
MANUAL
STEAM TURBINE
500 MW
(KWU DESIGN)
DOCUMENT NO. TS-T1-08
Bharat Heavy Electricals Limited
POWER SECTOR
TECHNICAL SERVICES (HQ)
NOIDA
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 1

2. FOREWORD
I am glad that Power Sector - Technical Services ( Head Quarters),
Noida has brought out this erection manual of 500 MW steam
turbine (KWU design) being produced by BHEL. This manual lays
emphasis on site optimisation techniques which aims at uniform
erection practices, improvement in quality, reduction in time cycle
and saving in cost.
I am sure, this manual will form the basis for site erection activities
so that the organisation can derive
full benefit out of this. It is
needless to emphasize that upgrading of technology is a continuous
process and we have to review our methods of working and make
suitable changes, wherever required.
New Delhi
Bharat Heavy Electricals Limited
Rev 00, 7-98
(K P Mathur)
Executive Director
(PEM & TS)
T1-08-0801G
Page No. 2

3. PREFACE
The Erection Manual for 500 MW Steam Turbine (KWU design)
manufactured by BHEL
for Thermal Power Stations has been
prepared by a team of BHEL engineers having long experience in
Erection & Commissioning, Design, Quality control of steam turbines.
This dedicated team has been drawn from regional erection group,
designed department of manufacturing units, PS-Q & TS-HQ,
Noida.
The manual carries general description of steam turbine, erection
procedure, special instruction, general instructions, and various other
technical instructions with an intention to establish an uniform
approach for erection of steam turbine.
The Erection Manual provides broad based guide line for erection of
steam turbine.
Product standard, technical circulars & BHEL
drawings for the specific project will precede the instructions and
guidelines furnished in this manual. Project specific document will be
generated by region concerned. This document is generated as a
standard Erection Manual for 500 MW fixed pedestal type steam
turbine with spring loaded foundation.
The work done by TASK FORCE is commendable. Feed-back and
suggestions are welcome for the improvement of this Erection
Manual to bringing down the cycle time with quality.
BHEL reserves the right to suggest alternative
necessity arises at site due to local site conditions .
NOIDA
SNO
DESCRIPTION
Bharat Heavy Electricals Limited
Rev 00, 7-98
procedure
if
(BABOO RAM)
GENERAL MANAGER(TS&Q)
INSTRUCTION NO
T1-08-0801G
Page No. 3

4. 1
TECHNICAL DATA
T 1- 08-0101G
2
INSTRUCTION FOR HANDLING AND
STORAGE OF TURBINE
T 1-08-0202G
3
ERECTION SEQUENCE
T 1-08-0303G
4
ERECTION PROCEDURE
T 1-08-0404G
5
GROUTING PROCEDURE
T 1- 08-0505G
6
ASSEMBLY OF IP MODULE AT SITE
T 1-08-0606G
7
SEALING AND ANTISEIZING COMPOUNDS
T 1-08-0707G
8
CRITICAL ACTIVITIES
T 1-08-0808G
9
SPRING LOADED FOUNDATION
T 1- 08-0909G
10
ERECTION OF PIPING
T 1-08-1010G
11
SPECIFICATION FOR GAS HEATING DEVICE
T 1-08-1111G
12
SPECIFICATION FOR BREECH NUT HEATING
DEVICE
T 1-08-1212G
13
SPECIFICATION FOR THERMAL INSULATION
T1-08-1313 G
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 4

5. The following codification system is used for numbering of instructions and the
codification of Log Sheets is as per FQA document.
XX
Alpha
X
Numeric
XX
Numeric
XX
Numeric
XX
X
Numeric Alpha
Type of
Instruction
System Instruction No
System Designation
Rating of Main Equipment
Type of Manual
Product Code
1.1 PRODUCT CODE
B
Boiler
BA
Boiler Aux.
T
Turbine
TA
Turbine Aux.
G
Generator
GA
Generator Aux
P
Power Plant Piping
CI
C&I
1.2 TYPE OF MANUAL
1
Erection
2
Commissioning
3
Service
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 5

6. 1.3 RATING OF MAIN EQUIPMENT
01
200/210 MW
02
120 MW
03
110 MW
04
60 MW
05
30 MW
06
100 MW
07
235 MW
08
500 MW
KWU Design
09
210 MW
KWU Design
10
120 MW
KWU Design
11
60 MW
KWU Design
12
70 MW
KWU Design
13
Industrial Units
14
210 MW
Tower Type Concrete Pylem
15
210 MW
Tower Type Steel Structure
16
500 MW
Tower Type Once through
17
250 MW
18
CCP
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 6

7. 1.4 SYSTEM DESIGNATION
SNO
DESCRIPTION
1.
TECHNICAL DATA
2.
INSTRUCTION FOR HANDLING AND STORAGE
OF TURBINE
3.
ERECTION SEQUENCE
4.
ERECTION PROCEDURE
5.
GROUTING PROCEDURE
6.
ASSEMBLY OF IP MODULE AT SITE
7.
SEALING AND ANTISEIZING COMPOUNDS
8.
CRITICAL ACTIVITIES
9.
SPRING LOADED FOUNDATION
10.
ERECTION OF PIPING
11.
SPECIFICATION FOR GAS HEATING DEVICE
12.
SPECIFICATION FOR BREECH NUT HEATING
DEVICE
13.
SPECIFICATION FOR THERMAL INSULATION
1.5 TYPE OF INSTRUCTION
G
General
T
Technical
L
Log Sheet
C
Check List
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 7

8. LOAD
500 MW
RATED
524.2
MAX. UNDER VALVE WIDE OPEN (VWO) CONDITION
CONSTRUCTION
500 MW
THREE CYLINDER REHEAT CONDENSING TURBINE
SINGLE FLOW HP TURBINE WITH 17 REACTION STAGES
TYPE
H30-100-2
DOUBLE FLOW IP TURBINE WITH 12 REACTION STAGES PER
FLOW
TYPE
M30-63
DOUBLE FLOW LP TURBINE WITH 6 REACTION STAGES PER
FLOW
TYPE
N30-2X10
2 MAIN STOP AND CONTROL VALVES
TYPE
EV320-1
2 REHEAT STOP AND CONTROL VALVES
TYPE
IV560
MAKE
DN-800
BHEL,TIRUCHY
1 SWING CHECK VALVE IN COLD REHEAT LINE
DN-320
2 BYPASS STOP AND CONTROL VALVES
EXTRACTION SWING CHECK VALVES :
EXTRACTION-1
EXTRACTION-2
: 1 SWING CHECK VALVE WITH ACTUATOR
EXTRACTION-3
: 1 SWING CHECK VALVE WITH ACTUATOR
&
1 SWING CHECK VALVE WITHOUT
ACTUATOR
EXTRACTION-4.1
: 2 SWING CHECK VALVE WITH ACTUATOR
EXTRACTION-4.2
: 2 SWING CHECK VALVE WITH ACTUATOR
EXTRACTION-5
: 1 SWING CHECK VALVE WITH ACTUATOR
&
-
: NO VALVE
MAKE
DN-800
BHEL,TIRUCHY
MAKE
DN-500
BHEL,TIRUCHY
MAKE
DN-500
BHEL,TIRUCHY
MAKE
DN-500
BHEL,TIRUCHY
MAKE
DN-400
BHEL,TIRUCHY
1 SWING CHECK VALVE WITHOUT ACTUATOR
EXTRACTION-6
: NO VALVE
SPEED
RATED SPEED
Bharat Heavy Electricals Limited
Rev 00, 7-98
50.0 /S
T1-08-0801G
Page No. 8

9. SPEED LIMITATION IN LOAD & STATION AUX. LOAD
OPERATION
MAX. SPEED, NO TIME LIMITATION
MIN. SPEED, NO TIME LIMITATION
:
:
524.2
51.5 /S
47.5 /S
PERMISSIBLE FOR A MAXIMUM OF 2 HRS. DURING THE LIFE OF
LP BLADING
SPEED
BELOW
SPEED
ABOVE
:
:
47.5 /S
51.5 TO 60 /S
SPEED EXECUTION RANGE AT OPERATION WITHOUT LOAD*
:
6.7 TO 47.5 /S
STANDARD OVER SPEED TRIP SETTING
:
MAX. 55.5 /s
* THIS SPEED RANGE SHOULD BE PASSED THROUGH IN ONE
SMOOTH OPERATION TO AVOID ENDANGERING THE
BLADES DUE TO RESONANCE
STEAM PRESSURES
RATED*
LONG TIME
OPERATION
SHORT TIME
OPERATION
INITIAL STEAM
166.7
166.7
20.7
BAR
BEFORE 1st HP DRUM STAGE
154.4
163.4
169.9
BAR
HP CYLINDER EXHAUST
44.9
52.0
57.4**
BAR
IP CYLINDER STOP VALVE INLET
40.3
46.7
55.2**
BAR
EXTRACTION 6
44.9
52.0
57.4
BAR
EXTRACTION 5
17.5
22.2
22.2
BAR
EXTRACTION 4
7.2
8.7
8.7
BAR
EXTRACTION 3
2.58
3.2
3.2
BAR
EXTRACTION 2
1.329
1.66
1.66
BAR
EXTRACTION 1
0.257
0.41
0.41
BAR
LP CYLINDER EXHAUST
0.1013
0.3
0.3
BAR
* THESE VALUES CORRESPOND TO 500 MW LOAD WITH 3% MAKE-UP AND 0.1013 BAR BACK
PRESSURE WITH ALL HEATERS IN SERVICE AND RATED STEAM CONDITIONS.
** THE SAFETY VALVES MUST BE SET SO THAT THESE SHORT TIME VALUES ARE NOT EXCEEDED.
LONG TIME OPERATION : UPPER LIMIT VALUE, PERMISSIBLE WITHOUT TIME LIMIT.
SHORT TIME OPERATION : PERMISSIBLE MOMENTARY VALUE. THE AGGREGATE DURATION OF
SUCH SWINGS MUST NOT EXCEED 12 HOURS IN ANY ONE YEAR.
ALL PRESSURES ARE ABSOLUTE PRESSURES
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 9

10. LOW VACUUM TRIP, STANDARD SETTING
HYDRAULIC LOW VACUUM TRIP
:
0.3
BAR
ELECTRICAL LOW VACUUM TRIP
:
0.3
BAR
HYDRAULIC LOW VACUUM TRIP BYPASS OPERATION
:
0.6
BAR
:
35
MBAR
SEAL STEAM SUPPLY SYSTEM
PRESSURE IN SEAL STEAM HEADER (ABOVE ATMOSPHERIC)
AXIAL SHIFT
ALARM
TRIP
* 0.5 mm
* 1 mm
* DIRECTION OF ROTATION
ANTI CLOCK WISE WHEN VIEWED FROM FRONT PEDESTAL TOWARDS THE
GENERATOR
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 10

11. STEAM TEMPERATURES
RATED
VAL.
ANNUAL
MEAN
VALUE
LONG TIME
VALUE
(WITHIN
ANNUAL
MEAN
VAL.)
400 h
PER
ANNUM
80 h PER
ANNUM
MAX. 15
MIN IN
INDIVIDUA
L CASE
INITIAL STEAM
536.0
546.O
552.O
566.0
O
IP CYLINDER STOP VALVE INLET
536.0
546.3
552.0
566.0
O
RATED
VALVE *
LONG
TIME
OPERATI
ON
80 h PER
ANNUM
MAX. 15
MIN IN
INDIVIDU
AL CASE
IN
SPECIAL
CASES
AT NO
LOAD
HP CYLINDER EXHAUST
340.0
360.0
440.0
500.0**
O
EXTRACTION 6
340.0
360.0
440.0
500.0**
O
EXTRACTION 5
413.9
421.9
459.9
O
EXTRACTION 4
292.1
304.1
346.4
O
EXTRACTION 3
187.3
195.3
242.3
O
EXTRACTION 2
128.3
139.3
184.3
O
EXTRACTION 1
66.5
86.5
136.5
O
LP CYLINDER EXHAUST
46.1
70.0
70.0
O
C
C
C
C
C
C
C
C
C
C
LONG TIME OPERATION : UPPER LIMIT VALUE, PERMISSIBLE WITHOUT TIME
LIMIT.
*
THESE VALUES CORRESPOND TO 500 MW LOAD WITH 3% MAKE-UP AND 0.1013 BAR
BACK PRESSURE WITH ALL HEATERS IN SERVICE AND RATED STEAM
CONDITIONS.
**
ONLY VALID FOR THE NO LOAD PERIOD WITH HIGH REHEAT PRESSURE AFTER
TRIP-OUT FROM FULL LOAD OPERATION. FOR INDIVIDUAL CASE APPROX. 15
MINUTES
THE TURBINE IS IMMEDIATELY RE-LOADED OR THE BOILER IMMEDIATELY
REDUCED TO MINIMUM LOAD IF NO LOAD OPERATION IS MAINTAINED.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 11

12. CASING TEMPERATURES
ALARM
AT
MACHINE MUST BE
SHUT DOWN AT
HP TURBINE CASING EXHAUST
480
500
O
OUTER CASING OF LP CYLINDER
90
110
O
WALL TEMPERATURES
C
C
PERMISSIBLE DIFFERENTIAL TEMP. BETWEEN PARALLEL STEAM SUPPLY LINES :
O
•
NO TIME LIMITATION
•
SHORT TIME PERIOD (15 MIN.) : 28 C
: 17 C
O
IN THE HOTTEST LINE THE LIMITATIONS INDICATED FOR INITIAL STEAM & REHEAT TEMP. MUST NOT BE EXCEEDED.
O
SPRAY WATER TO LP TURBINE MUST BE SWITCHED ON AT 90 C.
ALARM
AT
MACHINE MUST BE
SHUT DOWN AT
DIFFERENCE BETWEEN UPPER & LOWER
CASING HALVES HP TURBINE. MIDDLE
* 90
* 100
O
LP TURBINE. FRONT
* 30
* 45
O
LP TURBINE. REAR
* 30
* 45
O
TEMPERATURES DIFFERENCE
C
C
C
FEEDWATER HEATER OUT OF SERVICE
OPERATION WITH FEEDWATER HEATER OUT OF SERVICE
MAIN STEAM
FLOW Kg/s
LOAD
MW
EXTRACTION A6 = 0
395
500
EXTRACTION A5 = 0
421
500
EXTRACTION A3 = 0
423
500
EXTRACTION A2 = 0
425
500
EXTRACTION A1 = 0
423
500
EXTRACTION A6, A5 = 0
400
525
OUTPUT LIMIT DURING TESTING WITH AUTOMATIC TURBINE TESTER
TESTING OF MAIN STEAM STOP & CONTROL VALVE
400
MW
TESTING OF HRH STEAM STOP & CONTROL VALVE
200 - 500
MW
MOTORING :
MOTORING IS THE CONDITION IN WHICH THE TURBINE IS DRIVEN BY THE GENERATOR AT
RATED SPEED WITH THE STOP & CONTROL VALVES CLOSED. IN THIS OPERATING MODE,
CERTAIN TURBINE COMPONENTS ARE HEATED UP BY WINDAGE POWER IN THE BLADING.
TO PREVENT HEAT-UP BEYOND PERMISSIBLE TEMPERATURES, MOTORING MUST NOT BE
ALLOWED TO CONTINUE FOR LONGER THAN ONE MINUTE. IF THE CONDENSER LOW
VACUUM LIMIT OF 0.3 BAR IS EXCEEDED, MOTORING MUST NOT BE ALLOWED TO CONTINUE
FOR MORE THAN 4 SECONDS.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 12

13. BEARING TEMPERATURES
ALARM
AT
MACHINE MUST BE
SHUT DOWN AT
OPERATION TEMPERATURE BELOW 75 OC
90
120
O
OPERATION TEMPERATURE 75 TO 85 OC
100
120
O
OPERATION TEMPERATURE 85 TO 90OC
110
120
O
OPERATION TEMPERATURE ABOVE 90OC
115
120
O
C
C
C
C
VIBRATION
ABSOLUTE BEARING
HOUSING VIBRATION
ABSOLUTE SHAFT
VIBRATION
30 µ m ABOVE
NORMAL LEVEL*
STANDARD ALARM SETTING
µm
MAXIMUM ALARM SETTING
35
120
µm
LIMIT VALUE FOR TRIPPING
45
200
µm
* THE NORMAL LEVEL IS REPRODUCIBLE VIBRATIONAL BEHAVIOUR TYPICAL FOR THE MACHINE AND
DEPENDENT ON THE OPERATING CONDITIONS, VIBRATION READINGS INDICATED IN CONTROL
ROOM ARE HALF PEAK. THE ABOVE VALUES ARE ALSO GIVEN IN HALF PEAK.
WEIGHTS
HP TURBINE, COMPLETELY ASSEMBLED
:
94.6
T
IP TURBINE. TOP HALF OUTER CASING
:
25.7
T
IP TURBINE, TOP HALF INNER CASING, COMPLETE WITH BLADING
:
15.5
T
LP TURBINE. TOP HALF OUTER CASING COMPLETE
:
42.6
T
LP CYLINDER, TOP HALF OUTER SHELL OF INNER CASING, COMPLETE
WITH BLADING, STATIONARY BLADE CARRIERS & DIFFUSER
:
38.5
T
HP TURBINE ROTOR, COMPLETE WITH BLADING
:
16.3
T
IP TURBINE ROTOR, COMPLETE WITH BLADING
:
23.1
T
LP TURBINE ROTOR, COMPLETE WITH BLADING
:
85.8
T
MAIN STOP & CONTROL VALVE, COMPLETE WITH SERVO MOTORS,
WITHOUT BEND & PIPE SECTION
:
20.9
T
REHEAT STOP & CONTROL VALVE, COMPLETE WITH SERVO
MOTORS, WITHOUT BEND & PIPE SECTION
:
32.2
T
ALL WEIGHTS HAVE BEEN CALCULATED WITH SAFETY ALLOWANCES. SLINGS
CHOSEN MUST PROVIDE SUFFICIENT SECURITY.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 13

14. OIL SUPPLY
MAIN OIL TANK, RATED CAPACITY
:
25/40
Cu . M
Ist OIL FILLING (ESTIMATED)
:
47.5
Cu . M
FLUSHING OIL QUANTITY (ESTIMATED)
:
28.5
Cu . M
OIL COOLER FOR OPERATION, NUMBER
:
1
NO.
OIL COOLER FOR RESERVE, NUMBER
:
I
NO.
OIL TEMP. AT COOLER OUTLET, UNIT IN OPERATION
MIN.
NORMAL
MAX.
:
:
:
38
45
47
MAX.
:
75
O
NORMAL
MAX.
:
:
20
25
O
OIL TEMP. AT COOLER OUTLET, UNIT SHUT DOWN
TEMP. RISE OF OIL IN BEARINGS
O
C
C
C
ESTIMATED OIL REQUIREMENTS OF BEARINGS :
BEARING 1(HP TURBINE, FRONT PEDESTAL)
:
0.8
dm3/S
BEARING 2
:
15.4
dm3/S
BEARING 3
:
4.1
dm3/S
BEARING 4
:
8.6
dm3/S
GENERATOR FRONT BEARING
:
7.92
dm3/S
GENERATOR REAR BEARING
:
7.92
dm3/S
EXCITER BEARING
:
0.70
dm3/S
1 DUPLEX OIL FILTER FOR BEARING OIL (FULL FLOW)
:
200
mm
DUPLEX OIL FILTER . TYPE - 2.62.9. SIZE 355/750. MAKE
:
BOLL & KIRCH
FILTRATION PARTICLE SIZE OF DUPLEX FILTER ELEMENT
:
37
µm
FILTRATION PARTICLE SIZE OF MAIN OIL TANK FILTER
ELEMENT
:
250
µm
SAFETY VALVE IN JACKING OIL SYSTEM, SETTING
MAX.
:
200
BAR
PRESSURE LIMITING VALVE IN JACKING OIL SYSTEM,
SETTING
:
100
BAR
1 DUPLEX OIL FILTER FOR JACKING OIL
:
25
mm
FILTRATION PARTICLE SIZE OF JACKING OIL FILTER
:
37
µm
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 14

15. OIL PUMPS
JACKING
OIL PUMP
MAIN OIL
PUMP
AUXILIARY
OIL PUMP
DC
EMERGENCY
OIL PUMP
1
2
1
BHEL
KSB
KSB
TUSHAKO
97.22 dm3/S
ETA-15050VVL
ETA-10033VVL
SDF80
CAPACITY
(RATED)
75
89.25
30
1.53
dm3/s
DISCHARGE
PRESSURE
(GAUGE)
8.6
6.2
2.3
178
BAR
SPEED
50
24.75
24.3
49.42
/s
DRIVE
TURBINE
AC MOTOR
DC MOTOR
QUANTITY
MAKER
TYPE
Bharat Heavy Electricals Limited
Rev 00, 7-98
AC : 2
DC : 1
AC
MOTOR
DC
MOTOR
T1-08-0801G
Page No. 15

16. CONTROL FLUID SUPPLY
CONTROL FLUID TANK, RATED CAPACITY
:
10/16
Cu . M
Ist FLUID FILLING (ESTIMATED)
:
15
Cu . M
FLUSHING FLUID QUANTITY (ESTIMATED)
:
10
Cu . M
CONTROL FLUID COOLER FOR OPERATION, NUMBER
:
1
NO.
CONTROL FLUID COOLER FOR RESERVE, NUMBER
:
I
NO.
CONTROL FLUID MAINTENANCE EQUIPMENT :
GEAR PUMP
MANUFACTURER
TYPE
:
:
STEIMEL
BGK 2-24R
FLUID FLOW
:
0.28
dm3/S
GAUGE PRESSURE
:
3.06
at
SPEED
:
25
S-1
MOTOR POWER
:
0.75
KW
2 EARTH FILTERS
MANUFACTURER
TYPE
:
:
:
EARTH FILLING MESH
1 FINE MESH FILTER
MANUFACTURER
TYPE
:
:
FILTRATION PARTICLE SIZE
:
FILTER MATERIAL
:
ROTRING
PYG5-350
140
Kg
ROTRING
S-1800-14-TUY
µm
3-5
COTTON
CONTROL FLUID SUPPLY SYSTEM
A FIRE RESISTANT FLUID IS USED FOR THE CONTROL SYSTEM
SCOPE
The document covers all steam turbine components and provides the handling,
inspection and storage instructions for large steam turbine components at site.
A strict adherence to these instructions is necessary to avoid damages during
handling and storage at site.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 16

17. HANDLING OF EQUIPMENT :
In any kind of rigging work it is necessary to strictly observe the safety precautions,
since even the slightest negligence and non observance of the rules may result
in accidents, which may cause damage to equipment or injury to men.
The site for the rigging work involving lifting and conveying of loads should be well
lighted. The loads must not be lifted unless the crane operator can see clearly
the signals given by the rigger.
The positions where the slings are to be put, are marked on the packages and on
the drawings. While lifting/handling these packages/equipment, the slings
should only be put at the proper places.
The slings of the proper sizes and lengths should only be used for handling the
equipment/packages. The angle between the two arms of the sling at the
crane hook should be small (depending upon the dia of the sling) so as to have
proper loading of the sling.
The turbine rotors and cylinder covers (in assembled condition are lifted by the
use of special lifting devices supplied by BHEL. The use of these lifting
devices facilitates correct slinging and maintain horizontal position of the
components. These devices, after use, should be properly stored and
conserved so as to ensure that they do not get damaged during storage.
Before using them, they should be thoroughly inspected.
The work related to handling of the loads (packages or equipment) by crane or by
other hoisting mechanism should be entrusted to trained riggers only. If
the rigger/operator is not sure of the weight of the item/package (load) to
be handled, he must ask for the required information before handling the
equipment.
The rigger and the crane operator should see that the hook and the ropes of the
crane occupy vertical position, before hoisting the load. Dragging of the load
by slanting ropes is not allowed. The center of gravity of the load should be
aligned with the vertical axis of the crane hook.
The eye bolts, 'D' shackles, turn buckles, and wire ropes of suitable sizes should
only be used for handling of the equipment. Before using, they should be
thoroughly inspected to their full threads, so as to avoid any chance of
slipping then the load comes on them.
Before giving a signal to lift the load, the rigger must check and ensure that there are
no loose parts or tools on the load, which might fall during lifting. Then the load
must be lifted 100 or 200 mm high for checking the uniformity
of sling
tensioning and reliability of lashing. If it is necessary to rearrange the sling
lengths, the load must be lowered and then the slings rearranged.
Before horizontal conveyance of the load the rigger must see that the load has been
lifted to a height at least 0.5 M above the tallest object, on the path of the load.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 17

18. While the load is being conveyed, the rigger must accompany it and see
that it is not moved above any person. Prior to lowering the load the rigger
should examine the ground on which the load will be, lowered and make sure
that these is no risk of falling or slipping of the load.
If any one of the personnel present during lifting or lowering of the load detects some
defect of the crane or sling of notices some conditions jeopardizing the lifting or
lowering operation, he must give a signal for emergency grounding of the
package or components.
Smooth lifting and transportation of equipment must be ensured. Shocks and jerks
should be avoided.
All
lifting devices, slings must be
inspected and tested.
properly
conserved after
use and periodically
In the turbines having diaphragms, it is prohibited to handle diaphragms by putting
slings in between the blades. For handling the welded diaphragms, special
lifting devices is supplied by BHEL and the cast diaphragms are handled
by putting the eye bolts, for which the provision of threads holes have been
made in the diaphragms.
While handling the bearings, it is prohibited to put the sling across the rabbit surface of
the bearings. Threaded holes have been provided; in which the eye bolts have
to be put for handling of the bearings.
While handling the cylinders, it must be ensured that the slings or any other material
does not get rubbed at their horizontal and vertical parting planes or at any
other machined surface.
The handling of the long components such as longitudinal girder, endwall etc. should
be done with extra care. When they are placed on the floor, in addition to the
end supports, few extra supports at the intermediate positions must be provided.
While handling LP rotor with free standing blades, care must be taken to ensure that no
force is exerted on the free standing blades to avoid collapsing of clamping
pieces under blade root.
MARKINGS ON PACKING CASES
Various symbols are marked on the packing cases as per 0456.001 to facilitate
storage and handling of the crates and protection of equipment inside.
INSPECTION
Before storing the equipment it should be opened for visual examination or the
internal packing, protective coating and condition of the equipment. Any
damage to packing and conservation should be immediately rectified.
It
is necessary to carryout first inspection within three weeks of arrival of the
consignment. Thereafter, all the equipment should be inspected once in every
three months to insure that the conservation is intact. During rainy season, the
inspection should be done once in a month. At any time, if any original
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 18

19. conservation is found damaged, it should be reconserved as per
conservation instructions No. ST 33004.
relevant
While inspecting the packages containing rotors, special care should be taken to check
the journals. In case of slightest sign of pitting on the journals and thrust
collar, immediate steps for rectification should be taken and equipment
reconserved as per relevant conservation instructions.
STORAGE
All steam turbine equipment should be accommodated in the designated place of
storage immediately after arrival at destination. This is very essential particularly
during the rainy season.
Store houses fall into the following categories
TYPE OF
STORE
HOUSE
CONDITIONS
TEMP.
RELATIVE
HUMIDITY
'P'
+50 C
to
500 C
< 70 %
'Q'
upto
500 C
-
Roofed area with walls (of brick /
asbestos/ GI sheet ) around and
cemented / pucca hard floor.
'R'
-
-
Raised platform with shed of asbestos /
GI sheet / water proof tarapaulin.
'S'
-
-
Raised Platform.
Bharat Heavy Electricals Limited
Rev 00, 7-98
ARRANGEMENT
Totally enclosed, rain proof, ventilated
and dry with cemented floor.
T1-08-0801G
Page No. 19

20. The
platforms and store-houses should be built up in conformity with the fire
prevention rules and standards. Complete storage area especially the ‘R’ & ‘S’
catagory must be adequately fenced & protected against theft & pilferage.
These store houses and areas around them should have proper drainage facility for
the sub-soil, surface and rain water. The water should not be allowed to stand
or get accumulated in these areas, especially where the material has been
stored.
Store house should be provided with proper ventilation facilities.
Level should be maintained for all the packages and equipment and should be
uniformly supported to avoid distortion. The long packages should be
supported at intermediate places also, so as to avoid sagging during storage.
Store houses should preferably be equipped with proper lifting devices to ensure
normal handling of equipment.
Small and medium size parts can be kept on shelves with proper identification tags.
Packages upto 5 tones can be placed on upon the other upto 2.5m in height using
required number of wooden spacers 50 mm thick. In doing so, lighter
packages would be laid upon heavier once to avoid any damage to lower
packages.
Articles weighing more than 5 tones should be laid in a single tier.
For heavier components under ‘Q’, the roof/walls may be constructed/fabricated after
placement of the component on cemented/pucca hard floor.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 20

21. STORAGE OF STEAM TURBINE COMPONENTS
SNO.
DESCRIPTION OF THE COMPONENT
TYPE OF
STORAGE
1.
FOUNDATION BOLT
Q
2.
EMBEDDED PARTS (ADDITIONAL)
R
3.
COMPONENTS OF BASE PLATE ASSLY.
Q
4.
BASE PLATE LP CASING
R
5.
LP OUTER CASIONG
R
6.
LONGITUDINAL GIRDER (LEFT & RIGHT)
R
7.
LP FRONT WALL (TS&GS)
R
8.
LP SHAFT SEALING (FRONT & REAR)
Q
9.
AUXILIARIES OF TURBINE
Q
10.
HP/IP BEARING PEDESTAL
Q
11.
HP/IP BEARING PEDESTAL ASSEMBLY PARTS
Q
12.
IP/LP PEDESTAL ASSEMBLY
Q
13.
LP/GEN. PEDESTAL
Q
14.
BEARING PEDESTAL PARTS
Q
15.
FRONT BEARING PEDESTAL
Q
16.
LIFTING BEAM
R
17.
LP CASING EXTRACTION A1
R
18.
LP EXTRACTION A2
R
19.
LP EXTRACTION A3
R
20.
LP EXTRACTION PIPE SHEATHING
R
21.
INNER GUIDE PLATE DIFFUSER
R
22.
DIFFUSER (UPPER & LOWER HALVES)
R
23.
LP INNER-OUTER CASING (VH)
Q
24.
LP INNER CASING ASSEMBLY (LH & VH)
Q
25.
HEATING DEVICE
Q
26.
LP CASING ASSEMBLY
Q
27.
LP INNER CASING ASSEMBLY (FASTENER)
Q
28.
INNER GUIDE PLATE DIFFUSER (GS)
R
29.
LP ROTOR
Q
30.
IP TURBINE
Q
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 21

22. 31.
IP TURBINE PARTS
Q
32.
IP INLET PIPES
Q
33.
HP TURBINE
Q
34.
HP INLET ASSEMBLY
Q
35.
HP EXHAUST ELBOW
Q
36.
HPT RELATED PARTS
Q
37.
FRAME FOR SUSPENSION (ESV)
R
38.
SUSPENSION OF VALVE (ESV)
Q
39.
ESV & CV CASING WITH VALVE
Q
40.
ESV SERVOMOTORS WITH LIMIT SWITCH
Q
41.
HP CONTROL VALVE SERVOMOTORS
Q
42.
SUSPENSION OF VALVE (IV)
Q
43.
IV & CV CASING WITH VALVE
Q
44.
IV SERVOMOTORS WITH LIMIT SWITCH
Q
45.
IP CONTROL VALVE SERVOMOTORS
Q
46.
FRAME FOR SUSPENSION (IV)
R
47.
IV SERVOMOTORS WITH LIMIT SWITCH
Q
48.
STEAM BLOWING & HYD. TEST DEVICE
Q
49.
TOOLS FOR GOVERNING SYSTEM
Q
50.
SUSPENSION OF LPB VALVE
Q
51.
WATER INJECTION VALVES
Q
52.
CHEST LPB WITH STOP & CONTROL VALVE
q
53.
LPB STOP VALVE SERVOMOTOR
Q
54.
LPB CONTROL VALVES SERVOMOTORS
Q
55.
INJR. FOR SUCTION PIPE NB 350
R
56.
INJR. FOR SUCTION PIPE NB 300
R
57.
MAIN OIL TANK
R
58.
MAIN OIL TANK & NOZZLE ASSEMBLY
R
59.
OIL STRAINER
Q
60.
LEVEL MONITOR INSTALLATION
Q
61.
INSTRUMENTS
Q
62.
LEAKAGE / DIRTY FLUID TANK
R
63.
VARIABLE ORIFICES & THROTTLE
Q
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 22

23. 64.
CONTROL FLUID TANK
R
65.
CONTROL FLUID TANK NOZZLE ARRANGEMENT
R
66.
EXPANSION TANK
R
67.
FILTER & PR. DAMPING DEVICES
Q
68.
CROSS AROUND PIPE
R
69.
SUPPORT FOR CAP
R
70.
CHANGE OVER VALVE
R
71.
RATING & MONOGRAM PLATES
Q
72.
OIL STRIPER
R
73.
HOUSING FOR HRH STEAM STRAINER
R
74.
HOUSING FOR MAIN STEAM STRAINER
R
75.
MS & HRH STR.HSG GASKET
Q
76.
STEAM STRAINER MS
Q
77.
STEAM STRAINER HRH
Q
78.
COMPENSATOR
Q
79.
TURBINE CONTROL LPB / SUPPLY RACK
Q
80.
TEMPERATURE & PRESSURE CONNECTIONS
Q
81.
PR. TRANSMITTERS BAR. PROBES THERMOCOUPLES
Q
82.
TRANSMITTERS & JUNCTION BOXES
Q
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 23

24. STORAGE & PRESERVATION OF COMPONENTS OF
TURBOGENERATOR, EXCITER AND SYSTEMS
SNO.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
DESCRIPTION OF THE COMPONENT
EMBEDDED PARTS
FOUNDATION PARTS
WOUND STATOR WITH GAS COOLERS
TURNION FOOT PLATES
ROTOR
ASSEMBLY OF PIPE CONTROL FOR GAS COOLERS
END SHIELDS
FAN SHIELD, GEN VVIEW HEADER ASSEMBLY
TERMINAL BUSHING AND HEADER ASSEMBLY
BEARING WITH BRUSH GEAR
SEAL BODY
TEMP. CONNECTION
CASING FOR TURNIONS
ERECTION MATERIALS
ERECTION DEVICES
SHAFT SEALS
SEAL RINGS
ADOPTING RING
AUXILIARY BEARING
CENTRIFUGAL FAN
CARBON DIOXIDE VAPOURISER
FILTER O.C.P.
EXPANSION TANK
OIL SEPARATOR
PRE CHAMBER
S.O.S.T.
SEAL OIL UNIT
HYDROGEN DISTRIBUTION
CARBON DIOXIDE DISTRIBUTION
VALVES FOR AUXILIARY SYSTEMS
GAS UNITS
FLEXIBLE LEADS
TYPE OF
STORAGE
R
R
Q
Q
Q
R
Q
R
Q
Q
Q
Q
R
Q
R
Q
Q
Q
Q
Q
Q
Q
R
R
R
R
Q
R
R
P
Q
Q
STORAGE & PRESERVATION OF COMPONENTS OF
HEAT EXCHANGERS
SNO.
DESCRIPTION OF THE COMPONENT
TYPE OF
STORAGE
PRODUCT : CONDENSER
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 24

25. 1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
BOTTOM PLATE
LOWER DOM WALL
SIDE WALL
WATER CHAMBER
UPPER DOM WALL
STIFFENING PIPES
STIFFENING RODS
TUBE SUPPORT PLATE
WATER BOX
AIR EXTRACTION PIPING
HOTWELL
SPRING ELEMENTS
LOOSE ITEMS
INSTRUMENTS
CONDENSER TUBES (STAINLESS STEEL)
CONDENSER TUBES (NON-FERROUS)
VACUUM PUMP
EJECTOR
AIR MEASURING DEVICE
S
S
S
Q
S
S
S
R
R
R
S
R
Q
Q
R
Q
Q
R
Q
PRODUCT : HEATER
1.
2.
3.
4.
5.
1.
2.
3.
4.
5.
6.
GLAND STEAM CONDENSER
STAND PIPE
INSTRUMENTS
DRAIN COOLER
L.P.HEATERS
PRODUCT : COOLER
OIL COOLER
CONTROL FLUID COOLER
STATOR WATER COOLER
HYDROGEN COOLER
EXCITER AIR COOLER
INSTRUMENTS / LOOSE ITEM
Bharat Heavy Electricals Limited
Rev 00, 7-98
R
Q
Q
R
R
R
R
R
Q
Q
Q
T1-08-0801G
Page No. 25

26. MAXIMUM PERMISSIBLE LOADING FOR WIRE ROPES IN KG.
NOMINAL
DIA (d) OF
ROPES mm
SINGLE
CORD
9
DOUBLE CORD WITH INCLUDED ANGLE OF
0o
45o
90o
120o
522
1044
965
738
522
12
1170
2340
2070
1580
1170
18
2150
4300
4000
3060
2150
24
3850
7700
2100
5400
3850
30
6200
12400
11500
8800
6200
36
9000
18000
16600
12700
9000
42
12200
24400
22600
17300
12200
48
16000
32000
29500
22600
16000
54
20200
40400
37300
28500
20200
60
24900
49800
46000
35200
24900
66
30100
60200
55700
42600
30100
72
35800
71600
66200
50700
35800
78
42100
84200
77700
59500
42100
84
48800
97600
90200
69000
48800
90
56000
112000
103500
79200
56000
96
63700
127400
117700
90000
63700
102
71900
143800
132900
101700
71900
108
81000
162000
149700
114500
81000
114
89900
179800
166100
127100
89900
120
99700
199400
184300
141100
99700
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 26

27. ERECTION SEQUENCE
(For 500 MW Fixed pedestal type Turbine with spring loaded foundation)
1. Cleaning and checking of Turbine and Generator foundations as per the transverse
and longitudinal axis including their elevation.
2. Prepare and install LP base plates, HP front pedestal, HP rear pedestal, LP front
pedestal, LP rear pedestal along with their anchor bolts and anchor plates.
3. Provisionally
align and level all the pedestal and LP base
plates as per the
transverse and longitudinal axis including their elevation.
4. Matching of anchor plates of pedestal and LP base plates to ensure their perfect
seating.
5. Finally align and level HP front, HP rear, LP front and LP rear pedestals along with
LP base plates as per the transverse and longitudinal axis including their elevation
and catenary as per the design.
6. Prepare and install steel bars for LP casing centralising keys in foundation slab as
per the required center line .
7. Weld locating ring of LP front pedestal and steel bars of LP front and LP rear
centralising keys.
8. Prepare shuttering and grouting of the pedestals and LP base plates including
anchor plates of HP rear pedestal.
9. Prepare, install, align/ level both the LP girder along with their carrier plates.
10. Prepare , install and assemble LP front and rear end walls with the LP girders.
11. Level / align LP outer casing lower half as per the transverse and longitudinal axis
of the machine.
12. Install permanent packers of LP outer casing including their radial and axial keys.
13. Prepare and install LP inner outer casing along with gusset plates in position
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 27

28. 14. Align LP inner outer casing lower half and level it. Install LP casing parting plane
platform .
15. Prepare and install LP front and LP rear lower half shaft seals housing and align it
provisionally.
16. Prepare and install LP rotor along with their bellows in position.
17. Align LP rotor radially and axially in position and record free run out of rotor.
18. Record/ Ensure radial and axial clearances of the LP casing including rotor float
including fitting of final axial keys of the LP inner casing .
19. Box up LP inner inner casing and heat tighten the parting plane bolts.
20. Box up LP inner outer casing .
21. Prepare and place HP module in position on temporary packers.
22. Transfer the load of HP rotor on bearings from the transport device and align it
radially and axially.
23. Check free run out of HP rotor on journal and coupling face including its float.
24. Prepare and place IP module in position on temporary packers. (In case IP module
is sent to site in disassembled condition, refer Instruction T1-08-0606G.
25. Loading of IP rear end of the shaft on bearing and removal of transport device.
26. Provisionally align HP , IP and LP rotor .
27. Couple HP / IP rotor on temporary Bolts and align rotor / casing radially and axially.
28. Record/ Ensure IP rotor float by shifting HP casing axially.
29. Conduct Horn drop test of HP casing without any radial and axial keys and pipe
lines.
30. Conduct Horn drop test of IP casing without IP inlet upper half pipe lines.
31. Assembly of breech nut of HP casing and Main Steam Stop & Control valve
assembly.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 28

29. 32. Erection of Reheat Stop & Control valve assembly.
33. Weld IP inlet upper half pipe and record Horn drop values without radial-axial keys.
34. Alignment of HP/IP/LP rotors and their coupling on temporary bolts including its
couple runout.
35. Swing check of HP rotor on its front end with temporary alternate bolt tightened on
HP/IP coupling .
36. MOP alignment and its doweling.
37. Reaming/honing of HP/IP and LP/IP coupling including fitting of final coupling bolts.
38. Fixing of axial position of shaft and assembly of thrust bearing including its colour
matching.
39. Roll check of HP/IP casing and fixing of radial and axial keys of the casing (Casing
final packers need not to be put at this stage).
40. Assembly of bearings and checking of all clearances including fittings of side pads
of bearing, yoke keys etc.
41. Turbovisory works in all the pedestal i.e. assembly and calibration of thrust bearing
axial
shift, LP rotor expansions pick up, Hall generator and thermocouples of
bearing .
42. Preparations of the bearing for oil flushing.
43. Oil flushing of the machine and normalizing the bearing after oil flushing.
44. Preparation and floating of TG deck as per Instruction No. T1-08-0909G.
45. Decoupling of HP / IP, LP/IP, LP/Gen., Gen./Exciter coupling and rechecking of
alignment/catenary after floating of TG deck spring.
46. Final tightening of HP/IP, IP/LP , LP/Generator and Generator / Exciter coupling
after correcting the alignment including their couple run out and swing check of rotor
on HP Front and exciter rotor.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 29

30. 47. Checking /Correction of LP shaft seal clearance after floating of TG deck with CW
pump in operation and water in the hot well of condenser upto operating level.
48. Roll check of HP, IP casing in up and down direction only with TG deck in floating
condition and CW pump in operation including water in hot well upto normal level.
49. Assembly of final packers of the HP, IP casing after completing the roll check in up
and down direction.
50. Recording of final Horn drop of HP and IP casing after completing the welding of
HP inlet, HP exhaust , IP inlet and Cross around piping.
51. Preparation and boxing up of LP casing after competing the full Roll check of LP
casing and fitting of final casing packers and radial keys.
52. Barring gear.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 30

31. CHECKING OF FOUNDATION BEFORE CASTING
Customer to provide, center line and elevation point.
Check positioning of all the inserts and fixed points with respect to center line
in transverse and longitudinal direction as per BHEL Hardwar drawings.
Check elevation of all points.
Check verticality of all the pipe sleeves with the help of plumb.
Ensure proper locking of all the insert and fixed points before grouting.
Ensure leveling on the fixed points of LP girder and LP rear pedestal.
Preserve machined surfaces of all the fixed points against any damages due to
Improper handling.
Ensure proper flatness of the bottom seating plate of all the inserts.
Ensure proper stiffeners in all the vertical and horizontal embedment provided
for various purposes like hangers and supports etc.
Ensure proper cleaning of the area before casting.
Remove all unwanted material.
NOTE: In case of spring loaded TG deck refer Installation Instruction
No. T1-08-0909G prior to positioning of inserts etc.
CHECKS DURING CASTING/POURING OF CONCRETE
Casting of foundationTG deck should be carried out immediately after
inspection of the foundationTG deck i.e. within 3-4 days after final
inspection to avoid any disturbance to the inserts and fixed point.
Ensure no disturbance to the insert etc. during pouring of concrete while
vibrators are used.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 31

32. About 15-20 mm extra concrete may be left on top on all the pedestals and LP
base plate area for chipping/cleaning purpose at a later date.
Close all the pipe sleeve from top to avoid entry of concrete inside. Alternately
the pipe sleeve should be filled with sand.
CHECKING OF FOUNDATION AFTER CASTING
Clean complete foundation and remove all shuttering etc.
Ensure there is no loose concrete layer in the region where the pedestal and
base plates are to be laid. No repair should be done in this region without
consulting the turbine erection engineer.
Cover all the opening before checking any dimensional measurement to
avoid any accident.
Establish a suitable longitudinal axis considering the fixed point of the LP rear
pedestal and various pipe sleeves / inserts.
Establish a transverse axis as 90 degree with the help of the odolite.
Measure pitching/elevation of all the inserts and fixed points.
Measure elevation of all foundation on different pedestal and LP base plate area.
Check level of LP rear pedestal fixed points and if required correction may
be carried out.
PREPARATION OF FOUNDATION FOR PLACEMENT OF
PEDESTALS AND BASE PLATES:
Foundation are to be cleaned and loose concrete are to be chipped off.
Maintain elevation of foundation to ensure correct thickness of non-shrink
grout.
A reference point for elevation in respect of machine center line (equivalent to LP
rear pedestal) is to be maintained at a proper place. This point is to be
preserved with proper protection. For making reference point a one side
ground plate of about 200 x300 x20 mm may be used. This may be
welded on a I-beam near Generator. The ground position of the plate is
to be kept on top side and all elevation are to be transferred from this
point with the help of water level jar. A correct elevation reading is to
be punched on this plate. This reference point is to be used only during the
turbine erection period.
Clean and deburr piping sleeves of the foundation on ID/OD
of the pipe.
Ensure all corners of the foundation remains perfect during chipping of extra
concrete of foundation.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 32

33. PLACEMENT OF PEDESTALS
Open and clean the pedestal.
Ensure there is no paint/oil on bottom face of the pedestal sole plate.
Ensure there is no paint on inside surface or the pedestal and if required sand
blasting may be carried out at site.
Ensure correct fitting/clearance of locating rings of LP rear pedestal.
The half bore error of pedestals is punched by manufacturing unit however in
case it is not there, measure and punch half bore error of pedestal in
left/right side of the pedestal. If the error is nil then this may be
punched as zero-zero.
Ensure that the pedestal parting plane is feeler tight after tightening all the
parting plane bolts. If required, colour matching may be carried out but
scraping/cutting is to be done on upper half cover only.
Check proper colour contact of spherical/cylindrical supports of the bearing
with the pedestal.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 33

34. Check contact between spherical Torus piece of bearing and
spherical/cylindrical seat. In case of any variation in contact no
scraping/cutting to be carried out at site and this may be referred to
manufacturing unit. Also refer T1-08-0808G. Check centering of individual
bearing w.r.t. pedestal seal bores by fixing pianowire on individual
pedestal.
Ensure cleanliness of all pedestal oil lines. Close opening of oil lines of
pedestal to avoid any foreign material entering in these pipe lines during
erection at site.
Weld MOP suction and discharge pipe lines in HP front pedestal as per the
drawing before placement.
Assemble protection sheet in the foundation bolt holes of pedestals.
Assemble anchor bolts along with anchor plate of the pedestals. Ensure that
there is good contact available to the backing plate with the
foundation. If required colour matching/grinding may be carried out to
achieve the contact.
Assemble protection sheet in the anchor bolt hole from bottom side of HP rear
pedestal foundation to avoid entry of grout metal.
Ensure level of both anchor plate of H.P. rear pedestal with 70-90 mm gap for
filling of grouting concrete.
Adjust height of the Anchor Bolts as specified in the drawing.
PLACEMENT OF LP BASE PLATE, OVER THE FOUNDATION :
Clean all the four base plates.
Mark/punch center line on the base plate as per drawing.
Ensure proper cleaning of base plate on bottom side.
Put identification marks on each base plate to avoid any mistake in positioning of
the same.
Do colour matching of all the eight nos. carrier plate on both the faces.
Match LP base plate with the individual carrier plate.
Place all the four base plates in position along with their leveling screws and
foundation bolts.
Provisionally align and level all the four base plates.
Assemble protection sheet in the foundation bolt holes.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 34

35. ALIGNMENT OF PEDESTALS AND LP BASE PLATES
Provisionally align and level all the four pedestals including LP base plates with
reference to the earlier marked longitudinal and transverse axis. The
elevation reference is to be taken from the already positioned plate for
this purpose.
Align and level LP rear pedestal and set the elevation as per machine center line.
Use piano wire arrangement with micrometer for centering of pedestal bore and
use water level jar for setting of elevation. Use measuring tape to
maintain pitching of the bearing from one pedestal to another. Pedestals
are to be set in level condition on both longitudinal and transverse
direction. Align and level HP front, HP rear and LP front pedestals.
Elevation of the pedestals are to be set as per catenary of the machine
considering the half bore error of the pedestal if any.
Align and level, LP base plates. Elevation of LP base plate is to be kept higher
than the rear pair of LP base plate in line with catenary of rotor.
After alignment of LP rear pedestal weld the locating rings as mentioned in the
drawing.
During welding of locating ring, ensure that there is no movement in the
pedestal in any of the direction.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 35

36. GROUTING OF PEDESTALS AND LP BASE PLATES
Fill 3 to 8 mm washed Pea-gravel in all the anchor bolts sleeves. These gravel
are necessary to give damping effect to the anchor bolts during operation
of the machine.
Seal anchor bolts holes after filling of gravel to avoid any entry of grout metal.
Medical tape may be used for sealing of these anchor bolt holes.
Clean foundation with compressed air.
Make shuttering of all the pedestal and LP base plates. Use thick polythene
sheet inside the shuttering to give better finish and avoid moisture
absorption by shuttering.
Shuttering should be made with maximum care to avoid any leakage of grout
concrete. All sides of the shuttering are to be sealed either with some
sealing compound or with thick mixture of grout material to avoid leakage
of grout material.
Foundation are to be kept wet for about 6 hrs. before grouting.
Non shrinkage cement duly approved by BHEL is to be used for grouting of the
pedestals and base plate.
Use fresh stock of the grouting material only and check the strength of the
material before use.
During grouting, the mixture has to be poured from one end only and it has to
flow to opposite end to avoid any blockage of air pocket.
Water curing is to be carried out for about 10 days duration.
All anchor bolts are to be stretched minimum after 21 days of grouting.
HP, IP & LP module placement work can be taken up after 24 hours of grouting
of the pedestal and base plates.
For individual pedestal and base plate, grout mixture should be poured in one lot
only.
PLACEMENT OF HP MODULE IN POSITION
Ensure matching of all the four palms of the module where it is resting on the
pedestals.
Ensure matching and parallelity of front and rear key block of the HP casing.
Assemble all four jacking screw of HPC and ensure their free movement.
Clean journals and coupling of the HP rotor.
Record journal dia, coupling hole sizes and spigot dia of HP rotor.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 36

37. Lift module in level condition and place it in position by keeping it 3 to 5 mm
toward front pedestal side.
During placement of module use temporary packers similar to permanent and
additionally support it by four jacking screws.
Ensure load on all four packers with the help of some additional shims if
required.
Install temporary radial and axial keys of the casing.
Prepare HP rotor for alignment (Ref. section 20 before placing the IP module.
PLACEMENT OF IP MODULE IN POSITION
Ensure matching of all the four palms of the module where it is resting on the
pedestals.
Ensure matching and parallelity of front and rear key block of IP casing.
Assemble all four jacking screws of IP casing and ensure their free
movement. If these jacking screw holes are provided with the bolts
from factory then same are to be removed before placement of module.
Clean IP rotor on both sides including coupling and journal.
Record spigot /recess, journal dia, and coupling hole sizes.
Lift the module in level condition and place the module in position by moving
about 7 to 8 mm towards generator end. Use temporary packers for
placement of module in position and additionally support the module with
jacking screws.
Ensure load on all four packers with the help of some additional shims if
required.
Provisionally align the casing on front and rear pedestal bore. Install temporary
radial and axial keys of the casing with some shims.
Prepare IP rotor for alignment (Ref. section 20).
NOTE: In case IP module is sent to site in disassembled condition, refer
Instruction T1-08-0606G.
ASSEMBLY OF LP MODULE
This assembly can be divided in following sub assemblies:
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 37

38. Assembly of girder and end walls.
Assembly of LP inner inner and LP inner outer casing lower half.
Assembly / welding of LP outer casing.
Before starting assembly of LP casing in position, following works are
also to be completed :
- Positioning and welding of LP casing centering pin of front and rear
side.
- Positioning of key block of LP casing axial keys.
- Positioning of all internal of condenser.
POSITIONING AND WELDING OF LP CASING CENTERING
PIN
Two nos. centering pins are to be located below LP front and LP rear pedestal.
Necessary pipe along with two sq. end plates are already provided in the
foundation to take the radial load of the LP casing:
Plumb the center line from LP front and LP rear pedestal bore on both side
over the square plate of the foundation.
Establish accurate position of the pin and put a punch mark at a required height
and mark a circle and a controlling circle over all the four sq. Plates.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 38

39. Dia of the circle must be equal to pin dia. A template equivalent to pin dia has
to be made for this purpose with about 20 mm thick plate and a welded
pipe for using as an handle. The template dia must be very accurate and
same may be made on machine.
Make precise hole with gas cutting/grinding to match template on all four
embedded plate. Ensure that the template is fitted with minimum
clearance and hole center are perfect as per marking.
Drill hole of about 10 mm dia on one of square plate of LP front and on one
plate of LP rear for air venting to avoid cracks during welding.
Insert both the pins and carry out the welding as per laid down procedure.
Before welding set correct axial position of the pins.
Insert key block on both the pins and weld their locking ring also. Ensure
proper clearances in key block before welding of its locking ring.
Preheating of 200 degree Celsius or more to be achieved before any welding.
Dye penetrate test on root run and after final welding is to be carried out.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 39

40. ASSEMBLY OF GIRDER AND END WALL
Colour match side matching flange of girder with the surface plate.
Colour match seating flange of girder where it rests over the LP base plate.
Match and ensure parallality of axial key ways of girder.
Colour match side flanges of end wall.
Match and ensure parallality of key block of end wall.
Place left and right girder with carrier plate, spacer and lubrite packer on LP
base plate.
Provisionally align and level the girders. Set height of the girder equivalent to
machine center line maintaining catenary of the machine with the help of
water level jar arrangement.
Assemble locking plate of the front and rear end wall to facilitate its assembly
with the girders.
Assemble front and rear end wall with the girders and ensure perfect parting
plane level during tightening.
Align, level LP outer casing and ensure contact of packers by colour
matching/machining of spacer height.
Install LP casing radial and axial keys.
Assemble inner outer casing axial key blocks on left and right side of girder
and dowel them.
Lock with tack welding all the vertical joint bolts.
Put a seal weld run between girder and end wall joint all around except on top
face.
Weld girder and end wall parting plane joint with argon welding. Before
welding make a V groove with the help of a chisel and allow the projection
of material on surface. Do not make the groove by grinding.
Do colour matching with a surface plate on all four corner where argon welding
have been carried out.
ASSEMBLY OF LP INNER INNER AND LP INNER OUTER
CASING LOWER HALF
The LP inner inner casing lower half is received from factory in assembled
condition with LP inner outer casing lower half.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 40

41. Clean the casing and check all the threaded holes.
Do colour matching on all four corners of the casing where it rest over the
girder.
Colour match all eight carrier plates of inner casing on both side.
Assemble all carrier plates on girder and do the colour matching with
individual carrier plate.
Prepare Gusset plate of front and rear side with temporary radial keys for fitting
in LP inner casing.
Level and lift LP inner outer casing and assemble/weld both the gusset plates
with the help of some temporary support.
Lower the casing in position over the carrier plates fitted with spacer and lubrite
packer.
Provisionally align the casing radially and axially.
Support the gusset plate with the help of screw jack (about 10-15 tons) on front
and rear side by taking support from condenser stiffeners. Screw jack is to
be unscrewed after box-up.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 41

42. Adjust the height of the LP inner outer casing as per center line of the machine
and then level it with the help of water level jar arrangement.
Ensure that all the eight packers have good contact. Loading of each packer is
to be ensured.
Lower the casing by about 2 mm on all the eight packers with the help of shims
for placement of LP rotor to avoid any fauling during placement of rotor.
Fit and weld all gusset plate stiffener pipes except pipe between LP inner outer
casing and condenser. Do not make any weld connection between
condenser and any of these stiffeners till neck welding of the condenser
is over.
PLACEMENT OF LP ROTOR
Measure journal dia, spigot dia and coupling hole sizes.
Ensure centering of temporary bearing support in the LP front pedestal for
placement of LP rotor.
Place LP rear bearing in position.
Prepare shaft seal compensator along with gaskets (Gasket to be installed in
fully ring shape only ) and position them on LP rotor with the help of
supplied supports of compensator.
Lift LP rotor with the supplied lifting beam in perfectly level condition and place
it in position. During lowering of rotor ensure radial clearance with the
help of long feeler gauges in the LP casing.
WELDING OF LP OUTER CASING
The welding of LP outer cover is to be carried out before placement of LP
Rotor in position to avoid damage to the rotor.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 42

43. Colour match and remove all high spots of the matching flange of the LP
outer casing.
Ensure good contact between parted diffuser of LP front and LP rear cover.
Colour match and remove all the high spots of the parted diffuser/vertical face
to ensure good contact with the compensator at a later stage.
Colour match and remove all burrs and high spots from parting plane of LP outer
casing.
Side flange of LP front and rear cover are to be ensured in right angle to
achieve good contact with their matching flanges.
Place LP front LP rear cover along with parted diffuser and ensure feeler tight
joint after tightening the parting plane bolts. The joint must be feeler
tight just after normal tightening of bolts. Do not over tighten parting
plane bolts.
Ensure matching of parted diffuser face on both side of LP casing. If necessary
colour matching may be carried out to achieve a feeler tight joint.
Drill/ream all the parting plane holes as per drawings and install all dowel pins.
After fixing of LP front and rear cover measure the dimension for
positioning of both the center flanges. The dimension are to be recorded
in such a way that there is no clearance after fitting of center flanges in
position on both side with the LP front and rear cover. The center
flanges are supplied in extra length on both sides from the factory and
final length are to be maintained at site only.
Drill/ream dowel pin holes in center flanges and install all dowel pins in position.
Ensure drilling and reaming of all dowel pin holes to equal depth.
Fit both the center pieces of the cover in position.
Achieve the fitting clearances for welding as per laid down procedure.
Weld/lock LP upper half flange with respect to lower half casing with the help
of metal cleats to minimise the distortion during welding of LP cover.
The cleats may be welded at an interval of about one meter distance.
Carry out the welding as per the following welding procedure.
WELDING PROCEDURE
Tack weld the crowned seam joint. permanently welding approx. 100 mm at the
generator end of the joint.
Opposite tack welded radial joint 2, permanently weld approx. 100 mm of the
crowned seam joint, pos. 1, staggering the two weld ends to ensure a
perfect transition when the crowned seam joint is finish welded.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 43

44. Tack weld the crowned seam joint at regular intervals with a tack of 5T and pitch
of 25T.
When welding radial joint 2, shell plates 1 & 2, tacked together, rest on but are
not tacked to the retaining strip in the region of joint 1, so that any
shrinkage occurring during welding of seam 2 is not obstructed.
The tacking & welding sequence applies for all shells courses.
Weld radial seam at TE according to welding sequence plan.
Align, adjust and tack weld radial seam at GE.
Weld radial seam at GE according to welding sequence plan.
Weld crowned seam joint.
Align shell courses on joint strips and tack weld,
Weld on joint strips from center & ends of shell plate.
Insert pins in top half casing, release top half casing and lift to insert and tack
filler piece between joint strips.
Unbolt top half casing and lift in order to weld and finish - machine filler pieces in
the region of the joint surface.
Check welds according to specifications.
ALIGNMENT AND COUPLING OF LP-IP & HP ROTOR
LP rotor is to be aligned on pedestal seal bore and LP inner outer casing is to be
centralised in such a way that enough clearances are available to LP rotor,
during alignment. Now this alignment activity of all the three rotor can be
divided as below :
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 44

45. Preparation of HP rotor for alignment.
Preparation of IP rotor for alignment.
Preparation of LP rotor for alignment.
Alignment of LP-IP & HP rotors.
Reaming, honing of the coupling holes.
Balancing of coupling bolts weight.
PREPARATION OF HP ROTOR FOR ALIGNMENT
Align HP rotor with reference to front and rear pedestal seal bore reading. If
required move complete HP module along with the rotor.
Fix temporary radial and axial key of the casing on both front and rear side of
the casing. Remove HP front upper half transportation device.
Lift module by 0.20 mm on front side by putting additional shims in front
packers.
Insert HP front bearing in position.
Reduce 0.20 mm shims gradually and ensure about 0.10 mm load on the rotor. If
required further lower the front side of the module to achieve the loading
on bearing by about 0.10 mm.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 45

46. Remove HP front lower half transport device gradually and ensure no
movement between HP casing and rotor. If necessary adjust shims of
HP casing front packers.
During loading of bearing always ensure that the rotor is not fouling inside the
casing with the shaft seals. This may be ensured by checking with feeler
gauge also.
Check axial position of HP rotor in front side on left; right and top position
from the rotor reference point to the HPC as given in the shop protocol.
Insert and load the bearing in HP rear end in similar way as carried out in
case of HP front end and record axial position of rotor as per shop
protocol.
Lock axially HP rotor with some fixture along with the arrangement of
jacking screw for movement of rotor. This fixture may be mounted on rear
pedestal. Before locking of rotor ensure axial position of the shaft.
Center HP shaft with reference to HP casing front and rear spigot. If necessary,
move the casing readily to achieve the centering. A fixture can be
fabricated at site for mounting the dial gauge on both the end of the rotor
to check the centering of the shaft.
Use thick oil during rotation of shaft on the bearing.
Protect bearing from any of the dust particles. It is recommended to place
upper half of bearing in position to avoid dust and any other damage to
the shaft journal.
Realign the rotor shaft with respect to pedestal seal bore and if necessary
adjust the shims below spherical support of the bearing.
Care should be taken during alignment that radial and axial clearances
between rotor and casings does not get bridged.
Check HP rotor radial run out on journal and coupling.
Check axial run out on thrust collar and both the coupling faces of HP rotor.
Check axial float of the rotor. Compare values with shop protocol values. (Ref. T108-0802G). Deviations to be reported to Manufacturing Unit.
PREPARATION OF IP ROTOR FOR ALIGNMENT
The IP module is also to be prepared in line with the HP module. However
as IP rotor is provided with one side bearing and opposite side is coupled
with the HP rotor without a bearing, extra care is necessary during
alignment of rotor in IP casing. The additional point which are to be taken care
are explained below :
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 46

47. Place IP rotor rear end on bearing similar to the HP rotor and remove
transportation device.
Provisionally align HP/IP rotors and couple on temporary bolts by moving both
the modules. During coupling of the rotors, the transportation device of IP
front end is also to be taken out.
Check axial position of rotor w.r.t. IP casing and adjust as per shop protocol.
Check centering of IP rotor front and rear end w.r.t. IP casing (similar to the HP
rotor centering check).
Check float of the IP rotor. Compare values with the shop protocol values. (Ref.
T1-08-0802G). During checking of float ensure HP casing is not fouling
with HP rotor. If required HP casing may be moved axially for this purpose.
Check facial runout on IP rear coupling face and radial runout on journals and
couplings.
PREPARATION OF LP ROTOR FOR ALIGNMENT
Provisionally align LP rotor in pedestal seal bore placing the front end of shaft
on auxiliary bearing and rear end on bearing.
Align LP inner outer casing radially with the help of long feeler gauges and
install temporary radial keys in the gusset plate.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 47

48. Record all the radial and axial clearances of the LP casing without coupling
the LP-IP rotor. Variation if any in radial or axial clearances are to be
corrected/approved at this stage.
Remove shims from the front end of auxiliary bearing and keep rotor on lifting
tackle.
Record radial run out of LP rotor coupling and journal and axial run out of the
coupling faces of the both end.
Record float of the LP rotor by moving the LP inner outer casing lower half.
After ensuring the radial and axial run out of the LP rotor the LP inner outer
casing can be boxed up. Parting plane bolts of LP inner-inner casing are to
be heat tightened.
ALIGNMENT OF HP, IP AND LP ROTORS
Ensure radial and axial runout of all the three rotors are individually in order. If
necessary individual rotor module can be taken out for correction of
coupling face runout. Any variation on radial runout of rotor is to be
referred to the factory.
Match coupling faces of two rotor as per the axial face reading of the rotor.
Ensure that the higher point of the rotor coupling face and lower point of
another rotor coupling face are matched together. This is to be compared
with shop protocol also.
Preliminary align radially and axially all the three rotors and shift them in spigot
along with the casing to avoid fouling of rotor inside the casing.
During alignment achieve left and right movement of the rotor with the help of
shims in spherical / torus piece of the bearing. The up and down
movement of the rotor is to be achieved with the help of shims in the
cylindrical/spherical support of the bearing . The adjustment of shims in
the bearing should be within the permissible limits only.
Ensure during alignment that the catenary of the shaft is maintained.
Check/record spigot clearance of HP-IP and LP-IP rotors by actually moving them
in spigot.
Install four nos. supplied bolts along with one/two pins in HP-IP and LP-IP
coupling. Hand tighten the coupling bolts by keeping a gap of > 1.00 mm
in coupling faces for alignment.
Rotate the rotor system and record the coupling gap at 90 Deg. interval on
left, right and top position. Ensure that the coupling, bolts and pins
remain free while recording the gap of the coupling for the alignment
purposes.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 48

49. Check swing check value of the HP rotor with alternate bolts in position. The
above value must be within the prescribed limit only otherwise a
correction must be carried out at site in consultation with designer.
Ensure free movement of rotor on their bearing. Do not rotate the
is tight during its rotation.
rotor if it
Ensue that the coupling holes are properly aligned to avoid unnecessary
enlargement of holes.
Ensure HP-IP-LP rotor radial run out after tightening with alternate clearance
bolts. Release the couplings for reaming / honing of couplings.
In case of spring loaded TG decks, refer alignment procedure
0909G
T1-08-
REAMING / HONING OF COUPLING
Ensure that there is no disturbance on coupling during reaming/honing
operation.
First ream/hone two opposite holes of the coupling and install two pins/bolts
with sliding fit and then take up all other holes.
Enlarge coupling holes to the minimum possible diameter and try to make all the
holes to same dia.
Ensure that the finished holes are straight and there is no banana shape. This
can be ensured by checking hole with a straight ground finish pin having
0.02/0.03 mm clearance.
The length of the pin should be equal to the bolt length. In case, few holes have
gone considerably over size during reaming/honing at site/works, do not
enlarge all the holes. As a special case in such cases these few holes
may be left as oversize.
Ensure that the holes during reaming/honing are perfectly finished as ground
bore and size obtained should be within 0.005 mm. Ensure all the coupling
bolts are fitted within 0.02/0.03 mm clearance with sliding fit and bolts are
to be ground within an accuracy of 0.005 mm.
Coupling bolts are not to be hammered in the holes and these are to be fitted with
thumb pressure only.
Do not decouple the coupling in any case without ensuring the fitting of all the
coupling bolts.
BALANCING OF COUPLING BOLTS
After fitting the coupling bolts in all the holes these are to be balanced within 5
gms accuracy and an accurate balance which can take a load of about 20 kg.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 49

50. may be used. During balancing of coupling bolts following points are to be taken
care.
Final balancing of the coupling bolts are to be done along with the coupling
nut of individual bolt.
If all the coupling bolt hole sizes are same before/after reaming and honing
then all the bolts can be kept of equal weight.
If necessary adjust the weight of the bolts by machining the metal from the bolt
head.
When the holes of the coupling are of different sizes then it must be seen that
whether excess enlargement have been done at site or works. In such
cases if excess cutting have been done at site in a particular hole then
coupling bolt with excess weight are to be used. The amount of excess
weight must be equivalent to the excess enlargement of hole at site. If a
particular hole of excess dia. is noticed from factory then it is assured that
the particular rotor is balanced with excess dia hole and there is no
need of providing excess weight bolt at site.
COLOUR MATCHING OF THRUST BEARING
After completion of reaming/honing and preliminary tightening of the coupling
bolts, the colour matching of the thrust bearing pad have to be carried out with
respect to the thrust collar of the HP Rotor. During colour matching a good
contact on all the pads of front and rear side are to be ensured with respect to
rotor collar by moving the rotor in +/- direction during its hand rotation. Following
points are to be taken care during colour matching.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 50

51. Thrust bearing must be axially locked with the help of axial keys during the
colour matching of the pads. Axial keys to be fitted while finalising the
alignment of thrust bearing with rotor collar without pads.
Few drops of oil is to be put on journal portion of the thrust bearing during
rotation of rotor to ensure that the oil is not entering in pad portion of the
bearing.
Colour is to be applied on the thrust collar of the rotor.
If necessary move the spherical support of the bearing pedestal to ensure the
equal thickness of the pads before fittment of axial keys of the bearing.
During moving of the spherical support in front or rear direction ensure that
there is no left - right movement to the support otherwise that may
cause misalignment of the bearing.
After colour matching of the thrust pad the axial zero position of the rotor is
achieved and this can be taken for all other future reference for setting of
axial position of HP, IP & LP casing.
HP, IP and LP lower casing are to be set axially after fixing the axial position
of the rotor and their final axial keys can be installed at this stage.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 51

52. ALIGNMENT OF HP, IP & LP CASING
After completion of colour matching of the thrust bearing pads the casing
alignment work can be taken up. The following points are to be taken care
while aligning HP, IP and LP casing.
The roll check have to be carried out in HP, IP and LP casing to ensure the
correct radial clearances of the casing.
TG deck springs are to be kept in floating condition while recording the roll
check of LP casing. However the roll check of HP/IP casing may be carried
out before floating of TG deck for fitting of their radial keys but up and
down roll check of HP/IP casings are to be done with TG deck in floating
condition as per the procedure TS/ST/ 01/0008/00/96.
Ensure that there is no obstruction in the movement of LP inner casing due to
welding of any of extraction piping. The one of the joint of extraction
piping may be left free till completion of roll check of the casing.
The welding of steam inlet pipes between LP inner casing and LP girders are to
be taken up after completion of roll check of the casing.
HP, IP and LP casing are to be fitted with final packers and axial key immediately
after the roll check. During fitting of casing axial keys and palm packers
ensure proper contact on lubrite coating of the keys/packers to avoid any
damage of these coating during operation of the machine,
After completion of fitting of final keys and packers only the casing are to be
cleared for further works of welding of various pipe lines.
The gland steam, balancing leak of lines, steam inlet and exhaust pipes are to
be welded with HP casing after fitting of final axial keys and packers of the
casing.
Center HP rotor w.r.t. casing front and rear spigots. Compare the readings with
shop protocol and record the readings.
Offset center line of the HP, IP & LP casing w.r.t. respective rotor center line as
per recommended logsheet.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 52

53. Check/record LP diffusers centering readings after roll check of the casing.
Before roll check of LP casing all the stiffener pipe welding work must be
completed. Refer T1-08-0909G.
FINAL TIGHTENING OF COUPLINGS
In case of spring loaded foundation after completing all other works the HP / IP ,
IP/LP , LP/GEN , GEN/EXCITER couplings are to be reopened and realigned
after completing the reaming /honing . The rotors alignment are to be checked
with TG deck in floating condition
as per the laid down procedure. After
checking of alignment /catenary the final couplings are to be tightened including
their coupled run out and swing check of rotors on HP front and Exciter end of
the shaft.
BOXING UP OF LP INNER INNER AND LP INNER OUTER
CASING
The boxing up of LP inner inner and LP inner outer casing can be taken up
before starting the alignment of HP-IP & LP rotor for coupling work. The
following points are to be taken care before/during boxing up of these two
casings.
Ensure matching of all the parting plane holes, fitting of cap nuts and
accessibility of spanner .
Ensure feeler tightness of the parting plane joint of both the casing.
Check/record all the radial and axial clearances of the casing.
Ensure proper cleanliness of the LP inner inner and LP inner outer casing.
Ensure adequate clearance between LP inner inner casing and LP inner outer
casing to avoid any obstruction during expansion of the LP inner casing
inside the LP inner outer casing during operation of machines.
BOXING UP OF LP OUTER CASING
During the boxing up of the LP outer casing following points are to be taken care.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 53

54. Roll check of LP inner casing including the fitting of key, packers etc. must be
finished.
All the works must be finished inside the LP casing before boxing up of LP
casing including LP extraction pipe line works.
Ensure matching of all parting plane holes and feeler tightness of the joint
before boxing up of the casing.
Ensure feeler tightness of bursting diaphragm flange joint before boxing up of
the casing.
Ensure proper assembly of parting plane rubber cord.
FINAL HORN DROP CHECK
After completing the welding of HP inlet, HP exhaust, IP inlet, IP exhaust
and other piping of HP/IP casing the final horn drop readings are recorded
as per the laid down procedure mentioned in the manual for horn drop
check. However the IP casing horn drop is also to be recorded with IP
inlet upper half pipe welded with casing alone.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 54

55. Grouting of turbine base plates, bearing pedestals, foundation frame with shrink-free
grouting compound is intended to ensure uniform transmission of the force and vibration
of the TG unit to the foundation.
Caution:
Preparations for grouting, and grouting must be carried out with great care as it is no
longer possible to check and rectify the parts once they have been grouted.
CONBEXTRA GP-II or equivalent should be used as grouting compound.
Further
details on the grouting depths, mixing time, quantity of water to be mixed, should be
refereed from the manufacturers brochures.
PROCEDURE
The foundation should be thoroughly cleaned. All foundation bolt holes should be filled
with pea-gravels and covered at the top to avoid entry and sticking of grouting materials
with the bolts.
NOTE:- Remove all rust preventive paints, grease etc. from surfaces by wire brushes
to ensure proper adhesion of the grouting compound.
SETTING UP OF SHUTTERING
Set up shuttering from suitable material in box like manner around the foundation plates
and secure it firmly.
NOTE:- Shuttering must be sealed well to prevent the liquid grouting compound from
running out. This can be done by using paste of grout materials and allowing it sets.
As the grouting compound remains workable for a limited time, to prevent air bubbles, it
must be poured from one side only. For this, a large size filling heaped should be used.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 55

56. PREPARATION OF GROUT MIX
Following measure must be taken before commencing mixing and grouting due to
limited time that the grouting compound remains workable.
Keep the foundation moist for at least 6 hours before the grouting.
-Set up mixers in the immediate vicinity of the foundation plates. The capacity of the
mixers, should be adequate to cope with the quantity of mixed cement required at a
time. Two or more mixers are required for grouting of bearing pedestal foundation
frame.
-Store the grouting compound next to mixer.
- Ensure that the compound is well within its expiry date.
-Provide the water hose and measuring pans near the mixers.
-Ensure uninterrupted power supply to the mixers and EOT Crane for handling the
ready mix.
-Provide adequate workmen for grouting.
-Ensure six empty cubes for filling the grout for strength testing. This is to be done as
per recommended FQP
-Take 80 % of the required water quantity first in the mixture. Then add gradually the
grout, ensuring that no lumps are found. It is desirable to add five or six large sizes
stones to break any lumps. Finally add the balance quantity of water and mix for atleast another five minutes
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 56

57. This mixture is then taken into through heaped mesh. The hopper must be big enough
to make the full quantity of grout.
Than pour the grout with a hose through the filling hopper until the desired height is
achieved on the opposite side. (Flow may be accelerated by moving the grout in the
filling nozzles underneath the plates with chains or material strips.) This should be done
only if it is permitted by the grout supplier.
CAUTIONS
1. Do not use concrete vibrator.
2. Pour grout from one side only so that no air bubbles remains entrapped in the
grouting compound.
3. Due to short workability times, never mix more grouting compound at one time than
is required for one plate or volume to be grouted.
4. Pour in one continuous operation, without interruption.
5. Do not install any woven steel fabric reinforcing mats beneath the foundation plates.
6. It is desirable that in hot weather the grouting is done in the evening so that ambient
temperature is low during the initial setting time.
7. Water should be clean and free from dissolved chlorides, as these weaken the grout.
8. In case during the grouting operations heavy leakage is observed from the shuttering
that cannot be plugged during the grouting operation, and the level of grout has
fallen below the base plate level, it is desirable to wash out the complete grout. The
operation should be repeated after the shuttering has been rectified.
NOTE:- After at-least 72 hours setting time, work may be commenced on pretensioning of the foundation both.
After the grouting compound has set (approximately. 24 hours after grouting), remove
all shuttering and smooth off the excess grout. The grouting compound is subjected to
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 57

58. compressive forces only.
Resultant hair cracks are insignificant with regard to TG
stability. These can be avoided by covering the exposed areas of grout by polythene
sheets to avoid excess loss of moisture during initial setting.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 58

59. ASSEMBLY PROCEDURE OF IP MODULE
Due to oversize dimension of the IP module (M30 - 63) and its limitation in
transportation from Hardwar to site, the same will be dispatched to site in dismantled
condition in various packages after completing the shop assembly at Hardwar. First
the complete assembly of IP module will be done at works except the heat tightening of
parting plane bolts of IP inner and IP outer casing. Afterward complete casing will be
dismantled and dispatched to site.
The above machines are equipped with the spring loaded foundation deck.
As a
general requirement initially all the turbine and generator rotors will be aligned/coupled
without floating the TG deck. The coupling will be opened and again re-aligned after
floating of the TG deck which is generally done after erecting all the components of
Turbine -Generator including their piping etc.
ASSEMBLY PROCEDURE AT SITE :
Place IP outer casing lower half in position after its cleaning over the pedestals by
supporting it on the Jacking screws at four corners of casing. Additionally
support the casing on temporary packers with the pedestals also.
Align IP outer casing radially with the help of piano wire keeping the HP rear and IP
front pedestals seal as reference. Install temporary radial keys of the IP outer
casing with the pedestal.
Clean and install IP inner casing lower half along with its radial keys (Drg. No. 0-106-0127500 item No. 25) of front and rear end. During placement
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 59

60. of inner casing support it on its four nos. Jacking screws. (Drg no. 0-106-0127500# 18). After placement of inner casing install its axial keys (drg N. 0-10601-27500 # 20). Before placement of inner casing install its thermocouple,
parting plane studs (drg N. 0-106-01-27500 # 33 & 34 ). Seal ring of inlet insert
& extraction line (drg N. 0-106-01-27500 # 3,4,9,10,13,14 ).
Place IP inner casing upper half in position and tighten alternate parting plane bolts.
During this process the heat tightening the bolts are not necessary as this is
required for ensuring the feeler tight parting plane joints of the IP inner casing.
The IP inner casing packers are also to be installed during tightening of the P/P
bolts and load of the inner casing is to be transferred on these casing packers
(drg N0-106-01-27500 # 17) fter taking the load on the packers release the
jacking screws of the IP casing.
Loosen IP inner casing parting plane bolts and remove IP inner casing upper half.
Before loosening the IP inner casing parting plane bolts support inner casing
again on its four jacking screws and ensure that the parting plane level of lower
half inner casing is not disturbed and remain same as it was kept after tightening
of parting plane bolts with load on its four packers.
Place IP rotor in position after its cleaning. The front end of the rotor is to be placed
over segment (drg N. 0-106-01-27500 # 21) and rear end of the rotor on its
bearing. During placement of IP rotor ensure that the rotor is free on its seal fins
of IP inner casing and necessary the IP outer casing may be lowered on its rear
end.
Provisionally align and couple HP/IP/LP/ Generator rotors and complete reaming
/honing of the coupling including swing check etc. Before rotation of IP rotor
remove segment (drg N. 0-106-01-27500 # 21).
Set axial position of the IP rotor as per the zero position of the thrust bearing and set
axial position of the IP outer casing as per Hardwar protocol on front and rear
end of the IP outer casing.
Align radially IP outer casing with reference to the IP rotor on front and rear glands.
Recheck/correct axial position of the IP casing.
Assemble IP inner casing upper half end tighten the alternate parting plane bolts to
ensure feeler tight joint.
Do roll check of IP inner casing by moving the IP outer casing in left/right direction and
IP inner casing itself in up/down direction with the help of inner casing jacking
screws by removing the inner casing packers. Ensure / compare roll check
values with shop records.
Check IP rotor axial float in IP inner casing and compare with shop protocol.
Loosen IP inner casing bolts and remove IP inner casing upper half.
Decouple and lift IP rotor for assembly of rear end shaft seals of IP casing. The front
end of the seals may also be assembled now of afterward with the IP rotor in
position.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 60

61. Place IP rotor in position and provisionally couple it with HP rotor on temporary bolts.
The IP rotor may not be coupled at its rear end with the LP rotor at this stage.
Assemble and heat tighten IP inner casing upper half as per required elongation of
parting plane bolts. Install seal rings of inlet insert and extraction pipe on IP
inner casing upper half (drg N. 0-106-01-27500 # 1,2,7,8,11,12). The taper pins
of IP inner casing parting planes are to be removed before placement of IP outer
casing upper half after the heat tightening of IP inner casing bolts.
Assemble IP outer casing upper half and tighten the parting plane bolts to ensure feeler
tight joints. The heat tightening of the bolts are not to be done now. Before
placement of IP outer casing upper half assemble casing shaft seals of front &
rear end also.
Do roll check & float of completely assemble IP turbine and compare it with factory
protocol.
Heat tighten IP outer casing parting plane bolts to required values, and carry out final
roll check and float of completely assembled turbine.
NOTE : These are general instructions for the assembly of IP
module M 30 - 63 at site. However, depending on the site
conditions the same may be suitably reviewed, if necessary.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 61

62. SEALING & ANTISIEZING COMPOUNDS
SNO
LOCATION
01
JOINT PLANE OF HPT IPT
& VALVE CASINGS,
GLAND BOXES &
STRAINER HOUSINGS,
BREECH NUT MATING
FACE.
JOINT PLANE OF LP
OUTER CASING
(WITHOUT RUBBER
SEALING CHORD).
JOINT PLANE OF
BEARING PEDESTALS,
MOP CASING, VALVE
SERVOMOTOR.
METAL TO METAL
JOINT IN HIGH
TEMPERATURE
ZONE
− BIRKOSIT
− STAG B
− MAGNESITE
COMPOUND OF
BHEL BHOPAL
METAL TO METAL
JOINT IN LOW
TEMPERATURE
ZONE
METAL TO METAL
JOINT IN OIL
ENVIRONMENT
− HOLDITE
− LOCTITE 574
THREADED FASTNERS
INCLUDING, BREECH
NUT THREADS, KEYS,
PACKERS, DOWEL PINS
U & I - SEAL RINGS IN
HIGH TEMPERATURE
ZONE.
THREADED FASTNERS,
KEYS, PACKERS, DOWEL
PINS IN LOW TEMP.
ZONE, COUPLING BOLTS
SEAL SEGMENTS, HP/IP
CASING PALM PACKERS,
HP FRONT & REAR
BEARING PEDESTAL
PACKERS (OTHER THAN
SELF LUBRICATED
LUBRITE PACKERS).
HIGH
TEMPERATURE
( < 350°c)
ANTISIEZING
− MOLYKOTE P37
− OKS 255
02
03
04
05
FEATURES
LOW
TEMPERATURE
( < 350°c)
ANTISIEZING
RECOMMENDED
COMPOUND
− HYLOMER
− GOLDEN
HERMETITE
− VICTOR
SHELLAC
− MOLYKOTE D 21
− OKS 511
− MGS 400
NOTE: NO COMPOUND IS TO BE APPLIED ON SELF LUBRICATED LUBRITE
PACKERS.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 62

63. ASSEMBLY OF BEARING AT SITE
GENERAL DESCRIPTION
The KWU design machine are supplied with four bearings out of which three are the
journal bearing and one is combined thrust and journal bearing on H.P. rear end of the
shaft. All the turbine bearing are self aligning type and they adjust themselves as
per the catenary of the machine.
The function of a journal bearing is to support the turbine shaft , but the thrust
bearing support the shaft as well as work as a fix point for the turbine shaft. The contact
arrangements between bearing and bearing supports are of two types i.e. sphere to
sphere in HP front and HP rear bearing and torus to cylindrical in other bearings.
The bearings are supplied to site after ensuring their contact at works. During erection
all the bearing are supplied to site in aligned and assemble condition in their individual
pedestal from the works. After alignment of the bearing in their pedestal the seat of
the bearing are doweled before dispatch to site.
In case of Thrust and Journal bearing the seat of the bearing neither doweled from
the works nor it is recommended to be doweled at site. The bearings need
preparation before placement of module in position at site. This can be done even
before the placement of pedestal in position for grouting.
ASSEMBLY PROCEDURE
1.
After opening the pedestal remove and clean the bearing including its
spherical/ cylindrical seat.
2.
Remove oil guard ring and its duct and keep them in proper place
for their storage at site.
3.
Handle bearing carefully to avoid any damage to the babbit and
its torus/spherical piece. During storage at site avoid direct loading of
bearing on its torus. A thick rubber seat may be used during
handling of bearing at site on its torus.
4.
Ensure 0.03 feeler tightness on bearing parting plane. In case of
any variation the matter may be referred to designers.
5.
Measure bore dia of the bearing and journal dia at site and ensure
the oil clearances. If any discrepancy is observed , designer may be
referred.
6.
Ensure torus/spherical contact with their seats at site. While checking
the contact the seat may be bolted with their pedestal. In case
variation contact from their specified diagrams are noticed then
following may be carried out at site:a)
In case of torus to cylindrical seats the line contact are
recommended by designers. If these lines are not straight
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 63

64. and are in angle then the bearing may be rejected straight way
and sent to works for rectification. These line contact may be in
a width of about 20 mm throughout on its seat leaving with
area on both sides. The contact may be wide in Center and then
gradually reducing on sides. In case there is no contact is
achieved in the center and only sides are having contact then
a feeler gap may be recorded in bottom. In case if the bottom
is tight to a feeler of 0.03 mm the bearing may be accepted
at site without doing any rectification.
b)
In a reverse case the contact are achieved in center only
though the 0.03 feeler is not going in the side. The bearing
may be still accepted at site. In case if the feeler is going in the
bottom or in sides by 0.03 mm. the bearing are not accepted at
site and can be sent back for the rectification to the works.
Similarly if the contact are intermittent on its seat but in a
straight line and no feeler is going the bearing may be accepted.
In case of very wide contact also the bearing may be sent back
for the rectification. While checking these contact very light
color may be put on torus of the bearing. Before sending back
the bearing to the works the matter may be referred to
designers and their concurrence is to be obtained. No
scrapping/lapping is recommended in these bearing for
improvement of the contact.
c)
In case of spherical to spherical bearing the contacts are called
in the center like a moon shape. In these bearings even full
contact may be accepted. But in case if there are contact on
sides and a feeler gap is noticed on center then the bearing
may not be accepted.
In such cases if the gap is upto 0.03 mm then the
matching/lapping may be carried out at site. But in case of higher
gap the matter may be referred to designers. In case of reverse
case if the feeler gap of 0.03 is noticed on both sides of the
bearing the bearing may not accepted at site and matter may be
referred to designers.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 64

65. 7.
Before checking the contact between torus and its seat ensure that the
seat is feeler tight to 0.03 mm without tightening of any bolts with the
pedestal. If necessary this may be corrected with consultation of
designers. Similarly ensure contact between torus spherical piece
with bearing and in case of variation the matter be referred to
designers and no correction is to be carried out at site without the
approval of manufacturing unit.
8.
Before checking the contact between torus/spherical piece with
bearing and in case of variation the matter may be referred to
designers and no correction is to be carried out at site without their
recommendations.
9.
The sizes of all the shims may be punched in bearing body and
spherical/torus piece of the bearing. The number of shims are to be
limited to 3-4 numbers only even after complete alignment of
machine. A protocol for number of shims may be prepared.
10.
Torus/spherical should not have any radial movement over its
bearing. This can be seen after opening the torus from the bearing.
11.
Check jacking oil lines of the bearing and clean them thoroughly.
Ensure jacking oil lines fittings also for their male female threads
etc otherwise this may create the oil leakage through these lines
during operation of the machine. The jacking oil pocket in the
bearing may be checked if necessary they may be corrected at site as
per the drawings.
12.
When ever JOP is not available, use always thick oil during rotation
of shaft over bearing.The type of oil may be used as servo cylinder
1000 grade of IOC.
13.
After installation of bearing in position the oil clearances may
be checked after few rotation of the shaft. But the final oil clearances
are to be checked after final coupling of the shaft. In case of
variation in side oil clearances no cutting of babbitt metal is
permitted at site. Any variation in clearances may be counter
checked by measuring journal / bearing bore dia. Bearing bore dia is
to be measured by assembling and tightening of top & bottom halves
of bearing.
14.
In case of skew side oil clearances, the investigation may be carried
out, if necessary consult manufacturing unit.
15.
Ensure good contact between journal and babbitt metal of the
bearing in the center. Any minor high spot may be removed from
the babbitt metal while checking with blue color. Ensure full
contact of shaft over the jacking oil pocket also.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 65

66. 16.
Always cover rotor journal with the upper half bearing to avoid
entry of any sand particles etc. in the bearing . During pouring of
oil the upper bearing may be removed and replaced back after the
pouring of oil.
17.
After completing the reaming/honing and final tightening of
coupling bolts the work of bearing side pad, yoke keys and oil guard
fitting may be taken up.
18.
Before starting the side pad and top keys ensure that the bearing is
perfectly level on parting plane. Ensure that the gap for the side
pads are parallel otherwise these are to be made by
cutting/scrapping.
19.
After fitting of the bearing cap if the gap for the radial top keys are
in taper a proper correction is to be made here. The bearing cap
may also be repositioned to achieve the parallelity of the key way.
The cap may be re-doweled after repositioning it but no taper are to
be left on these area. If repositioning of cap is not helping then the
cutting may be carried out in bearing cap.
20.
The gap for the top packer of bearing may also be checked. In case
of any taper the same is to be corrected by cutting on bearing cap.
Sometime the size of this packer comes to very low i.e. even below
5.00 mm. This may be corrected by matching the cap and size for
this packer may be kept around 6.00 mm.
21.
On all these bearing cap key a proper fitting and clearances are to be
maintained during assembly. These key of proper material are to
be only used and no welding deposits are permitted here. The new
key may be made at site by EN-24 material if correct key are not
available at site.
22.
Use of local made shims in bearing may be avoided and shims
supplied from the works with proper cutting of holes are to be used.
Ensure drawing requirement of maximum adjustment at site by +
0.3mm in shim size from manufactured condition.
23.
A proper care should be given during fitting of bearing oil guard ring
otherwise it causes the oil leakage during operation of the machine
through pedestals. Parting plane joint of oil guard ring and duct
should be feeler tight and no elongation of holes on these area may be
permitted.
24.
The bearing parting plane bolt are to be tightened to required torque
only no other method of tightening of these bolts may be used.
25.
Adjustment of shims between spherical/torus and bearing body is
limited to +0.30 mm in up and down and left, right direction. this
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 66

67. margin may be left for emergency work during overhauling of the
machine any adjustment during erection and normal overhauling
may be done by adjusting shims between spherical/cylindrical seat
and pedestal base only. For left and right adjustment the complete
pedestal of HP front and HP rear may be moved with the help of
their radial keys.
The above discussed points were common for Journal bearing
and combined thrust and journal bearing. Now some specific
points are detailed here for the assembly of combined Thrust
and Journal bearing:
• Remove all the thrust pads before placement of bearing in
position and store them in a proper place.
• Pressure proper fitting of babbitt metal liner in the bearing body
including necessary pinch in the fitting of its liner.
• During alignment of rotor along the bearing with respect to the
shaft by moving spherical seat of the bearing radially and axially.
• No elongation of holes are to be carried out in spherical sat of
the bearing for the purpose of its alignment.
Before deciding axial position of the bearing the axial position of the rotor is to be
determined. If necessary the H.P. rear pedestal as a whole may be shifted axially
to ensure correct position of the thrust bearing.
•
•
•
•
•
•
•
•
Align the thrust bearing in such a way that the thrust pad gap
achieved are prallel and no difference are noticed in front and rear
pad thicknesses.
Movement in the thrust pad should be ensured and a difference in
thickness of packers including shims should be with in + 0.10 mm
may be permitted on front and rear pad sizes in exceptional cases.
After ensuring the perfect alignment of the bearing the axial keys
are fitted after assembly of upper half bearing. These axial keys
are to be fitted in perfect parallel slots without any clearances.
The keys are to be fitted in such a way that there is no movement
to the bearing during fitting of these axial keys. Necessary dial
gauges are to be installed on bearing during fitting of these keys.
After completion of axial key works of the bearing the thrust pads
may be fitted in the bearing with a clearance of about 0.10/0.15
mm.
Before fitting of pads in the bearing ensure that there dimension
are made parallel to suit the front and rear slot size of the bearing
(size between thrust collar and bearing body).
Ater fitting of pads in the bearing ensure their free movement
over the bearing.
Install lower half bearing in position along with their pads and put
very small quantity of oil on journal then rotate the rotor and put
blue color on the thrust collar of the rotor on both front and rear
side.
Install upper half bearing along with all pads and fix their axial keys.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 67

68. • Rotate the rotor and move + direction axially with the help of
wooden planks. Remove both halves of the bearing and see the
blue contact on thrust pads. If necessary some cutting may be
carried out on the pads to achieve the color contact. This
exercise may be repeated few times to achieve the blue contact
• Ensure a float of 0.30 + 0.10mm during color matching of the
thrust pads. If necessary the minor adjustment of shims may be
carried out in the bearing pads.
• Before installation of thrust bearing along with thrust pads in
position the both halves may be bolted out side and their pads
may be checked for color contact over a surface plate also in
front and rear both sides. This will reduce the time cycle while
carrying out the color contact of the bearing with the rotor.
• During overhauling of the unit the bearing contact are to be
rechecked and need correction. In case of torus to cylindrical
type of bearing if the contact are not satisfactory then the
bearing and its seat may be remachined at works. In spherical
to spherical bearing the variation in contact if noticed can be
corrected by matching/lapping at site. Sometimes the heavy
pitting marks are also noticed on same of the bearing and these
need correction by machining it.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 68

69. Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 69

70. Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 70

71. Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0801G
Page No. 71

72. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(BUMP CHECK)
ERECTION
BUMP TEST
The axial clearance check is determined after radial clearance measurement has
been completed.
In this case the shaft is shifted in the “+” and “-” directions from its operating
position and the dimensions with the shaft in limit position are measured using a
depth gauge.
Note: Enter the measured values ( actual dimensions ) on the record sheet and
compare them with the specified dimensions.
If the deviations from the specified dimensions is greater then the permitted
tolerances, the manufacturer must be consulted.
Note : Based on the readings of bump check, axial position of the shaft wrt
casing is not to be altered.
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0802G
Page No. 72of 40

73. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(ROLL CHECK)
ERECTION
ROLL CHECK
GENERAL DESCRIPTION
In KWU machine the minimum radial clearances HP, IP and LP casing are measured
by actually by moving the casing radially at site while rotor is rotated by hand. This is
a very accurate and fast method of measuring the minimum radial clearance of any
of the casing.
The major variation in these reading may cause vibration in the machine and
obstruction in barring gear operation etc. Such facilities are not available in many
other designs of machine and causes longer duration in erection and overhauling of
the units.
After completing the alignment of rotors the casing alignments are carried out by roll
check method but equal importance should also be given to the centering of HP and
IP casing.
The centering of casing may not be fully sacrificed in comparison of rolling test
readings and a compromise between these two readings should be made. The rolling
test should be carried out in cold machine only.
PROCEDURE
ROLL CHECK OF HP AND IP CASING
1.
Alignment and coupling of HP-IP and LP rotors are to be
completed before starting the rolling test of the casing in normal
case but this can be done without coupling of LP rotor also.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0803G
Page No. 73of 40

74. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(ROLL CHECK)
ERECTION
2.
Centering of the casing on HP front, HP rear IP front and IP rear
spigot are also to be completed before starting of the rolling test.
These readings can be compared as per the factory protocol also.
Fix temporary radial and axial keys of the casing before rolling test
of casing. During dialing on spigot a proper care should be taken
that the dials are properly mounted over the fixture and the
fixture fabricated at site is strong enough to give the correct
readings. The point dial indicator may be used here for the better
results of the dial readings.
3.
All the four jacking screw of HP and IP casing are to installed along
with dial gauges for monitoring of up and down, and left and right
movement of the casing.
4.
One number hydraulic jack on each corner of the casing along with
a spanner on each corner for jacking screw are also to be made
available.
5.
During erection of machine the turbine rotor are generally rotated by
hand with the help of periphery holes on coupling. Two pipes of
about 1250 mm long along with a pin to suit the dia of periphery
may be used for rotating the rotor shaft. The initial jerk to the
rotor is given by the help of crane and it is further rotated by these
pipes through periphery holes of the coupling. During overhauling
generally the jacking oil system is available and the rotation of rotors
are achieved with the hand barring of the machine.
6.
Before starting the rolling check it should be ensured that the rotor
shaft is absolutely free on manual rotation/hand barring as the
case may be. During manual rotation two persons are to be
employed for this work and during hand barring only one person is
enough.
7.
Always use thick oil for rotation of rotor over bearing in absence of
jacking oil system. The type oil may be servo cylinder 1000 grade
(IOC) oil.
8.
During the rolling test the temporary casing packers are to be fitted
with about 1.00 mm shims.
9.
During the rolling test of any one of the casing the same is lifted first
on all four corners in a step of 0.05 mm with the help of hydraulic
jack and jacking screw. The rotor is also rotated manually side by
side with the lifting of casing. The rotation of rotor and lifting of
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0803G
Page No. 74of 40

75. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(ROLL CHECK)
ERECTION
casing continued till it becomes little bit tight on the seals of the
casing
After this the casing is lowered by about 0.05mm and rotor is
rotated again if it is completely free. In case the rotor is still tight on
its manual rotation the casing is further lowered by 0.05 mm on all
four corners. After ensuring the freeness of rotor it is again
rotated and casing is lifted simultaneously on front end till the
rotor rotation becomes tight on seals portion of the casing.
As soon as the shaft becomes tight the lifting of casing and
rotation of shaft is stopped and dial readings on front end are
recorded. The average lift on front end of the casing is the bottom
clearance on front end of the casing.
After this the casing on front end is lowered by 0.05 mm and
freeness of rotor is ensured. In case it is still tight the casing is
further lowered by 0.05 mm. On front end and the freeness of
rotor is achieved. Now the rear end of the casing are lifted similar
to front end and bottom clearance of rear end are recorded . After
recording the bottom clearance of front and rear end of
individual casing the casing is lowered with the help of hydraulic
jacks and jacking screws to its original zero-zero position.
Repeat similar operation of rotating the rotor and lowering the
casing on front and rear end for deciding the top clearance in front
and rear end of the casing. Before starting the rolling test in
downward direction of the casing remove about 1.00 mm shims
from each packer of the casing, but kept the casing on
hydraulic jacks and jacking screws on its original position. The
casing is again brought back to its original position by
installation of the shims back to the packers of the casing after
recording the top clearances of the casing.
After recording the up and down rolling test values the radial
keys of the casing are removed and again rolling test for left
and right direction are done similar to up and down. During this
process the radial dial on the casing are also installed. After this
check the casing is brought back to its zero position in radial
direction also.
After completing the rolling test readings of one of the HP/IP
casing in up/downand left/right direction the clearances are
readjusted as required at site in radial direction by moving the
casing with the help of temporary radial key or shims on the casing
packers. The casing is then locked on four corners and final dial
readings of spigot are recorded on front and rear end. Immediately
after this the final radial key of the casing are fixed and the
locked of the casing are released for fitting of the final casing
packers. The final spigot dial reading are repeated and confirmed
with the earlier readings.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0803G
Page No. 75of 40

76. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(ROLL CHECK)
ERECTION
10.
After doing the full rolling test and fixing of a final radial keys
and packers of one of the casing the rolling test of another casing is
done including the fitting of final keys and packers.
11.
Necessary offset in the radial clear-ance is also kept before fitting
of final packers of the casing toward the lift of the shaft during
operation of the unit.
12.
No inlet and outlet pipes are to be welded with the casing till
completion of rolling test and installation of final keys and packer
of the casing.
13.
Radial clearance of the casing are to be ensured with reference to the
factory supplied protocol also.
14.
After fitting of final keys and packers of the casing the final spigot
dial values of HP front, HP rear, IP front and IP rear casing are
to be recorded for future reference in the protocol.
15.
The horn drop readings are also to be checked after the fitting of
final packer of the casing.
16.
In case of IP casing the roll test readings are to be taken with the
IP front end rear shaft scales. The spigot dial readings are also to be
taken over the spigot of shaft seales.
17.
During rolling test of the HP and IP casing if the rotor is rotated over
the jacking oil then the adjustment of readings are to adjusted for
the lift of the rotor also.
18.
Four numbers 1.00 mm undersize packers for HP & IP casing may
be made during erection and supplied to customers as T&P items
for further roll test during overhauling of the unit. If any taper is
left on final packers of the casing then these four packers may be
made to similar taper also.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0803G
Page No. 76of 40

77. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(ROLL CHECK)
ERECTION
ROLLING TEST OF L.P. INNER CASING
1.
The rolling test of L.P. inner casing is done similar to the HP or IP
casing but both side joints of L.P. inlet bellows are kept free or
bellow itself are not positioned at all, till completion of rolling test.
But during overhauling the rolling test is done with already welded
bellows.
2.
Rolling test of L.P. inner casing is done after the neck welding of
condenser andstiffener pipes inside the condenser. This include the
welding of stiffener pipes of L.P. casing and gusset plates also.
3.
After rolling test of the casing the final radial keys of the Gusset
block and casing packers on all four corners are installed.
4.
Necessary offset in the radial clearances of the casing is also kept
before fitting of final L.,P. inner casing packers.
5.
Radial clearances of the casing are to be ensured to the design values.
In case of any variation the matter may be referred to the designers.
6.
If the rotor is rotated on jacking oil then the rolling test readings
are to be adjuted for the lift of the rotor also.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0803G
Page No. 77of 40

78. STEAM TURBINE
500 MW
ERECTION
CRITICAL ACTIVITIES
(CATENARY AND ALIGNMENTS)
CATENARY AND ALIGNMENTS
General Description
The catenary of the machine is very important for a turbine and Generator assembly
to achieve proper alignment of various rotors and loading on their bearing. Any
deviation may lead to various operational problem in the machine like high shaft
vibration, high bearing vibration, high babbitt metal temperature of the bearing etc. To
avoid these problems it is necessary to maintain the catenary of the machine during
erection and subsequent realignment/overhaul of the unit. Many times it is observed
that though the alignment of rotors are within limit but the catenary as a whole get
deviated from the prescribed design value of the machine. In order to avoid such
derivation a need is felt to devise a procedure which shall ensure rotors alignment
alongwith proper catenary of the machine.
During first few years of the operation of the unit the possibility to the disturbance
of the catenary are much more due to settlement of the foundation frame.
In each overhaul of the unit the catenary of the machine is to be corrected. The L.P.
front and L.P. rear pedestal are directly grouted here without any separate base
plate. As such any correction on lifting or lowering. These pedestals are not very
convenient so if necessary the rotor may be lifted or lowered with respect to pedestal
seal bore and required catenary may be achieved. In extreme cases these pedestals
may be even regrouted during major overhauls of the unit to correct the catenary of the
machine.
Procedure
1.
Install a bench mark plate near L.P. rear pedestal as height of
the machine center line with the consultation of civil Engrs at site. A
plate of 200 m.m x 300 m.m size with 20 m.m thickness
machined/ground on top side may be welded over a I Beam or a
channel in level condition. This plate is to be installed very carefully
as this will be a future reference for setting up the all elevation of
the machine.
2.
Record half bore error of all the four pedestals and confirm the
readings with the factory records also. The half bore error may be
checked in both upper half and lower half of the pedestal and same
may be punched on both halves in left and right side for all
future references of the machine.
3.
During alignment of pedestal at the time of grouting with conbextra
cement set the height of the pedestals as per required catenary of
the machine considering +value for the half bore error of the
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0804G
Page No. 78of 40

79. STEAM TURBINE
500 MW
ERECTION
CRITICAL ACTIVITIES
(CATENARY AND ALIGNMENTS)
pedestals. While setting the height of the pedestals it should be kept
in mind that the height for the center of the pedestal bore are to be
kept as per the catenary of the machine not the parting plane of
the pedestal.
4.
For better results four water level jar connected to each other with
a polythene pipe may be installed on each pedestal. The D.M., water
may be used here and leakage through polythene tubes should be
avoided fully while making the connections. These jars may be
fabricated at site by about 125 mm. dia pipe with a plate welded in
bottom and then machined for better seating on pedestal base. The
height of the jar may be kept as about 175 mm. A depth
micrometer installed and clamped over a magnetic base is also
required for measurement of the water level in the jar. The
micrometer point is to be made very sharp by grinding it. Here the
magnetic base of the 0-10mm dial gauge may be used.
5.
.During measurement of water level in the jar the micrometer is to be
kept approximately in center of the jar. The micrometer along with
the magnetic base to be transferred from one pedestal to another
pedestal very carefully so there is no disturbance to the height of the
micrometer. All the necessary care are to be taken during this
measurement i.e. there should not be any air bubble in the polythene
pipe and the polythene pipe should be kept as stationary.
6.
While finalizing the catenary of the machine these measurements are
to be repeated 3-4 times in a day at different intervals to avoid any
possibility of the error.
7.
The height of the L.P. rear pedestal is the reference point for setting
the height of all other pedestal and L.P. base plates. The L.P. rear
pedestal height is to be first made with the benchmark plate as per
the center line of the machine with the help of water level jar.
8.
The benchmark plate is to be preserved for all future references.
9.
The catenary is to be counter checked after grouting all the
pedestals as well as after final alignment of the rotors. The final value
of the catenary may be worked out as center of the shaft on each
pedestal bore after taking the final seal bore readings. The final
catenary should match with the design value of the catenary
otherwise a necessary correction may be carried out.
10.
After ensuring the required catenary of the machine the coupling
alignments are to be made as parallel coupling.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0804G
Page No. 79of 40

80. STEAM TURBINE
500 MW
ERECTION
CRITICAL ACTIVITIES
(CATENARY AND ALIGNMENTS)
11.
The value of the catenary given over the drawing are theoretical value
calculated by the designers but due to the human error in site
measurements some time the correct coupling alignment are not
achieved then an alternate method for checking of catenary may
also be used i.e. optical measurement method or a method by which
direct journal heights are taken on each bearing in place of pedestal
height.
12.
For measurements of direct journal height a special fixture is to be
fabricated and necessary information about it can be separately given
by PS-TS if such necessity arises.
HORN DROP TEST
General description
By horn drop test the loading of the casing on each corner is determined. The horn
drop test is repeated at various stages in individual casing i.e. first without connection
of any pipe lines the horn drop readings are recorded then it is compared after welding
of inlet, outlet and extraction pipe lines etc. The horn drop readings are very important
in HP & IP casing. First the proper horn drop readings are made without connection
of any pipe lines and then the reading are taken after welding of all pipe lines on HP
& IP casing. As such the influence of these major pipe lines are notices on each
corner of HP/IP casing by comparing the horn drop test readings. The horn drop test
will indicate the quality of work during assembly/welding of pipe lines with the HP & IP
casing.
This is a very important check and may cause serious problem in operation of the
machine like high vibration in the machine failure of barring gear in hot/cold machine,
obstruction during expansion of machine etc. In horn drop test a drop is measured on
an individual corner of the casing with the help of a dial indicator by removing the
support of individual corner and then it is compared with the opposite corner. As such
this gives an indication of indifferent loading of the casing. In Russian design machine
the value of direct dynoxmetre loadings are recorded in place of this horn drop test.
Bharat Heavy Electricals Limited
Rev 00, 7-98
T1-08-0804G
Page No. 80of 40

81. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(HORN DROP TEST)
ERECTION
1.
Procedure
2.
After placement of HP and IP casing on four temporary packers
ensure that the each corner of the casing is loaded on temporary
packer and if necessary the shims may be given on packer for loading
of the casing. The load of shaft is also taken on transport device
during this stage.
3.
After transferring the load of the rotor on bearing and ensuring the
casing centering with respect to shaft the horn drop check may be
carried out.
4.
Before taking the horn drop reading ensure that the enough
clearance is available on front & rear portion of the shaft with their
seals in the casing inside. After completing the centering of the
casing the some may be lifted by 0. 20 mm on all four corners by
providing shims. This will help in avoiding the touching of seals with
the rotor during the horn drop test readings.
5.
No adjustment on packer of the HP front and HP rear pedestals are
to be carried out after taking the horn drop test of the casing In
case if any adjustment is carried out on these pedestal packers then
horn drop test are to be repeated again.
6.
No piping may be connected to HP & IP casing till initial horn drop
readings are over. The piping work should not be postponed for
want of horn drop the only thing the last joint with HP/IP casing may
be left free till completion of horn drop check.
7.
While recording the horn drop readings the casing must be
absolutely free and even the radial and axial key of front and rear
portion of the casing are either to be removed fully or these are to be
made completely free by removing their shims etc. Actually during
this stage of erection only temporary axial and radial keys are fitted
in the casing and even they carry some shims also. Before making
the casings free on axial and radial key portion the dial gauges are
to be installed to monitor the movement of the casing on radial
and axial direction. Immediately after the completion of the horn
drop test these keys/shims may be installed back and centering of
casing may be rechecked before further works.
8.
In HP casing the initial horn drop test may be done even after fitting
of breach nut assembly and HP exhaust elbow of both sides.
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0806G
Page No. 81of 40

82. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(HORN DROP TEST)
ERECTION
9.
In IP casing the initial horn drop test may also be done after fitting
of IP inlet pipe lower half assembly but this pipe of upper half
casing should not be fitted till completion of the horn drop test.
10.
All the four Jacking screw and hydraulic jack on each corner of
the casing are to be installed for the horn drop test readings. A dial
indicator is also to be installed on each corner of the casing for
measuring the drop of the casing.
11.
After initial centering of the casing the each corner packer may
be fitted with a shim of about 1 mm. for further adjustment during
the horn drop test.
12.
During the horn drop test the individual packer of the casing is
removed and the load of that corner is supported over the jacking
screw of the casing. Now gradually the jacking screw is also relieved
with the help of hydraulic jack on that corner and drop reading is
recorded. This is repeated for each corner of the casing. In case of
variation in left and right side reading the drop is adjusted by +
adjustment of shims from left to right side or vise-versa. No
subtraction / addition in shim sizes from outside is done here and
only the shims are adjusted from left to right or vise versa till equal
loading are achieved in left/right side of individual casing. The sizes
of these casing packers are recorded after completion of horn drop
to avoid any confusion at a later date while fitting the final packers.
13.
While recording the horn drop readings the drop on each
individual corner may be controlled with the help of Jacking screw
so that during this test the casing is not touching with the shaft in
gland portion of the seals at all and enough clearance is left there to
avoid damage to the seals inside the casing.
14.
During the initial horn drop the best reading within 0.05/0.06 may
be achieved by fine adjustment of the packer shims. The
comparison in horn drop value should always be made in left and
right side only of an individual casing.
15.
In case of HP casing the drop on rear end is so high that unless
the casing is locked on diagonally opposite end the horn drop check is
not possible. Therefore while recording drop on HP rear end the
front end of the casing diagonally opposite to it should be locked
with casing clamp. The pedestal is also required to be locked on all
four side with its sole plate with the help of the clamps. In case of IP
casing no locking of any corner of the casing is necessary during the
horn drop test.
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0806G
Page No. 82of 40

83. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(HORN DROP TEST)
ERECTION
16.
The final packers on HP & Ip casing are installed only after
completing the rolling test of these casing., The horn drop reading
for an individual casing may be recorded after the fixing of final
packers also. If necessary a fine adjustment may be carried out at
this stage to achieve correct value of the horn drop reading.
17.
After completing the welding of all pipe lines with the casing , the
horn drop readings are repeated again for comparison with the
earlier readings. These readings are taken along with its radial and
axial keys of the casing.
18.
During this stage exactly this can not be defined that how much
variation is permitted on these values of horn drop readings., But
this variation will indicate the influence of the piping load on the
HP/IP casing caused due to welding/connection of various pipe lines
with the casing. The variation in horn drop readings are permitted
as long as sufficient positive loading is there on each corner of the
casing. But if any corner of the casing is fully
unloaded/heavily loaded then there is no choice left and pipe lines
are to be corrected by dismantling it and making again a free joint
with the casing.
19.
During variation of horn drop reading no correction is to be made
on casing packers by adjustment of shims etc. The variation at this
stage is caused due to the piping pull/push only so if any correction
is required then the same may be carried out in piping joints and
support etc. And any adjustment in piping supports can be carried
out only after disconnecting the pipe line with the casing. Even
some time it is necessary to cut the individual or more piping joint
for correction of horn drop readings.
20.
The variation in horn drop reading of left and right side of a casing
may be permitted upto a difference of 50%.
21.
The horn drop readings are not taken for L.P. inner outer casing due
to its fabricated structure and the parting plane of the casing are
leveled on four corner with the help of water level jar arrangements.
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0806G
Page No. 83of 40

84. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(SWING CHECK)
ERECTION
SWING CHECK
GENERAL DESCRIPTION
The swing check is the measurement of radial throw caused due to coupling
face geometric form of the two rotor coupled together. This is measured on opposite
end of the coupling and at the free end of the rotor. The higher swing check value
may cause higher shaft vibration, higher bearing shell temperature etc. The value of
swing check depends on axial runout of coupling faces, the diameter of the coupling
and the length of the rotor. During the machining of rotors in the works some
tolerances are permitted by Designer's on the coupling faces of the rotor resulting to
some swing check values. The maximum swing check values permitted caused
due to the above tolerance for different diameter and length of the rotor can be
worked out from the enclosed graph. However it is recommended to keep the
minimum swing check values for better results during operation of the machine.
In a multi rotor Turbine-Generator system it is essential to measure the swing check
value in both extreme end and where the weight of the rotors are light. For example
200/210 M.W. KWU machine with Russian Generator and static excitation system
the swing check values are measured on HP rotor front end only. In 500 M.W.
machine the swing check values are measured in H.P. front end and on exciter rear
end. After having general experience of number of 200 MW & 500 MW units, a
necessity is felt to measure swing check value on IP rotor front end also for better
results during operation of the units. This can be done initially during erection with
temporary coupling bolts on LP-IP coupling before reaming/honing of coupling. Any
variation in swing check values may be corrected without any hesitation during
erection of machine. Any compromise at erection stage may cause serious problem
during operation of the unit and any correction becomes much more tedious a later
stage. The correction may be carried out either by interchanging the coupling
position or by correcting the coupling faces by scrapping/cutting in consultation
of Designers.
PROCEDURE
1.
Before placement of Module/Rotor in position the coupling faces of
all the rotors are to be measured for concavity/convexity of their
coupling faces. This can be checked with the help of a thin
rectangular light weight straight edge. No convexity is permitted on
these coupling faces however a concavity of about 0.03/0.04 mm is
permitted. In case of any variation the matter may be referred to
manufacturing units.
2.
After placement of individual Module/Rotor the coupling faces
are to be measured for axial runout before taking up alignment of
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0806G
Page No. 84of 40

85. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(SWING CHECK)
ERECTION
various rotors. The HP rotor rear coupling face can be measured
after placing it on both of its bearing. The IP rotor faces are to be
measured after placing IP rear end on bearing and front end on
lifting tackle. Similarly L.P. rotor, may be placed on bearing on its
rear end and front end supported on lifting tackle. Any variation on
axial runout on coupling faces for more then the 0.02 mm. may be
referred to Designer's before taking up further works.
3.
After completing final alignment of various rotor they are to
be coupled with temporary bolts, considering their axial
runout/geometric form of the coupling faces.
4.
During coupling with temporary bolts the higher plane of one of
the rotor face is to be coupled with lower plane of another coupling
face of the rotor.
5.
During coupling on temporary bolts the uniform tightening on all the
four temporary bolts are to be ensured otherwise it will disturb the
swing check value of the rotor.
6.
First IP-LP coupling is to be made with temporary bolts and swing
check on IP rotor front end is recorded. After this only HP-IP rotor
is to be coupled with temporary bolts and the swing check value on
HP front rotor is recorded.
7.
During swing check of IP rotor its front end is to be supported
on lifting tackle without making any connection between HP-IP
rotor.
8.
While recording swing check of HP rotor the front end of the rotor is
to be supported on lifting tackle.
9.
During swing check the lifting tackle are to be fitted properly. The
tie rod of lifting tackle should be ensured for correct fitting of its
spherical bearing and Molykote should be applied on these spherical
bearing for their free movement. These spherical bearing should
not obstruct the movement of shaft radially during checking of its
swing check value.
10.
After taking the load of the rotor on lifting tackle ensure that the
rotor is not disturb radially due to fitting of lifting tackle.
11.
During checking of swing check measure radial movement of rotor
on parting plane and rotate the rotor either on jacking oil with hand
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0806G
Page No. 85of 40

86. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(SWING CHECK)
ERECTION
barring or with the help of E.O.T crane with thick oil on bearings.
Avoid jerk during rotation of rotor while recording the swing check
values.
12.
After ensuring the swing check values as per the graph with on
temporary coupling bolts, the HP-IP and LP-IP coupling may be
cleared for reaming / honing of the coupling holes. Any variation
need correction of the coupling before reaming/honing of the holes.
13.
The final swing check value of HP front rotor is to be recorded after
fitting/ elongation of all the coupling bolts of HP-IP & LP-IP rotors.
Any variation in readings may be referred to the Designer's. For
improvement of the swing check values, the indifferent tightening
and non-sequential
14.
During checking of swing check readings, the initial few rotations are
to be given to the rotor to avoid initial sag and then only the readings
are to be recorded.
15.
Similar method is to be adopted while checking the swing check
value of the exciter except the rotor is hanged on the suitable size of
sling in place of the lifting tackle.
16.
While recording the swing check initially with temporary bolts for
HP & IP rotor, the fitting of eight number temporary bolts are
preferred in place of four bolts on the coupling.
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0806G
Page No. 86of 40

87. STEAM TURBINE
500 MW
CRITICAL ACTIVITIES
(SWING CHECK)
ERECTION
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0806G
Page No. 87of 40

88. STEAM TURBINE
500 MW
ERECTION
CRITICAL ACTIVITIES
(COUPLINGS & ALIGNMENTS
OF ROTORS)
COUPLINGS & ALIGNMENTS OF ROTORS
GENERAL DESCRIPTION
The coupling on turbine shaft are generally rigid coupling but in case of L.P. rotor
sometime the coupling head are shrunk fit and remachined. The basic function of any
coupling is to connect two or more shaft together to form a shaft assembly. The number
of shaft mainly depend upon the rating of the machine.
A very high accuracy is required during manufacturing of these rotor shaft at
works. The axial runout on the coupling face may not exceed 0.02 mm. and an
additional check is also made at works/site to ensure that the geometry of the entire
coupling surface does not deviate by more then the 0.02 mm. except the concavity on
the coupling face which is permitted upto 0.03/0.04 mm.
The radial and axial alignment of the various shafts are to be completed before their
coupling and alignments are to be done in such a way that the entire shaft
assembly follow the continuous deflection curve given over the drgs. for a particular
machine. The coupling checks determines both the radial and axial position of the
two adjacent coupling flanges relative to one another. The radial measurement are
performed on the circumference of the couplings and the axial measurement are
performed on outer most diameter of the coupling. During coupling of the two shafts
it should be ensured that the no stresses are exerted as a results of the coupling
each other shaft.
After completion of the alignment and coupling of the shaft the casings are aligned
radially and axially. Here equal importance is given to the radial & axial alignment of
stationary parts to avoid any rubbing during operation of the machine due to expansion
of stationary and rotary parts.
During the alignment of two coupling both are to be turned in same direction and by
the same amount when the measurement are taken to avoid the influence of the axial
& radial runout present in the shaft caused due to the machining.
PROCEDURE
1.
Before placement of module/rotor in position check and record the
coupling hole and journal dia of the shaft.
2.
Check coupling faces for the concavity/convexity with the
help of a thin rectangular straight edge before placement of
module/rotor in position.
3.
Check spigot and recess of the coupling and ensure their fitting
before placement in position.
4.
Place the module/rotor in position and check the radial runout of
journal and axial runout of the coupling faces independently of
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0807G
Page No. 88of 40

89. STEAM TURBINE
500 MW
ERECTION
CRITICAL ACTIVITIES
(COUPLINGS & ALIGNMENTS
OF ROTORS)
each shaft. During checking of radial and axial runout of the shaft
place H.P. rotor on both of its bearing and IP/LP rotor one end
on its bearing and another end on the lifting tackle. The radial and
axial face runout on the shaft should be within 0.02 mm accuracy.
Any variation may not be permitted here and matter may be
referred to the designer's.
5.
The HP,IP & LP rotor are aligned together and then their couplings
are made. After fully completion of HP/IP & IP/LP coupling with
tightening of their final bolts the complete shaft is cleared for
Generator rotor alignment.
6.
During initial alignment of HP/IP & IP/LP rotor the radial checks
are generally done with the help of depth micrometer and axial
gap are measured with the slip gauges. After completion of the
radial alignment the rotor are inserted in their spigot even with some
minor variation in their axial gap values.
7.
During final alignment only the axial gap values are checked at 90o
on four places by rotating both the rotor together and average of
these four reading are taken. The radial alignment reading along
with axial gaps are necessary wherever the effective spigot are not
existing in two couplings i.e. in case of LP - Gen coupling the radial
dial reading are also taken.
8.
Avoid rotation of two shaft in their spigot. If necessary these may
be rotated after taking out from their spigot.
9.
During alignment of shafts the adjustment of shims in bearing torus
may be fully avoided. The margin of + 0.30 mm. in height & left/right
direction may be kept for emergency works only. Any adjustment
during erection and normal overhauling may be done by adjusting
shims between spherical/cylindrical seat and pedestal base only. For
left and right adjustment the complete H.P. front and HP rear
pedestal may be moved with the help of their radial keys.
10.
The final packers of the pedestal and base plates are fitted before the
grouting of the pedestal itself and here no adjustment is necessary
during erection of the machine. But during overhauling of the
machine the adjustment may be carried out in these packers for
correction of catenary of the machine.
11.
During alignment of rotor make HP/IP and IP/LP coupling gap
parallel. After completion of final alignment no adjustment of
packers and keys etc are permitted on pedestals and bearing the
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0807G
Page No. 89of 40

90. STEAM TURBINE
500 MW
ERECTION
CRITICAL ACTIVITIES
(COUPLINGS & ALIGNMENTS
OF ROTORS)
final alignment of HP/IP & IP/LP rotors should be checked after
fitting of all the final keys and packers of the pedestals.
12.
After alignment couple the HP-IP & IP-LP rotors on temporary
bolts. Record coupled runout of the rotor and ensure that the
coupled runout is not more then 0.03 mm. in any where in the
journal as well as in coupling area. Before coupling of rotor on
temporary bolts record their spigot clearances by actually moving
the rotor radially.
13.
During erection IP-LP swing check on IP front and HP-IP swing
check on HP front are to be recorded on temporary bolts. These
reading are to be ensured within the design limit.
14.
Before alignment/coupling position the two shaft adjustment to each
other depending upon the higher and lower point of the shaft with
respect to their axial face measurement values.
15.
The HP-IP & IP-IP coupling may be cleared for reaming/honing
after ensuring the runout and swing check values of the rotors. In
case of variation the cause of the error may be identified and
corrected before further work of reaming and honing of the
coupling.
16.
During coupling of rotors two taper pins may be used for proper
alignment of coupling holes so that there is minimum
enlargement of holes are done at site during reaming/honing.
Unnecessary enlargement of holes may be fully avoided during
reaming/honing at site as this may cause serious problem at a later
date during overhauling of the unit.
17.
As for as possible ream/hone all the coupling bolts holes to
same size. In exceptional cases only the variation in hole sizes
are permitted. Each hole during honing should be checked for
bananas shape with the help of a parallel ground straight pin of
0.02/0.03 undersize. No banana shape is permitted in any of the
hole. The hole should be made to 0.005 mm accuracy.
18.
All the coupling bolts are to be machined and ground by 0.02/0.03
mm undersize then the hole dia. These bolts are to be fitted with
thumb pressure only and no additional force is recommended while
fitting these bolts.
19.
A very thin layer of molykote may be applied on all the coupling
bolts during their fitting. The molykote should not be applied on
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0807G
Page No. 90of 40

91. STEAM TURBINE
500 MW
ERECTION
CRITICAL ACTIVITIES
(COUPLINGS & ALIGNMENTS
OF ROTORS)
seating face of the coupling bolts. This may cause in breaking of
their locking pin during elongation of coupling bolts.
20.
All the coupling bolts are to be balanced before finally
fitting/tightening in position. These are to be balanced within an
accuracy of 5 gms each along with their nuts. In case all these bolts
are of equal size then their weight must be equal. In exceptional
cases the 180o opposite bolts may be made of equal weight.
21.
During tightening of coupling at any stage first tighten four bolts on
90o location. Always tighten bolts in proper sequence with
180o opposite bolts. These bolts are to be elongated to the value
given over drgs.
22.
During tightening of coupling the radial runout on journal and
coupling may be checked at various stages during tightening of
bolts. The final coupled runout should not be more then 0.03 mm. on
coupling and journal of the shaft.
23.
After final tightening of LP-IP and HP-IP coupling the swing check
value on HP front rotor is to be rechecked. In case of variation in
value a proper correction is to be made with consultation of
designer's. The indifferent or unsequential tightening for achieving
the swing check value or coupled runout value may be fully avoided.
this may cause unnecessary stresses on the coupling.
24.
After completing the coupling work the casing radial and axial
alignment may be done.
Bharat Heavy Electricals Limited
Rev 00,
7-98
T1-08-0807G
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92. STEAM TURBINE
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ERECTION
Welding of steam inlet and exhaust pipe lines with HP and IP
casing
In 210 MW machine the HP Turbine is supplied with two inlet and two exhaust flanges
for connection of the pipe line.but in case of 500/250 MW HP Turbine the casing is
supplied with four inlet flanges also. As such in 200 MW machines, only two ESV
control valves are used in the system. Whereas in 500/250 MW machines , It may be
either two ESV oontrol valves or four ESV control valves to cope with the design of the
casing.
Similarly in 210 MW machines, the I.P. casing is supplied with two inlet flanges and
eight number exhaust branches or either two exhaust branches only along with two inlet
flanges. These eight number exhaust branches are distributed four on each side of the
casing and each four branches are joined together with one common pipe while
connected to L.P. casing. The 500 MW I.P. casing is similar to the 210 MW I.P. casing
but some time these are supplied with four numbers of I.V. control valves also. The
inlet lines from each two control valves are joined together and make one connection
with the I.P. casing in bottom. As such in 210 MW machines, only two I.V. control
valves are used but in case of 500 MW machines, there can be either two I.V. control
valves or four I.V. control valves.
After completion of the rolling test the installation of final keys and packers of the H.P.
and I.P. casing, the same can be cleared for welding of inlet and outlet pipelines. The
main steam inlet line from main steam strainer to the control valves and then from
control valves to the H.P. casing need much more care during erection / welding of the
pipelines. Similarly the Hot Reheat lines between two Hot Reheat strainer to the control
valves and from control valves to the I.P. casing also need equal care during erection /
welding of these pipelines. These pipelines are directly affecting the performance of the
turbine during operation of the machine and a necessity is felt to fully involve the turbine
Erection Engineer in erection / welding of the pipelines at site along with the Piping
Engineers. The piping connection between I.P. casing to L.P. casing i.e. cross around
piping also need proper care but due to its construction with number of bellows in the
system. Present method of erection / welding much of the problems are not faced
during operation of the machine. However if proper care is not taken here then that
may cause the unnecessary loading on the various bellows of the piping and reduction
in their life. In case, if proper care is not taken during erection / welding of MS inlet,
CRH & HRH connections with HP & IP casing, a load will be transfer from the pipe line
to the casing. Which may cause vibration in the machine, obstruction in expansion of
the machine, obstruction of barring gaer operation in hot / cold machine, higher babbit
metal temperature and failure of brg. babbit etc. during operation of the machine.
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Rev 00,
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93. STEAM TURBINE
500 MW
ERECTION
PROCEDURE
The following points are to be taken care while welding MS, CRH, HRH pipelines
with HP & IP casing and control valves / strainers.
1.
The HP & IP casings are to be cleared in all respects after fitting of
final packers and axial / radial keys of the casing.
2.
The ESV & IV valves are to be cleared after fitting of their
servomotors and then levelling including the correct elevation etc.
3.
The equivalent insulation weight is to be given on each control valve
befor connection of any pipeline with the valve. The change in hanger
value of the control valve is to be adjusted back by lifting the valve
with the help of hangers. The control valve hanger reading should
remain same as before and after installation of equivalent insulation
weight on the valve. After this all the three hangers of each valve are
to be locked to avoid any movement of the valve in upward direction,
in case the equivalent insulation weight is removed or any of the
servomotor is removed. Before starting of any welding with the
control valve the valves are to be locked for their movement.
4.
Erection and welding of MS line upto MS strainer and HRH strainer
are to be completed first including either their insulation or
equivalent weight is to be given for their insulation weight in the lines.
These lines should be in perfect floating condition on their hangers
before taking up the further work of MS & HRH lines upto the ESV
& IV control valves.
5.
Install MS & HRH lines between strainer and control valves and weld
all the inbetween joins of the pipelines except the end joints with the
valves and strainers. These lines are to be erected in such a way that
both the end joints remain free and parallel with the strainer and
control valve after taking their load on hangers. The freeness of
joints are to be ensured after giving the equivalent insulation weight
of the lines.
6.
Weld MS & HRH lines with the strainers and again ensure the
freeness / paralalllity of MS & HRH lines with the ESV and IV
control valves. Any minor variation may be readjusted on hangers to
obtain the freeness of the joints with the control valve.
7.
Install the MS and HRH lines between control valves and HP /IP
casing . Now all the in between joints may be keeping the end joints
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94. STEAM TURBINE
500 MW
ERECTION
free with the valve and the casing. The erection of these lines are to
be done in such a way that freeness and parallelity of end joints are
achieved after fully floating the pipe lines on their hangers. The
equivalent insulation weights are also to be added during erection of
these pipe lines before welding the end joints.
8.
After ensuring the freeness and parallelity of the end joints between
ESV control valve and HP casing , the same may be welded together.
But the stress relieving of all the in -between joints of the lines are to
be completed before taking up work of the above last two end joints .
Similar proceedure may be followed for the lines between I V valves
and IP casing also.
9.
Weld left and right MS and HRH joints togethers with the HP and IP
casing to avoid any left and right loading on the casing . during
welding the left and right movements of casing may be monitored by
installing the radial dial gauge on the casing.
10.
The CRH lines are to be erected on their permanent hangers and the
joint with the HP casing are to be made free /parallel after floating
the pipe lines. The left and right side casing joints are to be welded
together , similar to MS lines but before weling of these line the inbetween joints are to be completed first . The equvalent insulation
weight is also to be given on these line while checking the freeness of
end joints with the HP casing.
11.
The horn drop readings are to be recorded for both HP and IP casing
after copletion of the job including insulation of pipe lines and
control valve etc.
SPECIAL CARE
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Rev 00,
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95. STEAM TURBINE
500 MW
ERECTION
1.
If possible keep the insulation weight and servomotors on ESV and I
V control valves during erection /welding of these MS & HRH lines
from strainers to the valve and casing . If the above condition are
fulfilled then there no need of any locking of the valves during the
welding of any pipe lines.
2.
The control valves hanger readings are to be measured with the inside
micrometer in various stages and changes are to be monitored
properly . The readings are to be measured in the following stages :− After complete leveling of ESV and IV control valves with their
servomotors
− After putting the equivalent insulation weight on the control
valves.
− After readjustements of control valve height equivalent to
insulation weight.
− After connection of MS &HRH lines with the strainers .
− After connection of MS & HRH lines with the HP & IP casing .
− After complete insulation of control valve and pipings.
3.
Ensure proper clraning of MS and HRH lines between controls valve
and casing as these lines are not covered in steam blowing operation .
Proper care is to be taken during erection of these lines to avoid entry
of foreign material.
4.
The steam blowing of the MS and HRH pipe line are to be carried out
after fully completing the erection /welding of lines from control valve
to the HP and IP casing .
5.
All the four corners of the casing may be locked with the casing clamp
during welding of piping joints to avoid movement of casing radially.
6.
The load of the upper half HRH pipe upto the flange supplied by
turbine supplier is taken by the IP casing and by the piping hangers.
This may be taken care while erecting the HRH lines.
Bharat Heavy Electricals Limited
Rev 00,
7-98

96. STEAM TURBINE
500 MW
ERECTION
SPRING LOADED FOUNDATION
The spring support for TG foundation in our country is a new development though some
of the machines are already in operation with spring loaded foundation at various power
stations. Most of TG foundation built in Germany in last 20 years are spring loaded
foundation. The various machines in operation with BHEL supplied equipment and
spring loaded foundations are Dadri 4x210 MW , Trombay 1x500 MW, Dahanu 2 x 250
MW. Similarly the machines which are going to come with spring loaded foundation
with BHEL equipment are Chandrapur 1 x 500 MW , Suratgarh 2x250 MW , Unchahar
2x210 MW and Vindhyachal 2x500 MW.
The spring units for all the above TG foundations are supplied by M/s GERB which they
call the GERB vibration isolation system for TG foundation.
In BHEL , we have yet to satisfy fully ourselves about the advantages of this system
after getting the feed back from various machines under operations with spring loaded
foundation though the advantage claimed by M/S GERB are listed below:
1.0 REDUCTION IN BASE MAT SITE AND ITS COST :
The vibration to the main column are isolated by the spring element resulting to small
size base mat which reduces the construction cost and time.
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97. STEAM TURBINE
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ERECTION
2.0 REDUCTION IN NUMBER OF COLUMNS:
The same column of TG deck may also be used to support surrounding floors at the
building , so that the total number of columns are reduced and the space to
accommodate more equipment is increased. This results in more rigidity of building
structure of surrounding floors and further in cost saving.
3.0 EASY HANDLING OF SETTLEMENT PROBLEMS:
Excessive settlement of column can easily be adjusted by inserting or removing shims
in spring units.
4.0 SUBSEQUENT TUNING OF THE FOUNDATION :
It is possible to tune the foundation subsequently by replacing the spring elements
having different load capacity of the springs.
5.0 EARTHQUAKE PROTECTION :
Machine will have more steadiness and stability in the event of earthquake compared to
normal foundations.
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98. STEAM TURBINE
500 MW
ERECTION
INSTALLATION OF SPRING ELEMENT:
The spring element in 500MW machines and further higher rating machines are used
with visco dampers. The springs units are not supplied to site with required pre-tension
values through these are supplied with some amount of pre-tension. The required pretension of the spring units are done at site before its installation in position. A special
device for pre-compression of these springs units is also supplied by spring supplier.
The shuttering of RCC slab of TG deck is furnished before installation of these spring
units. The top surface of individual column where these spring units are mounted
should be within accuracy of +00 mm to -3.00 mm. If necessary these may be
corrected by chipping before installations of the spring units. The level deviation among
various columns is permitted +00 mm to -5.00 mm in total including individual column
variation of +00 mm to -3.00 mm.
The bottom shuttering of pedestal must be cut over the column head for lowering the
spring units. After lowering the spring unit the cover steel plates are placed in position
with shuttering supports. An air gap of about 5.00 mm to 10.00 mm is left between
cover plate and spring units for settlement of deck during casting. The visco dampers
are also filled up at site only with visco liquids supplied by spring supplier. The filling
procedure of visco liquid is explained separately by the spring supplier.
Each spring units are placed over the resistance pad to avoid movement of the spring
units during operation of the machine. Similarly the resistance pad is given on top of
the steel shim to avoid the shifting of the shim during operation of the machine. Each
spring unit is provided with 10.00 mm of steel shim for future adjustment.
The spring units are not only pre-compressed for dead load of the machine but it is
further pre-compressed to prevent the loosening of the spring during installation of the
equipment due to unforeseen additional loads. If major variation in calculation of load
over the spring units are not expected then an additional compression of 5.00 mm is
sufficient for this purpose. During installation of spring units, additional shims are
provided for this 5.00 mm additional compression and which are removed at the time of
loosening of the spring elements before final alignment of the machine. These
additional shim are removed in minimum two stages after ensuring, that all the major
parts of the machine are installed and condenser have been filled upto operating water
level including CW pumps in operation for full load condition of the machine. It is also
not necessary to remove this complete 5.00 mm shims from each spring unit and the
same may vary from spring unit to spring unit depending upon the variation of column
level/elevation and variation in level of spring cover plate etc. Refer section “Releasing
of TG Deck Spring” for removal of additional shims.
Bharat Heavy Electricals Limited
Rev 00,
7-98

99. STEAM TURBINE
500 MW
ERECTION
RELEASING OF TG DECK SPRING
The TG deck springs are released after installation of all Turbine Generator
components including piping and the condenser has to be filled up to operating level
including CW pump in operation for full load condition. The shims provided for
additional compression of the spring units are also adjusted during this stage, the final
alignment of various rotors and turbine casing are done after release of the spring unit.
The Generator hydrogen cooler & LP heater if any inside the condenser are to be filled
up in cooling water space for their operating condition before release of TG desk spring.
The insulation of various casing / pipe lines including cladding if any are also to be
installed otherwise the equivalent weight is to be incorporated before release of desk
spring. All the pipe lines connected with the Turbine and Generator should be made
available on permanent hangers and supports to avoid any additional load on the TG
deck afterwards. The TG deck should also be made free all- around to avoid any
obstruction in its movement.
Many time it is not possible to wait till completion of all the works on Turbine Generator
area as required for final alignment of all the rotors for reaming / honing of the various
coupling. In such cases without releasing of the spring units the alignment of all the
rotors can be done and reaming / honing including fitting of all final coupling bolts can
be completed. The coupling bolts need not be elongated at this stage and once all
other works are ready for final alignment of rotors ,the coupling may be opened and
realigned. After realignment , the coupling bolts are to be fitted without any further
reaming / honing of the coupling holes. The radial alignment of HP, IP and LP casing
i.e. rolling test of all these casing are also to be carried out after final alignment of rotor
and with the CWP in operation etc. i.e. with similar conditions of final alignment of
rotors.
During release of TG deck springs and final alignment of rotors the condenser spring is
also to be kept in floating condition considering that condenser neck welding is already
done. Similarly the condenser spring measurement should be with in + 1.00 mm
otherwise the shims may be adjusted in condenser springs. No adjustment of TG deck
springs or condenser springs are permitted after final alignment of the rotors. During
any subsequent adjustment of TG deck spring the final alignment of all rotors are to be
checked.
After placement of TG deck springs in locked condition with shims and resistance pad
etc, an equal air gap between 5 .00 to 10.00 mm is left between all the springs and
bottom of the steel cover plate. The exact value of air gap can be determined by the
civil engineer depending upon his experience but generally it is between 5.00 to 10.00
mm only. The form work and support of TG deck are removed once the concrete has
hardened sufficiently. This is generally done after 28 days of casting of the deck and
all load of deck is transferred over the spring units . Afterwards TG pedestals are
placed /aligned and their elevation are maintained as per required catenary of the
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Rev 00,
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100. STEAM TURBINE
500 MW
ERECTION
machine before grouting the pedestals with the non-shrinking cements . During
releasing of TG deck spring while this additional 5.00 mm shims (for additional
compression) are removed the catenary of the machine is to be achieved within + 0.20
mm bearing No. 1&4 with the help of TG deck springs by adjusting the shims and
afterwards only the rotors alignments should be taken up. Any minor variation in
catenary left after releasing of TG deck spring may be adjusted in the
spherical/cylindrical seat of the bearings for achieving the correct alignment of the
shaft.
The height of TG deck spring are taken on four corners near the springs. Here some
punch mark may be provided on all springs so that measurements are taken at the
same place always. Certain minor variations on height of the spring units are permitted
, if it is required for achieving the Catenary of the machine. The TG deck spring shims
are adjusted with the help of hydraulic jacks. Either two/four numbers hydraulic jacks
are used for this purpose which are supplied by the spring supplier. Similar methods
are used for release of the spring locking bolts also. These hydraulic jacks are group
operated type and works with one pumping unit which is electrically operated. The
ready-made galvanized shims are also supplied in required sizes alongwith spring unit
in 3.00 mm and 2.00 mm thickness so an adjustment of upto 1.00 mm is possible in
spring Units.
After finally release of TG deck spring and with water in condenser hotwell upto
operating level including CWP in operation then spring heights are measured on four
corners for all future reference. The sizes of the shims are also recorded for each
spring. A bench mark may also be preserved on TG floor as reference for LP rear
pedestal parting plane height for all future reference. During realignment of machine in
subsequent overhauling the `catenary of the machine are to be checked and if
necessary the shims of the springs are to be adjusted to achieve the correct catenary or
at least to the old values . The catenary checking and alignment of rotors may be done
together but all major adjustment for correction of catenary is to be done by adjusting
the shims of the spring units. Any minor adjustment for alignment may be done on
bearing if it is in permissible values and margins is available on the bearings seals
bores.
Bharat Heavy Electricals Limited
Rev 00,
7-98

101. STEAM TURBINE
500 MW
ERECTION
CONDENSER NECK WELDING IN SPRING LOADED
FOUNDATION OF 200/250/500 MW KWU
DESIGN MACHINE.
Before neck welding all the major components of the condenser are to be installed
including its tubing , water boxes, dome wall assembly and its stiffener pipe, etc. After
installation of all the major components of the condenser the spring are released i.e.
condenser is floated for welding with the Turbine.
After floating the condenser, the spring height is recorded on its four corner and further
they are pre-compressed for the value of welding shrinkage’s by an amount of 3.00 mm
depending upon the designer requirements. The required pre-compression of the
condenser spring can be done by filling the equivalent weight of the water in the hot well
of condenser and then locking the condenser spring at that position. The locking of
springs can be avoided if water is filled up to required level and level is maintained
during neck welding of the condenser. Sometime during floating of condenser an
additional weight of water is filled up in condenser depending upon the designer’s
requirement.
The TG deck springs are kept in locked condition during the neck welding of the
condenser. After completing the neck welding and draining of condenser ( for
equivalent value of the pre-compression of the condenser springs) the condenser
springs height are recorded and if variation are noticed for more than +/- 1.00 mm than
the necessary adjustment is to be carried out. This can be done by adjusting the shims
in the springs although if proper care is taken during the neck welding no such variation
are noticed.
Further during floating of TG deck springs the condenser spring heights are also
monitored and if necessary the shims may be adjusted on condenser springs to
maintain the old values of the condenser spring at the time of floating of condenser.
During subsequent overhaul of the unit the condenser spring height alongwith TG deck
spring height need a monitoring. As a general practice whenever the TG deck spring
height are checked then the condenser springs height are also to be checked.
During floating of the condenser it is to be ensured that condenser is free all a round
and none of the pipe line are obstructing the movement of the condenser. All the
connected pipe lines of the condenser are to be ensured on permanent hangers before
floating of the condenser. The condenser neck welding is carried out as per the backstep method for which the procedure is laid down in KWU manual of steam Turbine
assembly sheet No 1-2-6330-0001/1.
During neck welding the complete height of L.P. inner and L.P. outer casing is installed
in position.
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7-98

102. STEAM TURBINE
500 MW
ERECTION
ERECTION OF PIPING
NOTE: These guidelines are intended to provide advice to lay and support
pipings at site, especially non-prefabricated pipes < Nb 50.
GENERAL
These guidelines apply to turbine and generator piping forming part of the
BHEL scope of supply and delivered to the site in the form of prefabricated
pipe sections and straight lengths of piping.
Generally Applicable Specifications
Prefabricated lines > Nb 50
In case of deviation the site erection engineer to decide in alternate
routing.
LAYING OF PIPES WITH ROUTING SPECIFIED IN PIPING PLAN.
1.
Lay the lines as specified in the piping plans.
2.
Support them at the defined points.
3.
Cold bending method and special pipe-bending equipment should be
used for bending of pipes.
4.
Care should be taken to ensure that the deformation is well within the
tolerance limits.
ACCOMMODATION OF MOVEMENT AND EXPANSION.
1.
Care is to be taken to ensure the movements at pipe terminals and
thermal expansion of the pipes themselves are
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103. STEAM TURBINE
500 MW
ERECTION
accommodated by adequately long legs and expansion loops.
2.
For lines connected to emergency stop valves (main steam valve, stop
valve, bypass valve ) allowance of ± 20 mm in all directions shall be
made.
3.
Determine with the aid of the diagram (Fig. 1 & 2 ) the pipe legs
required to accommodate terminal movement and thermal expansion.
4.
Ensure the valid coordinate system of that power plant (Fig 13) is
adhered.
5.
If it is not possible to obtain values for movement of the terminal
point taken from Fig 14, add a 50% safety margin to the thermal
expansion calculated for the connecting pipe Figs 3 & 4.
ASCENDING AND DESCENDING GRADIENTS
1.
Install all lines with the ascending or descending gradients
appropriate to their function.
2.
Lay supply lines with a constant ascending or descending gradient at least 5 mm/m - with at the very least a 5O slope (-90 mm/m).
3.
Lay drain and vent lines with a descending gradient of a least 20
mm/m.
PIPE SUPPORTS
1.
Pipe supports should not restrict pipe movements. Where springloaded supports are used, the additional load or load relief exerted by
spring force on the pipeline at maximum deflection from its unloaded
position should not exceed 25% of the supported pipe weight. (Fig. 6).
2.
The Table (Fig. 5) gives reference values for pipe supports.
3.
When fabricated pipe supports and guides, only flat steel pipe clamps
and aluminum clamps serve as the pipe bearing surface.
4.
The use of round -steel shackles should be avoided in all cases.
ATTENTION: Suspension supports are to be preferred to support
from beneath. Friction points should be avoided.
Bharat Heavy Electricals Limited
Rev 00,
7-98

104. STEAM TURBINE
500 MW
ERECTION
WELD PREPARATIONS AND WELDING OF PREFABRICATED AND
NON-PREFABRICATED PIPES.
WELD PREPARATIONS
1.
Ensure proper edge preparation as per drgs.
2.
Remove scale, rust, paint etc. from weld joints.
1.
Complete welding as per WPS/drgs.
2.
Nitrogen purging to be done wherever required.
3.
Complete N.D.T.
WELDING
Bharat Heavy Electricals Limited
Rev 00,
7-98

105. STEAM TURBINE
500 MW
ERECTION
SPECIAL SYSTEM REQUIREMENTS
Lubricating Oil System
1.
Match up, weld and examine the prefabricated connecting pieces of
the discharge and suction nozzles prior to the final erection of the first
bearing pedestal.
2.
Other matching and welding work to be done when the bearing
pedestal is full assembled.
3.
The direction of flow of the oil temperature control valve should be
ensured as indicated by markings on the valve itself.
Jacking Oil Lines
4.
Where possible, lay jacking oil lines so as to be protected by other
lines of larger nominal diameters against being used as an aid to
climbing.
5.
Once the line has been welded to the bearing pedestal, fit a protection
plate to protect the line in this area.
6.
Oil Vapor extraction lines
7.
Ensure that oil vapor extraction lines are laid with a gradient
descending constancy towards the main oil tank without low points.
A drain loop at the lower end of this line upstream from the blowers
return drains to the oil tank.
8.
Fire Prevention
9.
To avoid fire hazards, do not route oil lines near lines or components
at high temperature.
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106. STEAM TURBINE
500 MW
ERECTION
10.
If the laying of oil lines in these areas cannot be avoided, ensure that
no detachable connections or valves are erected directly above hightemperature lines or components.
Control Fluid System
Single Fluid Lines
11.
Signal fluid lines comprise all those lines in which some kind of
signal or pulse is transmitted from one point to another (in other
words, almost all fluid lines which do not lead directly from pump
via filter to component). These includes : primary oil lines,
secondary auxiliary secondary and bypass signal fluidlines, trip,
auxiliary trip, test and return fluid lines, by[pass startup fluid
lines, and water filled (condensate-filled) impulse lines.
12.
They do not include : turbine start-up and auxiliary start-up oil
lines, pilot fluid line (between pressure transducer and pilot valve
on Nb200 and Nb250 bypass stop valves with LP hydraulic
system).
13.
To ensure correct functioning of signal fluid lines, lay them with
an adequate ascending or descending gradient to prevent air
pockets from forming and accumulating. A number of different
routing strategies are available for this purpose (the control
medium flows from the control equipment) Fig. 7.
Version 1.
If a line is installed from the control equipment to the load with an
ascending gradient (ascending in the direction of flow) there must be
a minimum gradient of 67 mm Fig. 7.
Version 2.
If a line is installed from the control equipment to the load with a
descending gradient (ascending gradient counter to the direction of
flow) there must be a minimum gradient of 175 mm/m Fig. 7.
If it is not possible to install the line as shown in Version 1&2, two other
strategies may be adopted (Fig.8)
Version 3.
If local conditions make it necessary to install the line with one or more
high points, each high point must be provided with permanent venting
facilities (orifices with a diameter of 1.5mm). Fig.8.
Version 4.
If local conditions make it impossible to observe the 10OC minimum
gradient in installing a line as shown in Version-2, then reduce the
Bharat Heavy Electricals Limited
Rev 00,
7-98

107. STEAM TURBINE
500 MW
ERECTION
gradient required from 175 mm/m to 67 mm/m by introducing an
external supply to reverse the direction of flow Fig.8.
Installation of Damping Devices
14.
The as-installed configuration of each damping device is indicated in
symbolic form on the system flow chart. As the flow is generally
directed via the installed orifice plate, i.e. pressing the ball downward
against the valve seat, care must be taken to interpret the symbol
correctly.
If the system flow chart indicates that the damping device should be
installed as shown in Fig.9 the flow passes via the orifice plate (slow
flow) if the damping device is to be installed the other way around the
ball is lifted away from the seat and thus permits a rapid through flow.
SEAL STEAM SYSTEM
Seal Steam Lines, valve Stem Steam Leak-Off Lines and Seal Ring Steam LeakOff Lines.
1.
In laying these lines, provide sufficient compensation for thermal
expansion. The service temperature for all lines can be assumed to be
approximately 450OC. These pipes expand by approximately 6 mm/m
between the cold state (initial temperature 20OC) and the hot state.
ATTENTION : Always include a safety margin.
Leak-Off and Seal Steam Extraction Lines in the Steam Seal Casings.
1.
Insert leak-off and seal steam lines, though the pipe penetrations in
the LP end walls before mounting the LP bearing pedestals. Connect
the lines up when the LP steam seal casings have been fully
assembled.
2.
Ensure that the lines are concentric within the penetrations to
accommodate the insulation to be installed subsequently.
Bharat Heavy Electricals Limited
Rev 00,
7-98

108. STEAM TURBINE
500 MW
ERECTION
Pressure Sensing Line Terminals for the Seal Steam Control system
1.
Erect the pulse lines to the pressure transducers in a manner which
will prevent the generation of fluctuating pressure pulses. Refer
Fig.12.
2.
Lay the header, with an ascending gradient from the terminal point to
the pressure transducers, making sure that the pipe leg below the
transducers has a gradient of 30OC.
3.
From this pipe leg, in which two Nb 25 nozzles are welded, erect two
lines 500 mm long, to the pressure gauge cutoff valves of the pressure
transducers.
NOTE: The header should not be insulated over the last 2-3m so as to
ensure that all condensation takes place below the final connection
to the transducers. Fig.12.
DRAIN SYSTEM
Drain Lines
1.
All drain lines shall have as steep a gradient as possible, an all cases at
least 20 mm/m.
2.
In erecting these lines, provide sufficient compensation for thermal
expansion. The service temperature in plant can be assumed to be
approximately 450OC.
3.
These pipes expand by approximately 6mm/m between the cold state
(initial temperature 20 OC) and the hot state. Determine from the
diagram (Fig.2) the minimum legs required to accommodate
movement.
ATTENTION : Always include a safety margin.
4.
On drain lines made from thick-wall piping, ensure straight pipe
sections at least 500 mm long between the drain sockets (on casings
and pipes) and the first bend in the pipe.
PRESSURE SENSING LINES, GENERAL
In laying these lines, observe the following:
Bharat Heavy Electricals Limited
Rev 00,
7-98

109. STEAM TURBINE
500 MW
ERECTION
1.
Lines under pressure must be laid with a constant descending gradient.
2.
Lines under vacuum must be laid with a constant ascending gradient.
3.
The above lines must have an adequate gradient - at least 1:15 (67 mm/m) between their connection point and the transducer rack.
4.
Lay pressure sensing lines such that the primary cutoff valve forms an anchor
point, which entails laying the line between the connection point and the
primary cutoff (anchor point) with the sufficient flexibility to accommodate
movement of the connection point. A compensating leg extending 1 meter in
each of two planes should be provided in the lubricating oil, control fluid and
drains system on account of the minimal terminal movement there. (Refer Fig.
10 & 11).
Locking Devices for Threaded Connections.
5.
All Fasteners should be locked using tab washers or a suitable thread lock
adhesive.
Bharat Heavy Electricals Limited
Rev 00,
7-98

110. STEAM TURBINE
500 MW
ERECTION
DESCRIPTION OF THE COORDINATE SYSTEM
1.
When isometric are drawn of piping, an indication of the three orthogonal axes
X, Y and Z as in Fig.3 is required.
2.
Projections of these axes in the corresponding drgs. shall be as under :
X axis
= view toward generator
Y axis
= view upward generator
Z axis
= view to the right
3.
This axis designation shall be positive where no prefix is used.
4.
A minus sign prefix shall be used to indicate the opposite direction.
Bharat Heavy Electricals Limited
Rev 00,
7-98

111. STEAM TURBINE
500 MW
ERECTION
APPLICATION
This device is used during heat-tightening of cylinderjoint bolts/studs of
steam turbine to a predeterminedjoint pressure. Heating process is
carried out by sending hot oxy-acetylene gases mixed with compressed
air into the holes provided in the bolts stud. This heating causes
elongation of the studs and then the capnut of corresponding stud is
screwed down by a specified amount in hot condition to provide a
calculated joint pressure in cold condition.
SCOPE OF WORK
This specification covers the broad guide lines on design, manufacture and
supply of gas heating device for the above mentioned purpose. Scope of
supply also covers associated compressed air piping including a fine
regulating valve, pressure gauge & pipe fittings. Source for compressed
air shall be made available. Similarly oxy-acetylene cylinder with heating
torch not covered under this scope.
A measuring device for measuring the extension of stud/bolt due to heating
is also included in the scope of supply.
FUNCTIONAL REQUIREMENT AND DESIGN INFORMATION:
SPECIFIED ELONGATION OF THE STUD TO BE ACHIEVED WITHIN 15 MINUTES.
A MINIMUM CLEAR HEIGHT OF 600 MM ABOVE THE CAPNUT IS AVAILABLE
FOR INSERTION AND REMOVAL OF THE HEATING DEVICE.
SEPARATE HEATING DEVICE IS REQUIRED FOR EACH HOLE SIZE OF HEATING
HOLE IN THE STUD I.E. 20,25 AND 32.
DESIGN SHOULD ENSURE THAT VENT HOLES FOR RELEASE OF HOT GASES
IN OUTER TUBE REMAIN OPEN TO ATMOSPHERE IN ALL OPERATING
CONDITION.
MATERIAL OF ALL THE STUD IS SAME 1 1/4 CR MO 3/4 V TIB. THE 0.2 PROOF
STRENGTH IS 70 T/MM2
Thermal conductivity of above materials =
0.094 cal/cm-secoC
Specific heat
-do=
0.001 cal/kg-oC
Coefficient of linear expension =
13x10-6
OTHER REQUISITE DIMENSIONAL INFORMATION FOR EACH HEATING HOLE
SIZE IS FURNISHED BELOW.
Bharat Heavy Electricals Limited
Rev 00,
7-98

112. STEAM TURBINE
500 MW
ERECTION
ALL DIMENSIONS IN M.M.
STU
D
HOL
E
SIZE
LENGTH
OF
HEATING
HOLE
HEATING TUBE DIMENSIONS IN SIDE STUD
APPROX.
MASS OF
HEAVIEST
PIECE
LEHGTH
20
25
32
190
330
565
OD x TH
LENGTH
DIA
DIA
16 x 2.9
20 x 2.9
25 x 2.9
49
71
79
35
39.5
42
20
25
32
36
46
46
ELON
GATIO
N
5 Kg
45 KG
85 Kg
185
325
560
0.32
0.53
0.90
D3
160
230
530
STUD GAUGE
LENGTH FOR
WORKING
ELONGATION
FUNCTIONAL DESIGN
A typical outline sketches fig. No. 1 showing general arrangement of gas heating
device and fig No. 2 - measuring device are enclosed for reference purpose.
THIS HEATING DEVICE IS A PORTABLE UNIT. HEATING SHOULD BE POSSIBLE
IN ANY OF THE STUD IN ASSEMBLED CONDITION. HEATING SOURCE IS
OXY-ACETYLENE GAS.
OXY-ACETYLENE TORCH IS IGNITED OUTSIDE AND THEN IT IS INSERTED IN
THE HOLE MEANT FOR IT IN THE INLET CHAMBER. STANDARD TORCH
SIZES SHOULD BE SELECTED FROM THE INDIAN OXYGEN LTD;
CATALOGUE, SUITABLE CHAMPING DEVICE FOR HOLDING THE OXYACETYLENE TORCH DURING HEATING PROCESS SHOULD BE
PROVIDED.
Bharat Heavy Electricals Limited
Rev 00,
7-98

113. STEAM TURBINE
500 MW
ERECTION
A COMPRESSED AIR PIPING OF SUITABLE SIZE IS FIXED TO INLET CHAMBER.
COMPRESSED AIR INSCRIBES THE OXY-ACETYLENE FLAME AT THE EXIT
FROM INLET CHAMBER AND LED TO A MIXING CHAMBER.
FROM MIXING CHAMBER HOT GAS MIXTURE IS LED TO HEATING TUBE
THROUGH IS BOND.
HEATING TUBE IS HELD CO-AXILLAY IN THE STUD HOLE. END OF HEATING
TUBE KEPT AT A REASONABLE DISTANCE FROM END OF HOLE IN THE
STUD.
AFTER IMPARTING THE HEAT TO THE STUD, THIS GAS-MIXTURE TRAVERSE
BACK THROUGH ANNULUS PASSAGE BETWEEN OUTER TUBE &
HEATING TUBE & RELEASED TO ATMOSPHERE THROUGH VENT
HOLES IN THE OUTER TUBE.
A FINE REGULATING VALVE ON COMPRESSED AIR PIPE LINE IS PROVIDED TO
REGULATE THE COMPRESSED AIR PRESSURE AND DAME IS TO BE
READ ON CIRCULAR PRESSURE GAUGE WITH A RANGE 0 TO 20 ATA. A
PROPER AIR PRESSURE ENSURE THAT GAS MIXTURE REACHES HOLE
BOTTOM WITH A REASONABLE VELOCITY OF HOT GASES INTO
ATMOSPHERE FROM SAFETY CONSIDERATION.
IN ELONGATION MEASURING DEVICE INCLUDES A SIMPLE MEASURING
ROD, A SLEEVE AND A DEPTH GAUGE. READINGS ON THE DEPTH
GAUGE SHOWING LENGTH IF STUD ARE RECORDED IN COLD
CONDITION BEFORE START OF HEATING PROCESS, AND THEN AFTER
HEAT TIGHTENING AGAIN IN COLD CONDITION. THE DIFFERENCES
OF THESE READING GIVES THE ELONGATION ACHIEVED.
Bharat Heavy Electricals Limited
Rev 00,
7-98

114. STEAM TURBINE
500 MW
ERECTION
MATERIAL OF CONSTRUCTION
While selecting the material for different components of heating device due
considerations to its operation at elevated temperature, high temperature
gradient and thermal cycling to be taken into account.
It is customary to use allow steel (CR-Mo-V or CR-Mo) to provide long life to these
component.
Measuring rod, depth gauge & sleeve material should be hardened and tempered.
MECHANICAL DESIGN:
THE SOLE RESPONSIBILITY OF MECHANICAL DESIGN RESTS WITH SUPPLIER
CONSTRUCTION OF THE DEVICE SHOULD BE ROBUST TO WITHSTAND
THERMAL CYCLING AND THERMAL STRESSES. DEVICE SHOULD BE
EASY TO INSTALL ASSEMBLE AND DISSEMBLE.
DIMENSIONAL ACCURACY, FITTING AND SURFACE FINISH SHOULD BE AS PER
I.S. 2102-1962 MEDIUM, I.S. 2709-64, I.S 3073-67 RESPECTIVELY.
WELDING IF USED ANYWHERE IN ASSEMGLY SHALL BE CHECKED FOR CRACK
& DEFECTS. DEFECTS TO BE RECTIFIED.
DUE PRECAUTION TOWARD OPERATIONAL SAFETY MUST BE TAKEN.
Bharat Heavy Electricals Limited
Rev 00,
7-98

115. STEAM TURBINE
500 MW
ERECTION
Measuring Unit
1.
Measuring unit consists of sleeve, depth gauge and measuring
rod. Depth gauge should have least account of 0.05 mm. Depth gauge
should be in general as per DIN 862. Its scale must be case hardened.
2.
Measuring rod length may be made up in two pieces. Base piece is to
have a flat circular and of 16 m.m. dia and other end should have
female threads.
3.
Extension pieces should have threaded ends at both end.
4.
Extension piece length correspond to 130, and 370 m.m.
5.
Length of bass piece is 275 m.m.
6.
All threading corresponds to M10.
7.
Knurling should be done on each piece at one place.
8.
Measuring sleeve should have both faces parallel and flat. Length
of sleeve should be chosen such that the difference dimension A & C
is more than 150 m.m. (see if fig. 2). Sleeve length C should be more
than dimension LR.
Compressed air system:
1.
The hole in the inlet chamber for insertion of heating torch should
match with the standard torch shapes of Indian Oxygen Ltd;
without leaving a large clearance or causing insertion problem.
2.
A clamping device to hold the heating torch should be provided.
3.
A clamping device to hold the heating torch should be provided.
4.
Pressure gauge should be able to read the 0.5 at a difference air
pressure.
5.
Compressed air unit should be removable and kept seperately
when not in use.
IN GENERAL, THERE SHOULD NOT BE ANY BURR LEFT ON ANY
COMPONENT. THREADING DONE SHOULD OF HIGH STANDARD FOR
Bharat Heavy Electricals Limited
Rev 00,
7-98

116. STEAM TURBINE
500 MW
ERECTION
EASY ASSEMBLY & DISSEMBLY. SCALE SHOULD BE FLAT & MOVE
VERTICALLY UPWARD OR DOWN WARD FREELY.
DESIGNATION/IDENTIFICATION
Each gas heating device should be designated based on the stud heating hole,
20mm, 25mm or 32mm. On the inlet chamber the torch sizes (As per Indian
Oxygen Ltd; catalogue) to be used, shall be punched. Outer tube shall also be
marked for the heating hole size. Heating tube shall also be punched with the
O.D & thickness.
Measuring red extension piece, measuring sleeve shall bear on it, the exact length.
DESIGN DOCUMENT & PRE APPROVAL DOCUMENT
Minimum three copies of assembly drawing with item number, with its
nomenclature, calculations performed, material test certificate, valve
supplier test certificate, pressure gauge calibration record, and operation
manual should be submitted to EDM (ST) one month before final despatch
of the equipment for approval.
FUNCTIONAL TESTING & ACCEPTANCE
Supplier shall exhibit the suitability of operation of the heating device at BHEL works or at site (to be mutually agreed). Only after such successful field
demonstration device will be finally accepted. Suppleir has to demonstrate its
use & operation at his own cost. This requirement may be waved-off for
repeated order if felt necessary. If site trial show higher time of achieving
the elongation, repair replacement free of cost will be done by suppliers.
PACKING & DESPATCH
COMPLETE MEASURING DEVICE SHALL BE PUT IN A LINEN LINED DURABLE
BOX. ON THE LID OF THIS BOX FOLLOWING MARKING BE PUT "STUD
ELONGATION MEASURING DEVICE".
COMPLETE GAS HEATING DEVICE SHALL BE NICELY PACKED IN A WOODEN
BOX FOR AVOIDING DAMAGE DURING TRANSPORTATION. INSIDE THE
BOX ALSO, COMPONENTS SHOULD BE ELAMPED SUITABLY TO AVOID
DAMAGE.
Bharat Heavy Electricals Limited
Rev 00,
7-98

117. STEAM TURBINE
500 MW
ERECTION
ASSEMBLY OF BREECH NUT
The breech nut assembly used in between connection of main steam inlet line
and HP module. This type of connection are very useful in barrel type design of
HP module and helps in very fast assembly / dismantling of the module in
erection and subsequent overhaul of the unit. The number of breech nut depend
upon the numbers of steam entry connection for the HP module. However there
are generally two / four breech nut assemblies are used in a particular module.
A special care is must while making the breech nut assembly first time at site
during erection stage. The main steam inlet line connections are welded with the
HP casing inlet insert after assembly of the breech nut and no major correction of
breech nut is possible unless the inlet line are cut and rewelded.
PROCEDURE / SPECIAL CHECKS DURING ASSEMBLY OF BREECH
NUT AT ERECTION STAGE.
Ensure cleanliness of the inlet insert and HP casing matching flanges. A feeler
tight joint is to be ensured on these faces during its assembly.
Ensure that no burrs / high spots are left on threading portion of the breech nut
and all the threads are very smooth.
Ensure fitting of all radial / axial dowel pins of the breech nut before its final
assembly. These dowel pins causes serious problem during assembly of
breech nut at site if the holes are not properly reamed and dowel pins are
not fitted at works before dispatch. Many times after drilling / reaming of
holes at works the sizes are taken and pins are dispatched after
manufacturing without actual fitting.
Ensure compression of U seal ring before its assembly. The faces of the
ring may be checked for the line contact on a surface plate.
U-seal
High temperature molykote is to be used during assembly of breech nut in all
the area and matching flanges of inlet insert / HP casing are to be applied
with birkosite / stag-B jointly compound.
A 0.03 mm feeder tight joints are to be ensured on faces A & B from all the
inspection holes of the periphery before heat tightening of the breech nut.
The value of heat tightening is mentioned over the drawings.
Bharat Heavy Electricals Limited
Rev 00,
7-98

118. STEAM TURBINE
500 MW
ERECTION
The heat tightening device supplied with the machine is to be used for heat
tightening of the nut. The radial dowel pins of the breech nut are also to be
locked in position to avoid their falling at a later date.
The welding works of HP casing inlet insert pipelines may be taken up after heat
tightening of the breech nut.
Ensure that radial holes of breech nut are covered properly to avoid entry of any
foreign material.
The tightening of breech nut is done with the help of overhead crane in both the
condition i.e. during normal tightening and during heat tightening of the
nut. Proper size pins are to be used on periphery holes of breech nut to
avoid any damaged of periphery holes are any damaged to inside thread
of breech nut.
The tightening of breech nut is done with the help of overhead crane in both the
conditions i.e. during normal tightening & during heat tightening of the nut.
Proper size pins are to be used on periphery holes of breech nut to avoid
any damage of periphery holes are any damage to inside threads of the
breech nuts.
DISMANTLING OF BREECH NUT DURING OVERHAULING.
A similar procedure of heating the breech nut is used for loosing it. But before
the heating / loosing of breech nut the main steam inlet pipe lines need their
locking to avoid any type of load transferred on the threads on the breech nut.
Though perfect free joint are made during welding of the main steam inlet
pipelines with the breech nut but still the problem of piping pull are phased in
these area during the various reasons. Hence it is essential to lock the pipeline
to avoid its movement in any of the direction. The proper welding procedure are
to be used during locking of the pipelines if these are locked by welding method.
After loosing of the breech nut fully the locking of pipelines are to be made free.
The offset of pipelines may be recorded at this stage and any major variation in
pipeline need correction by cutting / rewelding of pipelines.
Bharat Heavy Electricals Limited
Rev 00,
7-98

119. STEAM TURBINE
500 MW
ERECTION
PROCEDURE/SPECIAL CHECKS DURING DISMANTLING/REASSEMBLY OF BREECH NUT IN OVERHAULING OF THE UNIT
Ensure locking of the inlet pipeline to avoid any load on the threads of the breech
nut due to pull / push of the pipe line an any of the direction while opening
it.
Ensure that all the radial dowel pins of the breech nut are intact before opening
the nut. If any of the dowel pins are loose then the same can be removed
before loosening the nut.
U-seal ring are to be ensured for their line contact and compression value before
reassembly.
Ensure fitting of radial dowl pins of the breech nut. These dowel pins play a
major role during its re-assembly.
Ensure parallellity of inlet insert and its alignment with the HP casing before its
assembly. The pipeline hangers may be adjusted at this stage if required.
Any major variation of alignment and parallelity of pipe line are to be corrected
before its assembly.
Similar procedure of assembly of breech nut may be used as explained during
erection stages.
During opening and re-assembly of breech nut if any additional load is
transferred due to pull / push of pipeline on breech nut threads then that
may cause seizure / damage of the breech nut threads.
OVERHAULING OF KWU DESIGN 200 / 250 / 500 MW
TURBINE IN CASE OF SPRING LOADED FOUNDATION
In case of spring loaded foundation the alignment and catenary of HP / IP / LP
/Gen. rotors are to be checked before lifting of any major component from the TG
deck . During checking of the rotor alignment, the instruction issued against
spring loaded foundation are to be followed. To cut short the time cycle of
overhauling the rotor alignment and catenary may also be corrected at this stage
itself so the further work of overhauling like removing of generator rotor, lifting of
LP rotor, lifting of HP module etc. may be taken up as per the requirement. This
will cut short the overhauling duration of the machine.
Bharat Heavy Electricals Limited
Rev 00,
7-98

120. STEAM TURBINE
500 MW
ERECTION
By following above procedure in overhauling of the unit the various works of
individual casing like fitting of radial keys, axial keys, casing packers etc. may
be taken up individually otherwise most of the above works are to be kept
pending for alignment of the HP / IP / LP / Gen. rotors . During correction of
rotors alignment the catenary of the shaft is also to be maintained. The
adjustment of shims in the bearing spherical / cylindrical seat is limited by + / 0.50 mm in pedestal seal bore values from its base values. The majority of
adjustment in achieving the catenary of the shaft may be done by adjusting the
shims in the TG deck spring.
Bharat Heavy Electricals Limited
Rev 00,
7-98

121. STEAM TURBINE
500 MW
ERECTION
CONSTRUCTIONAL DETAILS AND APPLICATION
PROCEDURE:
The following constructional/installation procedure shall be adopted.
1.
The turbine/ valve casing surface shall be cleaned with wire brush to
remove dust, dirt and such residues. Any contamination due to
oil/grease shall be removed with suitable solvent.
2.
The holding construction shall consist of MS strips of 25 x 3 mm
which shall be secured either with nuts and bolts or tack welded on
the pads already provided on casing surface for the purpose. The
holding construction shall be separately made for top and bottom half
of the casing for ease of maintenance. Wherever, required, additional
framework of MS strips shall be provided to impart adequate
strength to the holding structure.
3.
The MS Rod of 10 mm dia having length equivalent to insulation
thickness are welded on the MS frame at a pitch of 250 mm (max.0).
4.
Casing flange joint (parting plate) shall be provided with a separation
made out of Aluminium sheet ( 2 mm thick) as a distant line between
top and bottom half of the insulation.
5.
All thermocouples shall be masked with sleeves made out of
Aluminium sheet for proper access during maintenance and
replacement when and where necessary.
6.
Sprayed - on Rockloyd fibers (HT) shall be sprayed using specially
designed spraying equipments and accessories. The fibers shall be
processed to a desired pattern and finally conveyed to the application
point by means of a hose. The spray gun provided at the end of the
hose, supplies, the lloyd bond binder in the form of a finely
distributed concentric spray. The sprayed lloyd bond binder wraps
up the fibers and the wetted strike the surface to be insulated forming
a continuous monolithic layer. The required bulk density and the
Lloyd Bond binder proportion shall be achieved by controlling the
fiber output and lloyd Bond binder quantity. It shall be necessary to
use wooden pattas/probe for compacting the sprayed mass in
congested and other locations in order to provide required density
and thickness. Each layer shall be individually supported with the
help of wire netting and MS retainers. The surface temperature limit
Bharat Heavy Electricals Limited
Rev 00,
7-98

122. STEAM TURBINE
500 MW
ERECTION
shall be relaxed in restricted locations with the above mentioned
constraints.
7.
The Cat-9 (Bond Seal) finishing cement plaster shall be trowel applied
all over the insulated surface with a first coat of 4-5 mm. The final
coat of Cat-9 (Bond Seal) shall be applied after reinforcing Lloyd
fabric all around the plastered surface.
8.
The surface shall finally be finished with a coat of Lloyd FR pain
80/100 microns of special duty oil resistant and heat resistant coating.
NOTE: All the pipes below turbine casing where spray type of insulation is
finished and mattresses insulation starts, shall be finished with
Cat-9 hard setting compound upto 4 mtrs. Length.
INSULATION APPLICATION FOR PIPING
1.
The surface of the piping shall be cleaned with wire brush to remove
dust, dirt or other such residues.
2.
Likely Resin Bonded Rockloyd (LRB Mattresses) factory made
machine laid machine stitched mattresses conforming to IS : 8183
having GI Wirenetting on one side of design thickness shall then be
applied over the pipe surface.
3.
Individual layer of mattresses shall not exceed 75 mm in thickness
and shall be applied ensuring snug fit with the surface.
4.
The ends of wire netting at the longitudinal and circumferential joint
shall be butted together to ensure that no gap is left at the joints and
then laced with GI wire of 0.1 mm.
5.
All the joints in insulation shall be properly staggered.
6.
8/10 mm thick Cat-9 (Bond Seal) finishing cement plaster shall then
be trowel applied over the LRB mattresses for piping below the
casing, upto 4 mtr. Length.
7.
This shall finally be finished with the coat of Lloyd FR paint, special
duty oil resistant and heat resistant coating in thickness of 80 / 100
microns.
Bharat Heavy Electricals Limited
Rev 00,
7-98

123. STEAM TURBINE
500 MW
ERECTION
8.
For all other pipes 0.7 mm Aluminium sheet shall be provided duly
rolled and grooved by self tapping screws.
INSULATION APPLICATION FOR ESV’S IV’S MAIN STEAM VALVE LP BYE PASS
VALVE CHESTS.
1.
Above shall be insulated with sprayed Rocklloyd Fiber (HT) after
thorough cleaning with the same procedure as applicable for cylinder
casings.
2.
8 / 10 mm Cat-9 (Bond Seal), finishing cement shall then be provided
as explained in 9.6 above.
3.
The insulation shall finally be finished with Lloyd FR Paint special
duty oil resistant, heat resistant compound of 80 / 100 microns
thickness.
Bharat Heavy Electricals Limited
Rev 00,
7-98

124. STEAM TURBINE
500 MW
ERECTION
NAME OF
CONTRACT
PAPCKAGE
THERMAL
INSULATION
PACKAGE
FIELD QUALITY PLAN FOR
TURBINE INSULATION
MATERIAL RECEIPT/
STORAGE/PRE-ERECTED/
ERECTION/PRECOMMISSIONING/COMMISSION
ING/POLST COMMISSIONING
SNO
CHARACTERISTICS /
ITEMS
TYPE OF CHECK
INSTRUMENT
CLASS
QUANTUM//F
REQUENCY
OF CHECK
1.
MATERIAL RECEIPT
MATERIAL RECD. AT
SITE TO BE
CORELALTED WITH
chp/mdcc AND bATCH
nO. (WHICHEVER IS
APPLICABLE)
VISUAL
Minor
100
IN PROCESS
• Supporting os
Structure
• Surface
Preparation(Physical)
FORMAT
OF
RECORDS
-do-
-do-
-do-
-do-
• IS-3677
Log Book
Corelation
of Batch
No.
Thickness/
Size/WRT/
CHP/MDC
C
-do-
-do-do-
-do-do-
-do-do-
-do-do-
• • IS-6528
-do-do-
-do-
-do-
-do-
-do-
• IS-280
-do-
-do-do-
• Sprayable granulated
Mineralo Wool
• Bonding Agent
• SS Wirenetting/SS
wire
• GI Wirenetting/GI
Wire
• Self Setting cement
• Oil Resistance Paint
2.
REFERENCE
DOCUMENTS &
ACCEPTANCE
STANDARD
EQP NO.
REV.
DATE
PAGE
-do-do-
-do-do-
-do-do-
• IS-9743
• Berger Make
-do-do-
Visual
Physical
Minor
100 %
-do-
-do-
-do-
100 % check
for dirt, grease
etc.
• Spray of 1st layer of
insulation and
subsequent
layers(Thickness of
Insulation for each
layer).
• Fixing of SS wire
netting/ SS wire after
first layer and G.I.
wirenetting/ GI wire
after subsequent
layers.
Thickness
Thickness
Gauge
Minor
Three reading
of each
component to
be taken
Visual
Physical
Minor
100 %
• Supporting of
retainers
• Finishing with Plaster
Visual
Physical
Minor
100 %
Thickness
Thickness
Gauge
-do-
Three reading
on each
component to
be taken.
• Oil Resistance
compound painting
Covering capacity
Measuring
tape
-do-
These
reading, at the
beginning of
application, in
Bharat Heavy Electricals Limited
Rev 00,
7-98
Shall be free
from dirt, grease,
rust, wetness
etc.
BHEL Engg.
Approved
insulation
thickness
schedule.
SS Wirenetting/
wire shall be
used wherever
the temp. Is
more than 400
Deg.C. GI
wirenettin g/ GI
wire shall be
used.
BHEL Engg.
Approved
insulation
thickness
schedule.
Suppliers
Literatures
enclosed
(Annedxure-1)
Log Sheet
REMARK
S

125. STEAM TURBINE
500 MW
ERECTION
Mid. Course of
applications,
at the end of
application.
3.
SPRAYED OF
ROCKWOOL
Mix. On Components
(One per job.)
• hermal conductivity
BHEL
APPD.
lAB.
-doStandard
Template
Major
Two samples
IS-3346 & IS9742
T.C.
-do-do-
One Samples
-do-
-DO-
• Incombustibility
• Compressive
strength
LAB
LAB
-doMajor
-doOne sample
IS-3144 & 9742
BHEL Engg.
Approveod bulk
density schedule.
IS-3144 & 9742
IS-5724 & 9742
Total Ins. thickness
Thickness
gauge
Minor
• Hard setting cement
• Oil Resistant
Compound
• Surface temp. Over
finished surface
Thickness
- do -
Minor
-do-
Temperature
Measurement/
Thickness
Micromete
r
Digital,
contact.
Random
(Three
readings at
different pts.
Of surface.)
Five readings
Five readings
after drying
Five readings
at different
pts.
• Ambient Temp. At a
dist. Of 1.5 mtr. From
ccladding surface.
• Finished insulation
surface.
•
-do-
-do-
-do-
• Heat Resistance
• Density
4.
FINAL CHECKS
• Completion of
sprayed rockwool
insulation
Visual
Major
`
Minor
Three
readings at
different pts.
no cracks.
-DOT.C.
BHEL Engg.
Appd. Thick ness
schedule.
Log sheet.
Tender Spcen.
80-100 Microse.
BHEL Appt.
Procedure
Tender Spen.
Data sheet).
-do-
-do-do-
-do-
Note : 1. Wherever samples are drawn for testing at site, double readings must be ensure for
any re-tests, if required later on.
2. Pre-Commissioning checks to be finalised with Operational Services.
Bharat Heavy Electricals Limited
Rev 00,
7-98

126. STEAM TURBINE
500 MW
ERECTION
Bharat Heavy Electricals Limited
Rev 00,
7-98

127. STEAM TURBINE
500 MW
ERECTION
Bharat Heavy Electricals Limited
Rev 00,
7-98