1. A Report on industrial training at
“BHARAT HEAVY ELECTRICALS LIMITED”
Haridwar, India.
Manufacture and assembly of Turbo Generators and
Exciter motors
Under the able guidance of
Sh. P.S. Jangpangi (Sr. DGM) – Block 1
Submitted by
Gurtej Singh
B.Tech 4 Department of
Electrical Engineering IIT ROORKEE,INDIA
Uttar Pradesh, India
2. ACKNOWLEDGEMENT
Practical knowledge means the visualization of the knowledge,
which we read in our books. For this, we perform experiments and get
observations. Practical knowledge is very important in every field.
One must be familiar with the problems related to that field so that he
may solve them and become a successful person.
Aft
er
achievin
g
the proper goal
in
life,
an
engine
er
h
a
s
t
o
enter in profession
al
life. According to this life, he has to ser
ve
a
n
industry, may be public or private sector or self-
own.
For
the
efficie
nt
work in the field, he must be well
aware
of the practical
knowledge
as well as theoretical knowledge.
To be a good engineer, one must be aware of the industrial
environment and must know about management, working in such a
industry, labor problems etc., so that he can tackle them successfully.
Due to all the above reasons and to bridge the gap between
theory and practical, our engineering curriculum provides a
practical training of 30 days. During this period, a student works in
the industry and gets all type of experience and knowledge about
the working and maintenance of various types of machinery.
I have undergone my 30 days training (after VI Semester) at
BHARAT HEAVY ELECTRICALS LIMITED. This report is based
on the knowledge, which I acquired during my 30 days training
period at the plant.
4. INDEX
S.No.
1. INTRODUCTION
2. BHEL-A Brief Profile
. BHEL - AN OVERVIEW
4. HEEP: AN OVERVIEW
5. BRIEF SUMMARY OF THE BAR SHOP
6. TYPES OF TURBOGENERATORS
7. MATERIAL CHECKING
8. CONDUCTOR CUTTING AND END CLEANING
9. TRANSPOSITION OF CONDUCTORS
10. CROSSOVER INSULATION
11. PRESSING
12. ISS- TEST
13. FORMING OF BAR
14. ZERO PICKLING OF BAR END
15. COIL LUG MOUNTING
16. MAIN BRAZING
17. CONDUCTOR CUTTING, DEBBERING AND FACE
MILLING
`18. FIRST PICKLING
5. 19 BRAZING OF TOP PART
20. WATER FLOW TEST
21. NITROGEN LEAK TEST
22 THERMAL SHOCK TEST
23 HELIUM LEAKAGE TEST
24. INSULATION
25. IMPREGNATION AND
BAKING
26. FINISHING
7. CONDUCTING VARNISH COATING
8. TESTING
28.1 TAN-DELTA TEST
28.2 HIGH VOLTAGE TEST
9. DISPATCHED FOR WINDING
0. MOTOR WINDING
1. CONCLUSION
6. INTRODUCTION
I
n
1956, Ind
ia
took a maj
or
ste
p
towar
ds
the
establishment
of
its heavy
engineering
industr
y
when Bhar
at
Heav
y
Electrica
l
Ltd.
,
the
first
heavy electrical manufacturing
unit
of the country was setup at
Bhopal.
It progressed rapidly and three
more
factories went into production in 1965. The main aim of establishing
BHEL was to meet the growing power requirement of the country.
B.H.E.L appeared on the power map of India in 1969 when the
first unit supplied by it was commissioned at the Basin Bridge
Thermal Power Station in Tamil Nadu. Within a decade, BHEL had
commissioned the 100 unit at Santaldih. West Bengal.
BHEL had taken India from a near total dependence on imports to
complete self-reliance in this vital area of power plant equipment
BHEL has supplied 97% of the power generating
equipment.
BHE
L
has already supplied generating equipment to various
utilities
capab
le
of generating over 18000 MW power. Today BHEL can produce
annually; equipment capable of generating 6000MW. This will grow
further to enable BHEL to meet all of India’s projected power
equipment requirement. As well as sizeable portion of export targets.
Probably the most significant aspect of BHEL’s growth has
been it’s
diversification. The constant reorientation of the organization to meet the
varied needs
in
ti
m
e
with time a philosophy that has led to the development of a
7. tot
al
capabili
ty
from concepts to commissioning not only in the
field
of energy
but
also in
industry
and
transportation.
In the world power scene, BHEL ranks among the top ten
manufactures of power plant equipment and in terms of the spectrum of
products and services offered, it is right on top. BHEL’s technological
excellence and turnkey capabilities have won it worldwide recognition.
Over 40 countries in the world over have placed orders with BHEL
8. covering individual equipment to complete power stations on a
turnkey basis.
In 1978-79 export earnings reached Rs. 122 crores, the highest for
any one-
year.
BHE
L
ha
s
its headquarters at New
Delhi.
Its operations
are
spre
ad
ov
er
11
manufacturing plants and number of engineering and service
divisions located across the
country/ the service divisions includes a network of regional branch
offices throughout
India.
10. BHEL is the largest engineering and manufacturing enterprise in
India in the energy-related / infrastructure sector, today. BHEL is
ushering in the indigenous Heavy Electrical Equipment industry in
India-a dream that has been more than realized with a well-
recognized track record of Performa
A widespread network comprising of 14 manufacturing
companies, which have international recognition for its commitment
towards quality. With an export presence in more than 60 countries,
BHEL is truly India’s ambassador to the world. BHEL’s vision is to
become world class engineering enterprise, committed to
enhancing stakeholder value.
BHEL has:-
11. Installed equipment for over 90,000MW of power generation
for Utilities, captive and Industrial users.
Supplied over 25000 Motors with Drive Control System to
power projects, Petrochemicals Refineries, Steel, Aluminum,
Fertilizer, Cement plant, etc.
Supplied Traction electrics and AC/DC locos over 12000 kms
Railway network.
Supplied over one million Values to Power Plants and other
Industries
BHEL - AN OVERVIEW
12. The first plant of what is today known as BHEL was
established nearly 40 years ago at Bhopal & was the genesis of the
Heavy Electrical Equipment industry in India.
BHEL is today the largest Engineering Enterprise of its kind in
India with excellent track record of performance, making profits
continuously since 1971-72.
BHEL business operations cater to core sectors of the Indian
Economy like.
Power Industry
Transportation Transmission Defenses etc.
Today BHEL has
14 Manufacturing Divisions 9 Service Centers
4 Power Sector Regional Centers 150 Project sites
BHEL’s vision is to become world -class
engineering
enterpris
e,
committ
ed
to enhancing stakeholder value. The
greatest
strength
of
BHEL
is
its highly skilled and committed 44,000 employees.
Spread all over India & abroad to provide prompt and effective
service to customers.
13. BUSINESS SECTOR
BHEL operations are organized around business sectors to
provide a strong market orientation. These business sectors are
Power Indus and International operations.
POWER SECTOR
Power sector comprises of thermal, nuclear, gas and hydro
business. Today BHEL supplied sets account for nearly 65% of the
total installed capacity in the country as against nil till 1969-70.
BHEL has proven turnkey capabilities for executing power projects
from concept to commissioning and manufactures boilers, thermal
turbine generator set and auxiliaries up to 500MW.
It possesses the technology and capability to procure thermal
power generation equipment up to 1000MW.
Co-generation and combined cycle plants have also been introduced.
For efficient use of the high ash content coal-BHEL supplies
circulating fluidized boiler.
BHEL manufactures 235MW nuclear sets and has also
commenced production of 500MW nuclear set.
Custom-made huge hydro sets of Francis, Elton and Kaplan
types for different head- discharge combinations are also
engineered and manufactured by BHEL.
INDUSTRY SECTOR
BHEL is a major contributor of equipment and system to
important industries like
14. Cement
Petrochemicals Fertilizers
Steel paper Refineries
Mining and Telecommunication
The range of system and equipment supplied including captive
power stations
High speed industrial drive turbines Industrial boilers and auxiliaries Waste
heat recovery boilers
Gas turbines pump, valves, seamless steel tubes Heat exchangers
Process control etc.
TRANSPORATION :-
BHEL supplies a wide equipment and system to Indian Railways.
Electric locomotive
Traction electric and traction control equipment
15. TELECOMMUNICATION:-
BHEL also caters to Telecommunication sector by way of
small, medium and large switching system.
BHEL has been divided into many blocks:-
1). Block-1:-
In block one turbo generator, generator, exciter motors
(A.C&D.C) are manufactured & assembled
2). Block-2:-
In block two large size fabricated assembliescomponent for
power equipment are manufactured & assembled.
3) Block-3:-
In block -3 steam turbine, hydro turbines, and gas turbines,
turbines blade are manufactured & assembled
4) Block-4:-
In block -4winding for turbo generator, hydro generator,
insulation of A.C&D.C motors insulating component for turbo
generator, hydro generator motors are manufactured & assembled
5) Block-5:-
In block - 5 fabricated parts of steam turbine water box, hydro
turbine turbines parts are manufactured & assembled
6) Block-6:-
In block -6 fabricated oil tanks hollow guide blades, rings,
stator frames rotor spiders are manufactured & assembled
7) Block-7:-
16. In block -7all types of dies including stamping dies,
stamping
for
generators
&motors are manufactured & assembled
8) Block-8:-
In block -8 LP heaters, ejectors, steam coolers, oil
coolers, ACG coolers, oil tanks are manufactured &
assembled
MANUFACTURING DIVISIONS
Heavy Electrical Plant, Piplani, Bhopal
Electrical Machines Repair Plant (EMRP), Mumbai Transformer Plant P.O.
BHEL, Jhansi.
Bharat Heavy Electrical Limited :
Central Foundry Forge Plant., Ranipur, Hardwar Heavy
Equipment Repair Plant, Varanasi.
Insulator Plant, Jagdishpur, Distt. Sultanpur.
Heavy Power Equipment Plant, Ramachandra Puram, Hyderabad
High Pressure Boiler Plant & Seamless Steel Tube Plant,
Tiruchirappalli.
Boiler Auxiliaries Plant, Indira Gandhi Industrial Complex, Ranipet.
Industrial Valves Plant, Goindwal.
Electronics Division :
18. HEEP: AN OVERVIEW
Over the years, Bharat Heavy
Electrical
Limited has
emerged
a
s
world class engineering and Industrial giant, the best of its kind
in
entire South East Asia. Its business profile
cuts
acro
ss
various secto
rs
o
f
engineering/power utilities and
industry.
Th
e
compan
y
toda
y
enjoys national and international presence featuring in the " fortune
international-500” and is ranked among the top 12 companies of the
world, manufacturing power generation equipment. BHEL has now 14
manufacturing division, 8
service
centers and 4power power
sectors
regional centers besides a
large
number of project sites spread
over
India and abroad.
The company is embarking upon an ambitious growth path
through clear vision, mission and committed values to sustain and
augment its image as a world-class enterprise.
VISION
A world-class innovating, competitive and profitable
engineering enterprise providing total business solution.
MISSION
To be the leading Indian engineering enterprise providing quality
products system and services in the field of energy, transportation,
infrastructure and other potential areas.
20. Respect for dignity and potential of individual
Loyalty and pride in the company
Team playing
MANUFACTURING PROCESS OF
TURBO GENERATOR & STATOR BAR
BRIEF SUMMARY: ABOUT THE BAR SHOP
This shop is meant for manufacturing of stator winding coils of generator
that may be turbo generator or hydro generator.
HR BARS
Manufacturing of bars of different capacity depends upon the water head
available at site. The hydro generator is air called generator of lesser length.
TURBO GENERATOR BAR
For the turbo generator the manufacturing of bars of standard capacity such
as 100 MW, 130MW, 150MW, 210/235MW, 210/250MW. This plant has
capacity and technology to manufacturing 800 MW generators.
21. TYPES OF GENERATORS
The generator may be classified based upon the cooling system
used in the generators such as;
THRI, TARI, THDI, THDD, THDF, THFF, THW
• =i.e. Turbo Generator or Hydro Generator.
H/A =i.e. Hydrogen Gas or Air.
R/D/F/I =i.e. Radial, indirect, forced, direct etc.
I/D/F=i.e. Indirect cooling, direct cooling, forced cooling.
W =i.e. cooling media used for cooling of stator coil e.g.
water.
MATERIAL CHECKING
First we check the material of the conductor. And the total insulation upon
the conductor. The width of the copper conductor
should be:
a. For Lower bar = 8 x 2.8mm (Solid)
b. For Upper bar = 8 x 1.3mm (Solid)
c. For Hollow
conductor=
8 x 4.6 x 1.5mm
(Solid)
CONDUCTOR CUTTING AND END CLEANING
22. This process is done by the automatic CNC machine, in this
process the length of lower bar & upper bar is decided as following
as per drawing-
Lower Bar
a. Solid conductor length = 10,200mm (10
Plates)
b. Hollow conductor
length
= 10,200mm (10 Plates)
Upper Bar
a. Solid conductor length = 10,050mm (10
Plates)
b. Hollow conductor
length
= 10,050mm (10 Plates)
This insulation is removed from both ends after the cutting of
conductor i.e. 500mm for both lower & upper bar.
TRANSPOSITION OF CONDUCTOR
Transposition means changing or shifting of position of each
conductor in active care (slot) part. After cutting the required
number of conductors are arranged on the comb in staggered
manner and than bands are given to the conductor with the help of
bending die at required distance.
23. Setting of die
a. Comb of setting for lower bar’s
Die 1st
Die 2nd
Die 3rd
2200.2mm 3735.3mm 6586.2m
m
b. Comb of setting for Upper bar’s
Die 1st
Die 2nd
Die 3rd
2109mm 3620.2mm 6496.2m
m
This process is repeated to making another half of the bar.
CROSS OVER INSULATION
Cross over insulation is give to the conductor for the protection in which
the insulating spacer are provided at the cross over portion. In
this insulation the No-max paper is used.
Here the filter material (insulating putty of moulding
micanite) spacer is provided along the high of bar to maintain
the rectangular shape. The size of spacer should be –
1st
Band = 146m
m
2nd
Band
= 219m
m
3rd
Band = 292mm
STACK CONSOLIDATION OR PRESSING
24. The core part of the bar stack is pressed in press under the
pressure between 70kg to 80kg (various from product to product)
and the temperature between 90 Deg.C to 160 Deg.C for a given
period. Here four bars is pressed in one time and six to eight plates
are used for pressing. After that the consolidated stack is withdrawn
from the press.
INTER STAND SHORT TEST (I.S.S.Test)
In this test first we make the distance to the non insulating portion
of the bar. Here we check the short between any two conductor.
After this test the bars are again go for the second pressing. In
which attached full slot separator between two half bar no-max
paper and tapped with transparent film. In this test if any error is
found then it has to be rectified.
FORMING OF BAR
In this operation the straight bar stack is formed as per overhang
profile. In this process bars should be formed on universal former
and marked for the thermal space. After it they are moved for
cutting of extra conductor.
25. ZERO PICKLING OF BAR END
Pickling is the process of the cleaning of components by the
chemicals. The pickling solutions are:
a. Water = 100 parts by
weight
b. Sulphuric Acid = 10 parts by
weight
c. Phosphoric Acid = 5 parts by
weight
d. Hydrogen per
Oxide
= 5 parts by
weight
The temperature should be maintain 50 Deg.C to 60 Deg.C.
The end portion of bar is dipping in this solution upto 10 to 15 min.
During this pickling process some aciditic properties are effected
to the end portion of bar. So to neutralization of it dipped the bars again
in the ammonia solution. For the shining of end part the bars are dipped
in ethyal alcohol (C2H5OH) solution and dry with nitrogen Pressure.
COIL LUG MOUNTING
In this process contact sleeve and the bottom part of the water box are
adjust at the give dimensions. The operation of mounting of contact sleeve
and bottom part of water box is complete in following
steps-
26. a. Check the dimension of contact sleeve and water box bottom part.
b. Stand by bar for setting of lug.
27. c. Setup to the solid conductor in each row as per drawing.
d. Then insert the contact sleeve upon the solid and hollow conductor
and temporally installed to it. And also installed the bottom part of
water box.
e. Maintain the gap between contact sleeve and bottom part of water
box approx 20mm.
After the lug mounting cutting of extra solid conductor.
MAIN BRAZING
There are the following steps to brazed the lug.
a. Stand by bar of setting for brazing.
b. Then heated the lug point through the two indictor at the
temperature of 700 Deg.C .
c. For brazing use brazing alloy L-Ag-15P by four person. This is the silver
platinum alloy wire of melting point 700 Deg.C to 750 Deg.C.
d. This Temperature is give through the laser rays.
CONDUCTOR CUTTING, FACE MILLING AND DEBBERING
After the main brazing bars is moved for cutting of extra part of
conductors as per drawing. Here cut the end part of the bottom part
of water box and taken for face milling.
28. In this process the conductor is given the accurate shaped as per
the measurement and it is taken in account that any part of the
surface is not left uneven and dull.
Then in Debbering, the bars edges are many a time left with twigs
and sharp needle type mettle cutting known as bar and this process
of removing is known as Debbering.
FIRST PICKLING
This is the same process of pickling which is done before the lug
mounting or zero pickling. After this pickling process the bar is
moved the brazing of top part of water box in both side.
BRAZING OF TOP PART
Thought the induction process the top part of water box is brazed in
both side.
As per the previous main brazing first we stand by bars of
setting for brazing then we attached the top part from the bottom
part of water box. Then healed the top part by top inductors at
the temperature of 400Deg.c.
29. For this type of brazing use L-Ag-40Cd. This is the alloy
silver academy which have 40% cadmium and the melting point
is 400 Deg.C to 500 Deg.C. This brazing is done for both end.
After the brazing the bars is go for second pickling which is the
same process as previously explain.
WATER FLOW TEST
Thought this test check the flow water equivalently in the hollow
conductor of the bar. There is the following steps of checking-
a. Water should be exit all the total hollow conductor.
b. If some burrs are jammed it should be removed to give very high
pressure of water and clean with the help of solid wire.
c. The main point of testing is that the water flow into the bar and exit
from the water box fall down approximately to cover 1 Mtr. From
each conductor.
NITROGEN LEAK TEST
In this test the bar is tested for leakage into the components of bar. In
30. this test flow of nitrogen gas with pressure of 10kg/Cm
THERMAL SHOCK TEST
The cycles of hot (80 Deg.C) and cold (30 Deg.C) water are flew
thought the bar to ensure the thermal expansion and contraction of
the joints. The time of low of hot & cold water should be approx 32 to
40min and give the time between to flow of hot & cold water is 5 min.
this process is applied atleast 8 hours.
HELIUM LEAKAGE TEST
In this test the bar’s end is tested to flow of helium gas with the
given pressure if the end part of the bar is leakage then the helium
gas is covered the surface of water box and indicator indicate the
point of leakage.
INSULATION
For the insulation sunmika therm tape or sunmika pleese tape is used
which is the combination of mica + glass + varnish. It is used for corona
protection. In this insulation to layer of pleese tape + to layer of therm tape
and after them again to mica pleese tape is used.
31. Process of Insulation
a. Clean the bar.
b. Clean with chemical or thinner.
c. Taping
d. Realizing film from the mica plastic section.
In insulation the wall thickness of insulation is subjected to the
generating voltage of the machine.
IMPREGNATION AND BAKING
1. Thermoreactive system: In case of rich resin insulation the bar is
pressed in closed box in heated condition and baked under pressure
and temperature as per requirement for a given period.
2. Micalastic system: In case of poor resin system the insulated bars
are heated under vaccum and impregnated (dipped) in heated resin
so that all the air gaps are filled, layer by layer with resin then extra
resin is drained out and bars are heated and baked under pressed
condition in closed box fixture.
VPI Micalastic System
32. The bars already laid in closed fixture and full fixture is impregnated
in resin and then fixture with box is baked under given temperature
for the given duration.
VIP Micalastic System
The individual bar is heated in vaccum and impregnated in resin.
Then bar is taken out and pressed in closed box fixture and then
baked at given temperature for given duration.
FINISHING
The baked and dimensionally correct bars are sanded-off to
smoothen the edges and surface calibrated if required for the
dimension.
CONDUCTING VARNISH COATING
OCP (Outer Corona Protection) Coating: The black semi-
conducting varnish coating is applied on the bar surface on the
core length.
ECP (End Corona Protection) Coating: The grey semi-conducting
varnish is applied at the bend outside core end of bars in gradient to
prevent from discharge and minimize the end corona.
33. TESTING
1. Tan Test: This test is carried out to ensure the healthiness of
dielectric (insulation) i.e. dense or rare and measured the
capacitance loss.
2. H.V. Test: The each bar is tested momentarily at high voltage
increased gradually to three times higher than rated voltage.
DISPATCHED FOR WINDING
If the bar is passed in all the operation and testing after completing
then the bar is send for stator winding.
TURBO GENERATORS
(a) Air Cooled Generators Upto 200 Mw Range (Type:
TARI ) Salient Design Features
Stator core and rotor winding direct air-cooled
Indirect cooling of stator winding Horizontally split casing design of
stator
34. Vertically side mounted coolers in a separate housing
Micalastic bar type insulation system Separately assembled stator core and
winding for reducing the manufacturing cycle Brushless/static
excitation system
b) Hydrogen Cooled Turbogenerators Of 140-260 Mw Range (Type:
THRI ) Salient Design Features
Stator core and rotor winding directly hydrogen cooled
Indirect cooling of stator winding Rigid core bar mounting
Micalastic insulation system End shield mounted bearings
Top ripple springs in stator slots Ring type shaft seals
Symmetrical ventilation.
35. MOTOR WINDING
9.1 Technical Requirements
(1) Count the coil groups in the anti clock wise direction locking
from the connection end.
(2) Leads of the coils groups lying on the outer periphery of the
overhang position shall be the finish and those lying on the inner
periphery shall be the start to coil groups.
(3) Leads shall be taken form the coil side lying at inner periphery
of slot No.1.
(4) The coil group No.1 shall Lie at top with its axes coinciding
with the vertical axis of the frame.
36. (5) Take out terminal leads 02 U2, V2, W2 for left hand side
terminal box and 02 U1, V1, W1 for right hand side terminal box.
When looking form the connection end.
Circuit diagram:-
WINDING DIAGRAM OF MOTOR WINDING
9.2 Winding data
NO. OF PHASE 3
NO. OF POLES 6
PHASE CONNECTION Y
NO. OF PARELLEL PATH 2
NO. OF COIL GROUP 1
39. CONCLUSION
T
h
e
second phase of training has proved to be quite
faithful.
It
proved
an opportunity for encounter with such huge machines
like
turbo-generator hydro generator etc.
The architecture of B.H.E.L., the way various units are linked
and the way working of whole plant is controlled make the students
realize that Engineering is not just structural description but greater
part is planning and management. It provides an opportunity to
learn tech. Used at proper place and time can save a lot of labour.
But there are few factors that require special mention.
Training
is not carried in true spirit. It is recommended that there should
be
projectors especially for trainees where presence of authorities is ensured.
40. However, training has proved to be satisfactory. It has allowed
us an opportunity to get an exposure of the practical
implementation of theoretical fundamentals.
