It is presentation about ASME piping Codes & Standards for piping Design.

1. CODES & STANDARDS

2. PIPING
• Codes, Standards & Regulations
– ASME
– DIN
– TRD
– BS
– IBR

3. • Codes and Standards:
•
• Several groups have written codes and standards for
materials, inspection, design, stress analysis, fabrication,
heat treatment, welding and construction of pipes and
piping components. Regulations, practices, rules and laws
are also available for use of piping. Certain aspects are
mandatory and certain aspects are recommendatory. The
commonly used American Codes and Standards on piping
are given below:

4. • 1. ASME B31.1 - Power Piping
• 2. ASME B31.2 - Fuel Gas Piping
• 3. ASME B31.3 - Process Piping
• 4. ASME B31.4 - Pipeline Transportation Systems for Liquid
• Hydrocarbons and other Liquids.
• 5. ASME B31.5 - Refrigeration Piping
• 6. ASME B31.8 - Gas Transmission and Distribution Piping
• Systems
• 7. ASME B31.9 - Building Services Piping
• 8. ASME B31.11 - Slurry Transportation Piping Systems.

5. • Through the use of codes and standards, safety and uniform economy
are obtained. The codes and standards primarily cover the following
aspects:
• 1. Factors safety
• 2. Material property
• 3. Thickness calculation
• 4. Loads
• 5. Load combinations
• 6. Stress limits
• 7. Stress intensification factors
• 8. Flexibility factors
• 9. Supports
• 10. Flexibility analysis.

6. • Even though the use of codes and standards is not a legal requirement
the same becomes a legal requirement in a contractual situation.
Certain regulations are legally binding. The Indian Boiler Regulations,
1950 (IBR) is binding on the Indian Boiler-makers and Boiler-users, of
certain kind of boilers. The codes and standards do not cover all
aspects of the piping. The codes and standards are not textbooks.
They do not cover the theory. They provide answers to the following
aspects:
•
• 1. Know what
• 2. Know how

7. • The “Know why” is not covered by the codes and standards. The
“Know why” is learned by study, experimentation, application and
experience. In most of the situations, a knowledge of “Know what”
and “Know how” is sufficient to solve the problems. A knowledge of
“Know why” will help in handling the following situations:
•
• 1. Material selection
• 2. Applicable code and standards
• 3. Evaluation of the deviations
• 4. Use of new fabrication and inspection methods.

8. • Codes and Standards:
•
• The following codes and standards are referred:
•
• 1.ASME-I : Rules for Construction of Power Boilers
• 2.ASME B31.1-1998 : Power Piping
• 3.ASME B16.5-1996 :Pipe Flanges and Flanged Fittings – NPS ½ through 24.
• 4.IS 1239 (Part-I)-1990 :Mild Steel Tubes, Tubular and other
• Wrought Steel Fittings - Mild Steel Tubes
• 5.IS 1239 (Part-II)-1992 :Mild Steel Tubes, Tubular and other
• Wrought Steel Fittings – Steel Pipe Fittings

9. • Nominal Pipe Size (NPS):
•
• The Nominal Pipe Size (NPS) in an ASME method of indicating the
approximate outside diameter of the connected pipe in inches. Note
that the unit (inch) is not followed after the designation.
•
• Class of Fittings:
•
• The class of fittings is an ASME method of indicating the pressure
carrying capacity of the fittings.

10. • Schedule of Pipes:
• The schedule of pipes is an ASME method of indicating the pressure
carrying capacity of the fittings.
• Types of Flanges:
• The following types of flanges are used:
•
• 1. Threaded
• 2. Socket welding
• 3. Blind
• 4. Slip-on welding
• 5. Lapped
• 6. Welding neck.
•

11. • Pressure – Temperature Rating:
•
• Ratings are maximum allowable working gauge pressure at
a given temperature. These values are given in ASME
B16.5.
• Selection of Flanges:
•
• The flanges are selected based on the application, pressure,
temperature and size.

12. ASME Section-I PG 9 – Materials Specifications List.
ASME Section-II Part-A – Material Specifications.
- SA106, 192, 299, 210, 213, 234, 515.
ASME Section-II Part-D – Table IA – Maximum Allowable Stress
- Table Y, U
ASME Section-II Part-A
Tubes - SA450 - Specification for General Requirements for tubes.
Pipes - SA530 - Specification for General Requirements for Pipes.
Fittings - SA234 - Specification for Piping Fittings.
Drum combined bending Stress – BS 1113, ANNEX-B.
REFERENCES

13. Boiler Codes have been written by various nations in the past
century to ensure safety of personnel and to avoid loss of property. Boiler
codes cover the whole gamut of activities including Design, Fabrication,
Testing, Construction and Operation. Although these codes are framed on a
common intent, there are variations on the degree of conservation on
different aspects. One such area where variations do exist between Boiler
Codes is the criteria stipulated for calculating the allowable stresses. In the
present day context of evolving competitive design without sacrificing the
safety needs laid down in the boiler codes, an attempt has been made by
comparing the various aspects in the design like allowable stress, Design
temperature criteria, the various formulae used to determine the thicknesses
for drums / shells, headers, tubes, dished / flat ends, etc, other aspects like
minimum design requirements for drums/headers & tubes and presented in
annexures. The various aspects of IBR Regulations are called out and
consolidated against major items like drum, headers, lines & links, etc. The
following codes have been considered for the study:-
1.IBR 1950
2.ASME Section-I
3.BS 1113
4.DIN TRD 300.
COMPARISON OF BOILER CODES

14. The observations made between various boiler codes in respect
of design are given below:-
1) Yield strength at room temperature is not considered in BS1113
and IBR whereas factor of safety at room temperature in ASME
Section-I is 1.5 and the same in TRD is 2.4.
For tensile strength at room temperature, both IBR and BS1113
considers a factor of safety of 2.7 whereas in ASME Section-I
indicates 3.5 and not considered in TRD. In the case of rupture
strength, all codes consider factor of safety as 1.5 except
BS1113 which shows 1.3.
2) In the case of Design Pressure of the boiler IBR alone considers
pressure drop for various components inline with erstwhile ISO
R831 whereas the rest of the codes indicate the boiler to be
designed for drum design pressure.
3) In respect of Design Temperatures, all codes apply some fixed
temperature allowances over the medium temperature except
ASME Section-I which states that parts to be designed for actual
metal temperatures.

15. 4) Comparison material grades among various codes indicate
specification as common for most of the material
compositions. DIN (GERMAN) indicates a specification 12
Cr, 1 Mo, ¼ V composition (X20) which is not finding a
place in both ASME & BS1113. Also, when there is a
specification indication for austenitic steels like 18 Cr 8 Ni,
18 Cr 10 Ni Cb in both ASME & BS1113, there is no such
grade under TRD 300.
It is concluded that ASME Section-I gives the most
stringent criteria on design for deciding the allowable
stresses (Tensile / 3.5) compared to other international
codes below creep region. BS1113 & IBR are same in
respect of design criteria for allowable stresses (Tensile /
2.7). TRD 300 is in between ASME & IBR / BS1113 since the
allowable stress values of DIN falls in between them.
Above creep region, BS1113 gives more liberal criteria
(Creep rupture / 1.3) compared to other international codes.
Weight savings arising out of adopting BS1113 compared
to ASME Section-I is also illustrated in an annexure.

16. Sl.No. Item Description
01. Applicability of Code Regulations
02. Maximum Allowable Working Pressure
03. Design Pressures & Design Temperatures
04. Comparison of Codes
05. Design Stresses - Factors of Safety
06. Comparison of Material Grades
07. Temperature Limits for various Steel Grades
08. Design - Calculation of Thickness Required
09. Openings in Shell
10. Ligament Efficiency
11. Drum / Headers comparison - 2 sheets
12. Tubes comparison
13. Relationship between Allowable Stress, Weight Savings
14. IBR Regulations - Clauses - 2 sheets
15. IBR Regulation Numbers - Ascending Order - 8 sheets
16. Requirements as per ASME Section-I - 3 sheets
17. Salient Clauses of BS1113 - 3 sheets
COMPARISON OF BOILER CODES

17. APPLICABILITY OF CODE REGULATIONS
IBR Applicable to boiler that is a closed vessel exceeding
22.75 litres in capacity which is used to generate
steam under pressure.
ASME Sec.
I
Applicable to boilers in which the steam or any other
vapour is generated at a pressure more than 15 PSI
(g).
BS 1113 The rules specify the requirements for the water tube
steam generating plant subject to internal pressure.
TRD 300 The rules apply to steam boilers and to feed water
preheaters, SH with shut off devices, RH, DESH,
steam and hot water lines and fittings which are
regarded as part of the steam boiler installation.

18. MAXIMUM ALLOWABLE WORKING PRESSURE
IBR It is the working pressure of any component of the
boiler.
ASME Sec.
I
It is the maximum pressure to which any part of
the boiler is subjected to except when SV or SRV or
Valves are discharging at which time the MAWP
shall not be exceeded by more than 6%.
BS 1113 It is the highest set pressure on any SV mounted on
the steam drum.
TRD 300 For steam generators, the design pressure shall be
the allowable pressure.

19. AREA IBR ASME
SEC.I
BS
1113
DIN TRD
300
DESIGN PRESSURE Drum design
pressure with
pressure drop
Drum design
pressure
Drum design
pressure
Drum design
pressure
RADIATION 50C 50C 50C
CONVECTION 39C 35C 35C
ECONOMISER 11C 25C 15+2xAct.
wall thick)
C
Max. 50C
WATER WALLS / SH WALLS 28C 50C 50C
GAS TOUCHED DRUMS/HEADERS 28C 25C 20C
ACTUAL
METAL
TEMPERATURE
371C
(MIN)
FOR
GAS
TOUCHED
PORTION
DESIGN PRESSURES & DESIGN TEMPERATURES -
ALLOWANCES USED IN VARIOUS CODES

20. IBR 1950 ASME SEC.I BS 1113 DIN TRD 300 REMARKS
DESIGN PRESSURE DESIGN PRESSURE
WITH PRESSURE
DROP
DRUM DESIGN
PRESSURE
DRUM DESIGN
PERSSURE
DRUM DESIGN
PRESSURE
DESIGN
TEMPERATUE
ALLOWANCE
RADIATION
50C
ACTUAL METAL
TEMPERATURE
371C (MIN)
50C 50C
CONVECTION 39C 35C 35C
ECONOMISER 11C 25C (15 + 2 Se) C
Max. 50C
Se - ACTUAL WALL
THICKNESS in mm.
WATER WALL 28C 50C 50C
TUBE THICKNESS
FORMULA tmin
PD
--------- + *C
2f + P
PD
--------- + 0.005D
2f + P
PD
---------
2f + P
PD
---------
2f + P
P=DESIGN PR.
D=OUTSIDE DIA
f=ALLOWABLE STRESS
CORR. TO DESIGN
METAL TEMP.
FACTOR OF SAFETY
Et R
1.5 , 2.7
SR SC
1.5
Et R
1.5 , 3.5
SR SC
1.5
Et R
1.5 , 2.7
SR
1.3
Et R
1.5 , 2.4
SR
1.0
Et = YIELD STRENGTH
R = TENSILE STRENGTH
SR = RUPTURE
STRENGTH
SC = CREEP STRENGTH
FOR ASME MATERIALS ALLOWABLE STRESS CAN BE TAKEN DIRECTLY FROM ASME SEC.II PART-D
COMPARISON OF CODES
*C = CORROSION ALLOWANCE = 0.75mm FOR P ≤ 70 bar; 0 mm FOR P > 70 bar

21. PROPERTIES IBR ASME
SEC.I
BS 1113 DIN TRD
300
Min. yield strength at Room Temperature --- 1.5 --- ---
Min. yield strength at Design Temperature --- --- 1.5 1.5
Average yield strength at Design
Temperature
1.5 1.5 --- ---
Min. ultimate tensile strength at Room
Temperature
2.7 3.5 2.7 2.4
Average creep rupture strength for 100,000
hours life at Design Temperature
1.5 1.49 1.3 1.0
Average creep strength for 1% creep in
100,000 hours at Design Temperature
1.0 1.0 --- ---
 For Austenitic steels, FS = 1.35
 To be used at temperature below 1500F
 For components without an acceptance test certificate to DIN 50049, FS shall be increased by 20%.
DESIGN STRESSES – FACTORS OF SAFETY IN VARIOUS CODES

22. Max. Service
Temperature

475C
885F
500C
930F
550C
1020F
560C
1040F
575C
1065F
600C
1110F
625C
1155F
Gr.A
A192
Gr.B
Gr.A1
Gr.C
Gr.C T1
P1 T2 / P2 T12/P
12
T11/P1
1
T22/P2
2
T9/P9
BS
3059-3602-
3604
360 410 440-
460
490Nb 243 620 621 622 660 629
DIN
(GERMANY)
17175
VdTUV.B1
(Werkstoff-Nr.)
St.35.
8
1.030
5
St.45.
8
1.040
5
17
Mn4
1.048
1
19
Mn5
1.0482
15
Mo3
1.541
5
16
Mo5
1.542
3
15Ni
CuM
oNb
5
1.63
68
13Cr
Mo44
1.7335
10Cr
Mo
9 10
1.7380
(14M
o
V63)
1.771
5
(X12Cr
MO
91)
1.7386
GOST
(RUSSIAN)
TY 14-3-460-75
20 15 XM 12
X1
MF
(15X
IMI
F)
JIS (JAPAN)
G3456 G3458
G3461 G3462
STPT
38
STB
35
STPT
42
STB
42
STPT
49
STPA
12
STBA
12
STPA2
0
STBA2
0
STPA2
2
STBA2
2
STPA2
3
STBA2
3
STPA2
4
STBA2
4
STPA2
6
STBA2
6
NF A 49-213
(FRENCH)
TU37-
C
TU42-
C
TU48-
C
TU52-
C
TU15
D3
TU15C
D
2.05
TU13C
D
4.04
TU10C
D
5.05
TU10
CD
9.10
TU
Z10
CD9
ASME
SA 106
SA 192
SA 209 - SA 210
SA 213 - SA 335
 This is indicative only. However, the actual maximum service temperature for various steels shall be limited as prescribed in the relevant codes.
COMPARISON OF MATERIALS GRADES

23. Sl. Nominal MATERIAL SPECIFICATION Temp.
No. Composition ASME Section-I DIN – TRD 300 BS 1113 Limit C
01. Carbon Steel SA178 Gr.C, Gr.D,
SA192, SA210 Gr.A1
& Gr.C
SA106 Gr.B, Gr.C
St 35.8
St 45.8
BS3059 P2 S2 360, 440
BS3602 P1 360, 430, 500
Nb
427
02. ½ Mo SA209 T1 15 Mo3 ---- 482
03. 1 Cr ½ Mo SA335 P12
SA213 T12
13 Cr Mo 44 BS3059 P2 S2 620
BS3604 P1 620 – 440
535
04. 1¼ Cr ½ Mo SA213 T11
SA335 P11
---- BS3604 P1, 621 552
05. 2¼ Cr 1 Mo SA213 T22
SA335 P22
10 Cr Mo 910 BS3059 P2 S2 622-490
BS3604 P1, 622
577
06. 9 Cr 1 Mo ¼ V SA213 T91
SA335 P91
X 10 Cr Mo V
Nb91
----- 635
07. 12 Cr 1 Mo ¼ V ----- X 20 Cr Mo V 121 BS3059 P2 S2 762
BS3604 P1 762
700
08. 18 Cr 8 Ni SA213 TP304 H ----- BS3059 P2 304 S51
BS3605 – 304 S59 E
704
09. 18 Cr 10 Ni Cb SA213 TP347 H ----- BS3059 P2 347 S51
BS3605 347 S59 E
704
TEMPERATURE LIMITS FOR VARIOUS STEEL GRADES OF TUBES / PIPES

24. AREA IBR ASME SEC.I BS 1113 DIN TRD 300
Tube
thickness
PD
+ C
2f + P
PD
+0.005D
2f + P
PD
2f + P
PD
2f + P
Shell
thickness
PR
+ 0.75
fE  0.5 P
PR
fE  (1 Y) P
PR
fE  0.5 P
PR
fE  0.5 PE
Dished end
thickness
PDK
+ 0.75
2f
PR
2f  0.2 P
PDK
2f
2P
R 1+ 1
2f  P
Flat end
thickness
CP
d + C
f
CP
d
f
P
Cd
f
P
Cd
f
DESIGN - CALCULATION OF THICKNESS REQUIRED IN VARIOUS CODES

25. IBR
PD
8.08 [Dt (1  K)]1/3 K =
1.82 St
ASME Sec. I
PD
8.08 [Dt (1  K)]1/3 K =
1.82 St
BS 1113
PD
8.08 [Dt (1  K)]1/3 K =
1.82 St
TRD 300
t branch
For dia of Opg.  50 mm,  2
t shell
For dia of Opg > 50 mm,
opg dia t branch
if  0.2, then  2.
shell ID t shell
opg dia t branch
if > 0.2, then ≠ 2.
shell ID t shell
OPENINGS IN SHELL

26. EFFICIENCY ASME IBR BS 1113
Longitudional
P  d
P
P  d
P
P  d
P
Circumferential
PC  d
PC
PC  d
PC
PC  d
PC
Diagonal J + 0.25  (1 0.01 Elong) 0.75 +J
0.00375 + 0.005 J
2
A + B+ (A  B)2 + 4C2
2
A + B+ (A  B)2 + 4C2
TRD 300 gives lengthy equations for calculating the ligament efficiency factors. For a single opening,
’all
di A + A’ 
all
VA = and for multiple openings,
’
all
SV 2 AP+ A’  A’ 
all
’all ”all
di A0 + A1 + A2
all all
VL =
’
all ”all
SV AP0 (1+cos2)+2AP1+2AP2+A1+A2  A1  A2
all all
LIGAMENT EFFICIENCY

27. DESCRIPTION IBR ASME SEC.I BS 1113 DIN TRD 300
Min. Plate thickness for shell 6 mm 6 mm 6 mm 3 mm
Type of weld joint Single or double ‘U’ or ‘V’
type.
Double welded butt type.
The shape shall be such as
to permit complete fusion
and complete joint
penetration.
Double ‘V’ Type or ‘U’ type. Double ‘V’ type.
Position of tube holes Allowed through welded
seams, if they are
radiographed and stress
relieved. The ligament
efficiency shall be multiplied
by a factor 0.95.
Any type of opening that
meets the requirements for
compensation may be
located in a welded joint.
Machining of holes through
the centre of main seam
welds is permitted provided
the seam welds have been
subjected to NDE.
-----
Circularity of Drum Difference between internal
diameter of drum shall not
exceed 1%.
The drum shall be circular
within a limit of 1% of mean
diameter based on the
differences between
maximum and minimum
mean diameters.
Maximum internal diameter
of drum shall not exceed the
nominal internal diameter by
more than 2%.
The average bore shall not
deviate by more than 1%
from the nominal diameter.
Percentage deviation from
circularity
2 (d max.  d min.)
X 100
d max. + d min.
D max.  D min.
X 100
DS
D max.  D min.
X 100
DS
2 (d max.  d min.)
X 100
d max. + d min.
Hand hole size in Headers 89 x 63.5 89 x 70 ----- ------
DRUM / HEADERS - COMPARISON WITH VARIOUS CODES

28. DESCRIPTION IBR ASME SEC.I BS 1113 DIN TRD 300
Hydraulic test point - Shop
& test pressure.
Drums & Headers greater
than 1000 mm shall be
hydraulic tested at shop to
1.5 times the Design
Pressure.
----- Drums & Headers greater
than 600 mm shall be
hydraulic tested at shop to
1.5 times the max.
permissible working
pressure.
-----
Wall thickness tolerance for
pipes / headers.
+ 15%
 5%
 12.5% + 10%
 10%
+ 12.5%
 10.0%
Hydraulic test pressure at
site.
1.5 times the Drum Design
Pressure.
1.5 times the maximum
allowable Working
Pressure.
1.5 times the maximum
permissible Working
Pressure.
1.3 times the maximum
allowable Working
Pressure.
Requirement of Safety
Valves.
Two safety valves - the bore
not less than 19mm.
Two or more safety valves. Two safety valves.
Minimum bore 20 mm.
Two or more safety valves.
Water level indication. Two means of indicating
water leve.
Two numbers of gauge
glass. Two independent
remote level indicators
instead of one gauge glass.
Two independent means of
water level indication.
Two means of indicating
water level.

29. DESCRIPTION IBR ASME SEC.I BS 1113 DIN TRD 300
TYPE Cold drawn or hot
finished seamless or
ERW
Cold drawn or hot
finished seamless
or ERW
Cold drawn or hot
finished seamless or
ERW
Cold drawn or hot
finished seamless or
Longitudinally
welded
Minimum thickness
allowed for various
tube Diameters -
Seamless.
Up to D32 - 2.03
Up to D51 - 2.34
D51 to D76 - 2.64
D76 to D89 - 3.25
D89 to D114 - 3.66
Up to D32 - 2.41
Up to D51 - 2.67
D51 to D76 - 3.05
D76 to D102 - 3.43
D102 to D127 - 3.81
Up to D38 - 1.7
D38 to D51 - 2.2
D51 to D70 - 2.4
D70 to D76 - 2.6
D76 to D95 - 3.0
D95 to D102 - 3.3
D102 to D127 - 3.5
Min. - 3 mm
Max. - 6.3 mm
for Water wall tubes
Ovality
(Deviation from
circularity)
D Max.  D Min.
x 100
D
shall not exceed
20D
R
D  D Min.
x 100
D
shall not be more
than 50D
%
R
2(DMax.DMin.)
x100
DMax + DMin
Provides calculation
for wall thickness
for inside & outside
of bend as per
TRD301 Annex-2.
Wall thickness
tolerance
+ 10%
 5%
+ 22%
 0%
+ 10%
 10%
+ 15%
 10%
TUBES - COMPARISON WITH VARIOUS CODES

30. Sl.
No
Material
Specn.
Design
Temp. C
Allowable Stress
Kg/mm2
% increase
in
allowable
Stress
Correspond
-ing
in allowable
Stress
ASME BS 1113
01. Water Walls SA210
Gr.C
385 11.038 13.228 19.8 11.4
02. Downcomers SA106
Gr.C
357 11.993 13.570 13.0 9.8
03 Riser Pipes SA106
Gr.B
357 10.339 11.859 14.7 9.8
04. Economiser SA210
A1
311 10.546 12.896 22.3 16.0
05. Low temp.
SH
SA210
A1
373 10.087 12.442 23.7 17.6
Item
RELATIONSHIP BETWEEN ALLOWABLE STRESS, WEIGHT
AND SAVINGS IN WEIGHT
(TYPICAL 250 MW)

31. a) Circularity of drum 243 (a)256 (b)
b) Drawing preparation 249
c) Type of weld joint 253
d) Long seam intersection 254
E )Position of tube holes 255
f) Hydro Test 268
g) Maximum working pressure for shell 270
h) Stress factors 271
I )Ligament efficiency 272 (215)
j) Longitudinal stress 273
K Shape of Dished end plate 275
l) Dished end with openings 277
M) Dished end maximum working pressure 278
n) Reinforcement calculation 279
o) Attachment of Branch pipes 280
p) Mountings on the drum 281
q) Attachment (SV) to dru 296
r) Water gauges 320
s) Uncompensated hole 187
I) DRUM
IBR REGULATIONS

32. a) Header shapes and Process 154 (a)
b) Hand holes 164 (a)
c) Uncompensated hole 187
d) Maximum working pressure 270
e) Stress factors 271
f) Ligament efficiency 272 (215)
g) Shape of Dished end 275
h) Dished end opening 277
i) Dished end maximum working pressure 278
j) Reinforcement calculation 279
k) Attachment of Branch pipes 280
l) Flat ends maximum working pressure 340 (f)
m) Headers for boiler & SH 342
II) HEADERS

33. a) Process 151 (a), (b), (c)
b) Tubes 244 (a)
c) Maximum working pressure 338 (a)
d) Percentage ovality 338 (b), (c)
a) Integral boiler piping 244 (b)
b) Process 343 (1)
c) Material, permissible stress 343 (2)
d) Hydraulic Test 343 (3)
e) Temperature limits for Pipes, Tees, Branches 349
f) Maximum working pressure 350
g) Steam pipe bending thinning 361 (a)
h) Butt welding fittings 361 (A)
i) Branch welded to pipes 249 to 253
j) External Reinforcement 362 (b)
k) Hydraulic Test 374
III) TUBES
IV) LINES & LINKS (BOILER INTEGRAL PIPING)

34. a) Discharge capacity 293
b) Over pressure of safety valve 294
c) Pressure drop 295
d) Attachment to boiler 296
1) Procedure of Hydro test of boiler 379
2) Registration Fee 385
3) Submission of plans of boilers 393
4) Submission of plans of steam pipes 395
a) Requirements 320 a, b.
V) BOILER MOUNTINGS
A. SAFETY VALVES
B. WATER GUAGES
VI) GENERAL

35. BOILER & SH TUBES
Regn. 151: Tubes Cold drawn or hot finished
a) Seamless or ERW tubes
b) Tubes < 5” dia - can be used inside the boiler
> 5” dia - can be used outside the boiler
c) Flash welding allowed.
HEADERS MUD BOXES, ETC. OF WATER TUBE BOILERS
Regn. 154:
a) Headers Seamless or Welded steel or cast steel.
i) Where welded, the welding shall be stress relieved, radiographed or
UT.
ii) Headers may be closed by forging, bolting, screening or welding.
IBR

36. MAIN HOLES
Regn. 164 (a): Hole size not less than 3½ x 2½ in.
PD
Regn. 187: Uncompensated hole - Maximum 203 mm =
1.82 fe
FUSION WELDED DRUMS
Regn. 244 (a): Tubes
Regn.244 (b): Pipes of boiler shall comply with Chapter VIII.
Regn.243 (a): Circularity of drum 1%.
2 (d max.  d min.)
Regn. 243 (b): Percentage deviation = x 100
from circularity (d max. + d min.)
d = internal dia
Regn. 249: Fully dimensioned sectional drawing showing in full
detail the construction of drum - Fully dimensioned
drawings of the proposed weld preparation of the main
seams to a scale - attachment, seatings, etc. to be
furnished.

37. Regn. 253: Drum - type of welded joint - Single or double ‘U’ or
‘V’ type.
Regn. 254: Longitudinal seams in successive rigs shall not fall
in line except where the rigs of drum are in two
halves of unequal thickness.
Regn. 255: Position of tube holes:-
Tube holes through welded seams, if they are
radiographed and stress relieved - The efficiency
and ligament multiplied by a factor 0.95 except the
distance from edge hole to edge of weld > 13mm
(½”).
Regn. 256: Circularity of drum:-
The difference between internal diameter of drum
shall not exceed 1%.
Regn. 268: Hydro test - 1½ times the maximum permissible
working pressure after completion of welding and
heat treatment of drum (internal dia > 1000 mm).

38. 2 f E (T  0.03)
Regn.270: The working pressure - WP =
D + T  0.03
Weld factor 0.95.
Regn. 271: For temperature at or below 454C
E t R
(or)
1.5 2.7
For temperature above 454C
E t SR
(or) (or) SC
1.5 1.5
In case SC valves are not available, the allowable stress may be
E t SR
lower of (or)
1.5 1.5
Regn. 272: The ligament efficiency as per Regn. 215.
P  d P  nd P P1
Diagonal and Curve
P P d P
Circumferential ligament.

39. PD2
Regn. 273: Longitudinal Stress = fd =
1.273A
PD2
M =
1.273
MRY
The stress due to bending f b =
Ia
Regn. 275: Shape of Dished end plate
a) Hemispherical
b) Elliptical heads -H  0.2D
c) Partial spherical heads - H  0.18D.
Figures 23A, B, C.

40. Regn. 276: Gradual thinning up to a maximum of 10% of thickness
where the corner radius joins the dishing radius.
Regn. 277: Dished end with opening (inline with ISO).
d A
d1 = d 
DT T
Regn. 278: Dished end plate maximum working pressure
2f (T  C)
WP =
DK (Shape factor)
Minimum head thickness - 5 mm.
Regn. 279: Reinforcement calculation.
Regn. 280: Attachments of Branch Pipes by welding.
Figures 24A to D, 26A to E, 27A to D.

41. VALVES, GAUGES AND AUXILIARIES
Regn. 281: Every boiler shall be provided.
Two safety valves - one of which may be a high steam
and low water type, the bore not less than 19mm.
Two means of indicating water level.
a steam pressure gauge.
a steam stop valve.
a feed check valve.
one feed apparatus.
A blow down cock valve.
A manhole - A safety valve at the end of SH outlet.

42. New Regn.281A: Water level and or firing control.
SAFETY VALVES
Regn. 293: Discharge capacity.
Saturated steam E = CAP
E
Superheat steam ES =
1 + 2.7 TS
1000
Regn. 294: Over pressure of safety valves:
Where discharge area < 80% - Over pressure shall not exceed
10% of set pressure.
Where discharge area > 80% - Over pressure shall not exceed
5%.

43. Regn. 295: Pressure drop:
Reset at a pressure at least 2.5 below but not more than
5% below safety valve set pressure. The 5% limit
increased to 10% for valves having seat bore less than 32
mm and or having a set pressure of 2 bar gauge or less.
Regn. 296: Attachment to Boiler:
The axis valve shall be vertical. Branches shall be as short
as possible.
Regn. 320: Water Gauges:
Every boiler shall have two means of indicating the water
in it of which one shall be conventional gauge glass.
Minimum length of visible portion of gauge glass 200 mm.
b) For boilers > 10,000 lb/hr., one of water gauges may be of
remote water level indicator type.

44. BOILER AND SH TUBES, HEADERS
Regn. 338(a): 2f (T  C) C = 0.75 for P  70 Kg/m2
WP =
(D  T + C) = 0 for P > 70 Kg/m2
The working metal temperature.
ECO = The maximum water temperature + 11C.
Furnace & boiler tubes = Sat. temperature + 28C.
Convection SH =Maximum steam temperature + 39C.
Radiant SH = Maximum steam temperature + 50C.

45. For temperature at or below 454C.
TS Et
(or)
2.7 1.5
For temperature above 454C
SR or SC
1.5
If SC not available
E t SR
(or)
1.5 1.5
b) % Ovality = D max.  D min.
x 100
D

46. Regn. 340 (f): Flat ends for headers -
f (t  C)2
WP =
d2 K
Regn. 342: Cylindrical headers - As per Regn. 270.
End attachments - As per Regn. 340(f).
STEAM PIPES AND FITTINGS
Regn.343(1): Carbon steel, Cast steel, Alloy steel, cold or hot
finished, butt welded or ERW.
Regn. 343(2): Material used, the permissible stress figures
specified in the code may be accepted.

47. Regn. 343(3): The hydraulic test may be dispensed with if id 
600 mm.
Regn. 349: The temperature limits for pipes, Tees, branches,
etc. shall be as per Table-2.
Regn. 350: Working Pressure.
2fe (t  C)
WP = C = 0.75.
D  t + C
STEAM PIPE FITTINGS
Regn. 361(a): Pipe bends thinning 12.5%.
Regn. 361(A): Butt welding fittings.
Regn. 362(a): Branch welded to pipe Regn. 249 to 253. Angle not
less than 60.
Regn. 362(b): External Reinforcement :
Multiple radial plates of horse shoe form or the form
of collars applied to or around the junction between
branch and main.

48. Regn. 374: Hydro test pressure in the piping system - 1.5 times the
design pressure.
REGULATIONS FOR THE REGISTRATION AND INSPECTION OF BOILERS
Regn. 379: Procedure of Hydro test.
Test pressure 1.5 times the maximum working pressure.
Temperature of water > 20 < 50C.
Not exceeding 6% of the required pressure.
Regn. 385: Registration Fee:
Regn. 393: Submission of plans of boilers:
a) Drawing Approval.
b) & c) Boilers made outside India, Technical Advisor (Boilers)
and then CIB user state.

49. d) Scrutiny fees as per Regn. 385 subject to a
maximum of Rs. 20,000.
Alteration fee at 10% of the fee of the first
scrutiny fee.
Regn. 395: Submission of plans of steam pipes:
Rs. 30 for 30 meters minimum of Rs. 50.
Fittings like DESH, Separators, etc. Rs. 150
each.

50. Sl.No
.
DESCRIPTION CLAUSE REQUIREMENT AS PER ASME SEC.I 2001 REMARKS
1. Service
Limitations
PG-2 a)Boilers in which steam/vapour is
generated at a pr. more than 15 PSIG
b)High temp. water boilers > 160 PSIG or
250 Deg.F
2. Plate material PG-6 Shall be of pressure vessel quality SA202;
SA204; SA240(Type 405 only) SA302;
387(A.S) SA285; SA299; SA515; SA516
(C.S), SA / EN - 10028 - 2
3. Pipes, Tubes
materials
PG-9 PG 9.1 for boiler parts materials
PG 9.1 & 9.2 for superheater matrials
4. Boiler plate
min.thick
PG-16.3 The min. thickness of any boiler plate
under pressure shall be 1/4 in (6 mm)
5. Tubing calculation PG-27.2.1 "Upto and including 5 inches outside dia"
(127mm) t(inch)=PD/2S+P +0.005D+e
e = 0 for tubes strength welded to headers
P = Max. allowable working pressure(psi)
D = Outside dia(in)
S = Max. allowable stress (psi)

51. Sl.No
.
DESCRIPTION CLAUSE REQUIREMENT AS PER ASME SEC.I
2001
REMARKS
6. Piping, Drums
and headers
calculation
PG-
27.2.2
t =PD / 2SE+2YP + C (or) t = PR / SE -
(1-y)P+ C E = efficiency of
liagament of weld joints
Y = temperature co-efficient
C = Min. allowance for threading and
structural stability (0)
R = Inside radius in
7. Hemispherical
head
PG-29.11 t = PL / 1.6S
L = radius to which formed head
measured on concave side
8. 2:1 Semi-
ellipsoidal
PG-29.7
&
PG-
27.2.2
t = PR / SE - (1-y)P + C
R = Inside radius of end cover
9. Max. Dia of
opening in shell
PG-
32.1.2
&
PG-32.1.3.2
K Factor = PD / 1.82 St
Max. dia of opening without
compensation as per Fig PG 32
10. Compensation
Calulation
PG - 37
& PW -
15
Limits of reinforcement
X = greater of 2d or 2(t + tn) but not
greater than pitch Y = the smaller of 2
1/2t or 2 1/2 tn

52. Sl.No. DESCRIPTION CLAUSE REQUIREMENT AS PER ASME SEC.I 2001 REMARKS
11. Max. allowable
stress for drum
(Bending and Longi
stress)
PG - 22 &
Sec.3.3.4
of BS-
1113
Total stress = fb + fd
fb = stress due to bending
fd = Direct longitudinal stress
12. Hydraulic test pr. PG 99.1 1.5 times the max. allowable working pr.
Calculate stress at hydraulic test by
substituting in thick formula.Stress at
hydro to be leser than 90% yield stress at
100 deg. F.
13. Min. weld size PW - 16.1 Check as per Fig. PW 16.1
14. Min. weld size PG - 37
PW - 15
Combined strength of each path >min. weld
strength required
15. Feed water
connection
PG - 59.2 Boiler pr. 400 PSI or over the feed water
inlet shall be fitted with sleeves.
16. Blow - off PG -
59.3.3
Boiler shall have a bottom blow off outlet in
the lowest water space.
17. Water level
indicator
PG -
60.1.1
a) Two nos. gauge glass over a boiler pr. Of 400 PSI
b) Two independent remote level indicators instead
of one gauge glass in case of pr. above 900 PSI
c) The lowest visible part of gauge shall be at least
2 in. above lowest water level

53. Sl.No
.
DESCRIPTION CLAUSE REQUIREMENT AS PER ASME SEC.I
2001
REMARKS
18. Water level
indicator
PG -
60.1.6
a) Connection to the gauge glass shall
not be less than 1/2" pipe size
b) Water gauge glass drain not less
than 1/4 in. Above 100 PSI pr. Drain
connects to safe discharge point
19. Pressure gauges PG -
60.6.1
Pr. Gauge connection to the boiler
shall not be less than 1/2 in. Inside dia.
for steel pipe.
20. Test pr. Gauges PG-
60.6.3
Connection to the test pr. gauge shall
be at least 1/4 in. pipe size
21. Feed water
supply
PG-61 a)Boiler having more than 500 sq. ft. of
water heating surface shall have two
means of feeding water b) The
feed connection shall not be less than
3/4" pipe size for water heating surface
more than 100 sq. ft.

54. Sl.No
.
DESCRIPTION CLAUSE REQUIREMENT AS PER ASME SEC.I
2001
REMARKS
22. Boiler safety valve
reqts
PG-67.1 Boiler with water heating surface
exceeding 500 sq. ft. and steam
generating capacity exceeding 4000 lb/hr
two or more safety valves are required.
PG-67.3 a) one or more safety valves shall be set
at or below max. allowable working pr.
B)The highest pr. Setting shall not
exceed 3% of the max. allowable working
pressure
PG - 67.2 c) The safety valve will discharge all the
steam generated by the boiler without
allowing the pr. to rise more than 6%
above max. allowable working pressure.
PG-68.2 The discharge capacity of the safety
valve on the boiler is at least 75% of the
aggregate value capacity required
23. Drain, vents
provisions
PG -
58.3.7
Piping connections for items such as
drains, vents for a high temp. Boiler.

55. 2..1.2 MATERIALS FOR PP.
BS MATERIALS OR AGREED BETWEEN MANUFACTURER AND
PURCHASER
2.2 DESIGN STRESSES
2.2.3 FOR C, C-Mn AND LOW ALLOY STEELS
FE = Re (T)/1.5 OR Rm /2.7 WHICHEVER GIVES A LOWER
VALUE.
2.2.4 FOR AUSTENTIC STEEL
FE = Re (T)/1.35 OR Rm /2.7 WHICHEVER GIVES A LOWER
VALUE.
SALIENT CLAUSES OF BS-1113-1990
SECTION –2 MATERIALS AND DESIGN STRESSES

56. 2.2.7 DESIGN TEMPERATURE
2.2.7.1 DRUMS AND HEADERS
NOT HEATED BY GAS - EQUALS FLUID TEMP.
HEATED BY GAS - ADD 25  C.
2.2.7.2 BOILER TUBES
SUBJECT TO RADIANT HEAT -- SAT TEMP. + 50  C.
NOT SUBJECT TO RADIANT HEAT -- SAT TEMP. + 25  C.
2.2.7.3 SH & RH TUBES
SUBJECT TO RADIANT HEAT -- SAT TEMP. + 50  C.
NOT SUBJECT TO RADIANT HEAT -- SAT TEMP. + 35  C.
2.2.7.4 ECONOMIZER TUBES
MAX FLUID TEMP + 25  C.

57. SECTION –3 DESIGN
3.3.4 COMBINED STRESSES IN DRUMS AND HEADERS.
TO BE BROUGHT IN PLACE OF REG.73 OF IBR
3.3.1 MINIMUM 9.5 mm THICK FOR HEADERS OF OD 300 mm AND
ABOVE.
3.3.2 MINIMUM 6 mm THICK FOR HEADERS UPTO OD 300 mm
t = PDi / 2 f n - P
3.3.3.1. MAX DIA OF UNREINFORCED OPENING 200 mm.
3.6.1 DISHED ENDS
TORI AND SEMI ELLIPSOIDAL DISHED ENDS.
3.6.1.2 t= PDOK/2f
MINIMUM THICKNESS OF DISHED ENDS TO BE 9.5 mm.

58. 3.6.1.3.1 UNREINFORCED OPENINGS
OPENINGS NOT TO BE GIVEN IN D/10
AREA.
3.7.2 TUBES AND PIPES
3.7.2.1 t = P do/2f + P.
MINIMUM THICKNESS TO AS UNDER
UPTO 38 MM OD 1.7
38 TO 51 MM OD 2.2
51 TO 70 MM OD 2.4
70 TO 76 MM OD 2.6
76 TO 95 MM OD 3.0
95 TO 102 MM OD 3.3
102 TO 127 MM OD 3.5

59. SECTION 4 MANUFACTURE AND WORKMANSHIP
4.2.2.5.1 PLATES CAN BE BUTT WELDED PRIOR TO
FORMING PROVIDED WELD IS NDT EXAMINED.
4.2.2.5.2 OUT OF ROUNDNESS NOT TO EXCEED 1 % OF
NOM INTERNAL DIA.
4.3.1.1.6 LONGITUDINAL DRUM SEAMS TO BE WELDED
BEFORE CIRCUMFERENTIAL SEAMS AND WHRE
PRACTICABLE THE LONGITUDINAL SEAMS OF
ADJACENT COURSES SHALL BE STAGGERED.
4.3.1.1.7 HOLES CAN BE MACHINED THROUGH THE SEAMS
AFTER SEAM HAS BEEN NDT EXAMINE PRIOR TO
PWHT.

60. SECTION 5 INSPECTION AND TESTING
5.10.1.1 HYDROSTATIC TEST PRESSURE
5.10.2.1 HYDRO TEST PRESSURE OF BOILER 1.5 TIMES
THE MAX WORKING PRESSURE.
DRUMS AND CYLINDRICAL HEADERS GREATER
THAN 600 MM SHALL BE HYDROSTATICALLY
TESTED AT SHOP.
5.10.3.1 ALL COMPONENTS NOT REASONABLY
ACESSIBLE TO INSPECTION AFTER ASSEMBLY
TO BE HYDROTESTED AT SHOP.

61. SECTION 7 VALVES, GUAGES AND FITTINGS
7.2 SAFETY VALVES
7.2.1.1 MINIMUM BORE 20 mm
7.2.1.2 FOR EVAPOTATION UPTO 3700 KG/H ONE
SAFETY VALVE FOR GREATER
EVAPORATION TWO SAFETY VALVES
7.2 WATER LEVEL GUAGE
EACH BOILER TO HAVE TWO INDEPENDENT
MEANS OF WATER LEVEL INDICATION.

62. Sl.No. Description BHEL MBEL
01. BOILER DRUM - Shell
Material
Thickness in mm
Internals
CARBON STEEL to SA299
195 / 165
Turbo Separators (92 Nos)
ALLOY STEEL to Specification BS
EN 10028-2 1993 Grade NC 271
111/111
Cyclone Separators (168 Nos)
02. DOWNCOMERS 6 Nos. of D368 SA106 Gr.C 4 Nos. of D508 BS 3602 500Nb -
Supply pipes - 48 Nos. of D139.7
03. WATERWALLS D51 at 63.5 Centres Rifled -
SA210 Gr.C
Tangential firing.
D66.7 at 92 Centres Rifled - BS
3059 243 S2 Calls for optimisation
with headers.
Front / Rear wall firing.
04. RISERS 68 Nos. of D159 - SA106 Gr.C
Risers are connected to the
top of drum.
48 Nos. of D168.3 - BS 3602 500 Nb
The rear and bottom of drum.
05. PRIMARY
SUPERHEATER
Strap type support with
hanger tubes.
SA240 Type 310/304.
Armchair support with hanger
tubes.
BS 1563 - 620 - 440.
BOILER PRESSURE PARTS
COMPARISON BETWEEN BHEL & MBEL (500 MW) Page 01 of 02

63. Page 02 of 02
Sl.No. Description BHEL MBEL
06. PLATEN SH / FINAL SH Flex connectors for spacing
between tubes.
Tangent Flex tie at close spacings.
Common Header for inlet & outlet of
all assemblies.
Wraparounds for spacing between tubes.
Only 2 DAGS of Material BS 3059 622 S2 &
T91 - Half the horizontal bottom portion of
platen membraned.
Individual headers for both inlet & outlet of
each Coil Assembly (Calls for
optimisation).
07. REHEATER Front RH - Flex connectors for
spacing.
Rear RH - Alignment band for
spacing.
Tube strap support for both Front &
Rear Reheater.
08. ECONOMISER Two loop D51 - SA210 Gr.A1 Not covered in the scope.
09. ATTEMPERATOR Liner is positioned with shell
support screws.
Liner is positioned with shell by support
bar welded to liner out side and support
ring.
10. STEAM COOLED
WALLS
D63.5 / D51 at 152.4 Centres -
SA210 Gr.C
D44.5 at 115 Centres - BS 3059 243 S2.

64. COST SAVINGS DUE TO NEW MATERIALS
Sl.
No
.
Pipe / Tube
Specification
Usage
Area
Annual
Quantum
(2003-
04)
Tons
Cost/T
on
Total
Cost
Increase
Substitute
d
Material
Cost
Savings

(%)
Total
Savings
(in
Crores)
01. SA106 Gr.B /
Gr.C
Water wall
Headers,
Downcomers,
Risers
2000 70,000 14 WB361 25% 3.5
02. SA213 T22 SH / RH
coils
1060 60,000 6.36 SA213
T232
23% 1.46
03. SA213 T91 SH / RH
coils
257 1,30,00
0
3.34 SA213
T922
21% 0.7
04. SA213 TP347
H
SH / RH
coils
173 2,10,00
0
3.63 SA213
T922
21% 0.76
TOTAL SAVINGS / YEAR 6.42
 Cost Savings projected by M/s. V&M.
1 = Code case but covered in DIN.
2 = Published in ASME.