 |
Reg. 53 a
MATERIALS OF CONSTRUCTION
SEAMLESS FERRITIC PIPES FOR HIGH TEMPERATURE
SERVICE
Material
|
(i) The pipes shall
be seamless and manufactured from steel produced by an open hearth
or electric process or any of the Oxygen processes.
The steel shall be fully killed.
(ii) The steel shall conform to the limits of chemical composition
as given in table-4.
Table
4
CHEMICAL
REQUIREMENTS FOR FERRITIC STEELS
|
Grade
|
Chemical
composition %
|
|
|
C
|
Mn
|
Si
|
S
|
P
|
Cr
|
Mo
|
V
|
Ni
|
Other
Elements
|
|
P1
|
0.10
0.20
|
0.30
0.80
|
0.10
0.50
|
0.025
max
|
0.025
max
|
----
|
0.44
0.65
|
----
|
----
|
-----
|
|
P2
|
0.10
0.20
|
0.30
0.61
|
0.10
0.30
|
0.025
max
|
0.025
max
|
0.50
0.81
|
0.44
0.65
|
----
|
----
|
-----
|
|
P5
|
0.15
max
|
0.30
0.60
|
0.50
max
|
0.025
max
|
0.025
max
|
4.00
6.00
|
o.45
0.65
|
----
|
----
|
-----
|
|
P9
|
0.15
max
|
0.30
0.60
|
0.25
1.00
|
0.025
max
|
0.025
max
|
8.00
10.0
|
0.90
1.10
|
----
|
----
|
-----
|
|
P11
|
0.05
0.15
|
0.30
0.60
|
0.50
1.00
|
0.025
max
|
0.025
max
|
1.00
1.50
|
0.44
0.65
|
----
|
----
|
-----
|
|
P12
|
0.05
0.15
|
0.30
0.61
|
0.50
max
|
0.025
max
|
0.025
max
|
0.80
1.25
|
0.44
0.65
|
----
|
----
|
-----
|
|
P22
|
0.05
0.15
|
0.30
0.60
|
0.50
max
|
0.025
max
|
0.025
max
|
1.90
2.60
|
0.87
1.13
|
----
|
----
|
-----
|
|
P91
|
0.08
0.12
|
0.30
0.60
|
0.20
0.50
|
0.010
max
|
0.020
max
|
8.00
9.50
|
0.85
1.05
|
0.18
0.25
|
----
|
Nb=0.06
- 0.10
N=0.030
- 0.70
Ni=0.40
max
Al=0.04
max
|
|
X20Cr
MoV121
|
0.17
0.23
|
1.00
max
|
0.50
max
|
0.03
max
|
0.030
max
|
10.0
12.5
|
0.80
1.20
|
0.25
0.35
|
0.30
0.80
|
----
|
|
