 Alloy Steel Pipes & Tubes
This specification covers nominal wall and minimum wall seamless ferritic alloy-steel pipe intended for high temperature service. Pipe ordered to this specification shall be suitable for bending, flanging (vanstoning), and similar forming operations, and for fusion welding.
Heat Treatment
Grade
|
P5, P9, P11, and P22
Heat Treatment Type |
Normalizing Temperature Range F [C] |
Subcritical Annealing or Tempering Temperature Range F [C] |
| P5 (b,c) |
Full or Isothermal Anneal |
|
|
| |
Normalize and Temper
Subcritical Anneal (P5c only) |
*****
***** |
1250 [675]
1325 - 1375 [715 - 745] |
| P9 |
Full or Isothermal Anneal |
|
|
| |
Normalize and Temper |
***** |
1250 [675] |
| P11 |
Full or Isothermal Anneal |
|
|
| |
Normalize and Temper |
***** |
1200 [650] |
| P22 |
Full or Isothermal Anneal |
|
|
| |
Normalize and Temper |
***** |
1250 [675] |
| P91 |
Normalize and Temper
Quench and Temper |
1900-1975 [1040 - 1080]
1900-1975 [1040 - 1080]x |
1350-1470 [730 - 800]
1350-1470 [730 - 800] |
Chemical Requirements
| Element |
Grade |
P-5 |
P-9 |
P-11 |
P-22 |
P-91 |
P-91 shall also include the following: |
| UNS Designation |
K41545 |
S50400 |
K11597 |
K21590 |
K91560 |
| Carbon |
0.15 max |
0.15 max |
0.05 - 0.15 |
0.05 - 0.15 |
0.08 - 0.12 |
V at 0.18 - 0.25 |
| Manganese |
0.30 - 0.60 |
0.30 - 0.60 |
0.30 - 0.60 |
0.30 - 0.60 |
0.30 - 0.60 |
N at 0.030 - 0.070 |
| Phosphorous, max |
0.025 |
0.025 |
0.025 |
0.025 |
0.020 |
Ni at 0.40 max |
| Sulfur, max |
0.025 |
0.025 |
0.025 |
0.025 |
0.010 |
Al at 0.02 max |
| Silicon |
0.50 max |
0.25 - 1.00 |
0.50 - 1.00 |
0.50 max |
0.20 -0.50 |
Cb at 0.06 - 0.10 |
| Chromium |
4.00 - 6.00 |
8.00 - 10.00 |
1.00 - 1.50 |
1.90 - 2.60 |
8.00 - 9.50 |
Ti at 0.01 max |
| Molybdenum |
0.45 -0.65 |
0.90 - 1.10 |
0.44 - 0.65 |
0.87 - 1.13 |
0.85 - 1.05 |
Zr at 0.01 max |
|
