Abstract
This specification covers seamless ferritic alloy-steel pipe for high-temperature service. The pipe shall be suitable for bending, flanging (vanstoning), and similar forming operations, and for fusion welding. Grade P2 and P12 steel pipes shall be made by coarse-grain melting practice. The steel material shall conform to chemical composition, tensile property, and hardness requirements. Each length of pipe shall be subjected to the hydrostatic test. Also, each pipe shall be examined by a non-destructive examination method in accordance to the required practices. The range of pipe sizes that may be examined by each method shall be subjected to the limitations in the scope of the respective practices. The different mechanical test requirements for pipes, namely, transverse or longitudinal tension test, flattening test, and hardness or bend test are presented.
Scope
1.1 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. Selection will depend upon design, service conditions, mechanical properties, and high-temperature characteristics.
1.2 Several grades of ferritic steels (see Note 1) are covered. Their compositions are given in Table 1.
Note 1—Ferritic steels in this specification are defined as low- and intermediate-alloy steels containing up to and including 10 % chromium.
1.3 Supplementary requirements (S1 to S7) of an optional nature are provided. These supplementary requirements call for additional tests to be made, and when desired, shall be so stated in the order together with the number of such tests required.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. The inch-pound units shall apply unless the “M” designation of this specification is specified in the order.
Note 2—The dimensionless designator NPS (nominal pipe size) has been substituted in this standard for such traditional terms as “nominal diameter,” “size,” and “nominal size.”
TABLE 1 Chemical Requirements
| Grade | UNS Designa- tionA | Composition, % | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Carbon | Man- ganese | Phos- phorus, max | Sulfur, max | Silicon | Chromium | Molybde- num | Others | ||
| P1 | K11522 | 0.10–0.20 | 0.30–0.80 | 0.025 | 0.025 | 0.10–0.50 | . . . | 0.44–0.65 | . . . |
| P2 | K11547 | 0.10–0.20 | 0.30–0.61 | 0.025 | 0.025 | 0.10–0.30 | 0.50–0.81 | 0.44–0.65 | . . . |
| P5 | K41545 | 0.15 max | 0.30–0.60 | 0.025 | 0.025 | 0.50 max | 4.00–6.00 | 0.45–0.65 | . . . |
| P5b | K51545 | 0.15 max | 0.30–0.60 | 0.025 | 0.025 | 1.00–2.00 | 4.00–6.00 | 0.45–0.65 | . . . |
| P5c | K41245 | 0.12 max | 0.30–0.60 | 0.025 | 0.025 | 0.50 max | 4.00–6.00 | 0.45–0.65 | . . .B |
| P9 | S50400 | 0.15 max | 0.30–0.60 | 0.025 | 0.025 | 0.25–1.00 | 8.00–10.00 | 0.90–1.10 | . . . |
| P11 | K11597 | 0.05–0.15 | 0.30–0.60 | 0.025 | 0.025 | 0.50–1.00 | 1.00–1.50 | 0.44–0.65 | . . . |
| P12 | K11562 | 0.05–0.15 | 0.30–0.61 | 0.025 | 0.025 | 0.50 max | 0.80–1.25 | 0.44–0.65 | . . . |
| P15 | K11578 | 0.05–0.15 | 0.30–0.60 | 0.025 | 0.025 | 1.15–1.65 | . . . | 0.44–0.65 | . . . |
| P21 | K31545 | 0.05–0.15 | 0.30–0.60 | 0.025 | 0.025 | 0.50 max | 2.65–3.35 | 0.80–1.06 | . . . |
| P22 | K21590 | 0.05–0.15 | 0.30–0.60 | 0.025 | 0.025 | 0.50 max | 1.90–2.60 | 0.87–1.13 | . . . |
| P23 | K41650 | 0.04–0.10 | 0.10–0.60 | 0.030 max | 0.010 max | 0.50 max | 1.90–2.60 | 0.05–0.30 | V 0.20–0.30 Cb 0.02–0.08 B 0.0010–0.006 N 0.015 max Al 0.030 max W 1.45–1.75 Ni 0.40 max Ti 0.005–0.060 Ti/N ≥ 3.5C |
| P24 | K30736 | 0.05–0.10 | 0.30–0.70 | 0.020 | 0.010 | 0.15–0.45 | 2.20–2.60 | 0.90–1.10 | V 0.20–0.30 Ti 0.06–0.10 N 0.012 max Al 0.02 max B 0.0015–0.007 |
| P36 | K21001 | 0.10–0.17 | 0.80–1.20 | 0.030 max | 0.025 max | 0.25–0.50 | 0.30 max | 0.25–0.50 | Ni 1.00-1.30 Cu 0.50-0.80 Cb 0.015-0.045 V 0.02 max N 0.02 max Al 0.050 max |
| P91 | K91560 | 0.08–0.12 | 0.30–0.60 | 0.020 | 0.010 | 0.20–0.50 | 8.00–9.50 | 0.85–1.05 | V 0.18–0.25 |
| N 0.030–0.070 | |||||||||
| Ni 0.40 max | |||||||||
| Al 0.02 max | |||||||||
| Cb 0.06–0.10 | |||||||||
| Ti 0.01 max | |||||||||
| Zr 0.01 max | |||||||||
| P92 | K92460 | 0.07–0.13 | 0.30–0.60 | 0.020 | 0.010 | 0.50 max | 8.50–9.50 | 0.30–0.60 | V 0.15–0.25 N 0.03–0.07 Ni 0.40 max Al 0.02 max Cb 0.04–0.09 W 1.5–2.00 B 0.001–0.006 Ti 0.01 max Zr 0.01 max |
| P122 | K92930 | 0.07–0.14 | 0.70 max | 0.020 | 0.010 | 0.50 max | 10.00–11.50 | 0.25–0.60 | V 0.15–0.30 W 1.50–2.50 Cu 0.30–1.70 Cb 0.04–0.10 B 0.0005–0.005 N 0.040–0.100 Ni 0.50 max Al 0.020 max Ti 0.01 max Zr 0.01 max |
| P911 | K91061 | 0.09–0.13 | 0.30–0.60 | 0.020 max | 0.010 max | 0.10–0.50 | 8.5–9.5 | 0.90–1.10 | V 0.18–0.25 Ni 0.40 max Cb 0.060–0.10 B 0.0003–0.006 N 0.04–0.09 Al 0.02 max W 0.90–1.10 Ti 0.01 max Zr 0.01 max |
A New designation established in accordance with Practice E527 and SAE J1086, Practice for Numbering Metals and Alloys (UNS).
B Grade P 5c shall have a titanium content of not less than 4 times the carbon content and not more than 0.70 %; or a columbium content of 8 to 10 times the carbon content.
C Alternatively, in lieu of this ratio minimum, the material shall have a minimum hardness of 275 HV in the hardened condition, defined as after austenitizing and cooling to room temperature but prior to tempering. Hardness testing shall be performed at mid-thickness of the product. Hardness test frequency shall be two samples of product per heat treatment lot and the hardness testing results shall be reported on the material test report.
