ASTM A335
Seamless ferritic alloy steel (P-grade) pipe for high-temperature service
Covers seamless ferritic alloy steel pipe for high-temperature service — the chrome-moly "P" grades such as P5, P9, P11, P22 and P91.
- Pipe & tube
- ASME SA-335
- 2 grades in stock range
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What to know before ordering to ASTM A335
The points that decide whether material to ASTM A335 is accepted at inspection.
- P11 (1¼Cr-½Mo) and P22 (2¼Cr-1Mo) are the common grades for steam and hot-oil lines.
- Matching fittings are ASTM A234 WP11 / WP22 and flanges ASTM A182 F11 / F22.
- Post-weld heat treatment requirements come from the design code, not A335.
Grades and products we supply to ASTM A335
| Grade | Product | Designation on the certificate |
|---|---|---|
| ASTM A335 P11 | Pipe & Tube | ASTM A335 P11 |
| ASTM A335 P22 | Pipe & Tube | ASTM A335 P22 |
How ASTM A335 fits into an order
A purchase order line is only complete when it names the material standard, the dimensional standard and the inspection document. Miss one and the mill, the inspector and the buyer can each read the order differently.
Related standards
ASTM A335 — questions buyers ask
What does ASTM A335 cover?
Covers seamless ferritic alloy steel pipe for high-temperature service — the chrome-moly "P" grades such as P5, P9, P11, P22 and P91.
Which grades do you supply to ASTM A335?
ASTM A335 P11, ASTM A335 P22 — see the table on this page for the exact product and designation.
What is the difference between ASTM A335 and ASME SA-335?
ASME SA-335 is the ASME Boiler and Pressure Vessel Code (Section II) adoption of ASTM A335. The technical requirements are usually identical to a specific ASTM edition; pressure-equipment codes call for the ASME designation, and most mill certificates show both.
Do you supply certificates to this standard?
Yes. Material is supplied with mill test certificates to EN 10204 3.1 showing the standard, grade and heat number; 3.2 with third-party inspection on request.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026