Cr-Mo Alloy Steel Designation Chart (P / T / F / WP / Grade)
How the same chrome-moly chemistry is designated across ASTM A335 pipe, A213 tube, A387 plate, A182 forgings and A234 fittings: P1, P5, P9, P11, P22 and P91.
Cr-Mo Alloy Steel Designation Chart (P / T / F / WP / Grade)
| Chemistry | Pipe (A335) | Tube (A213) | Plate (A387) | Forging (A182) | Fitting (A234) |
|---|---|---|---|---|---|
| Carbon-½ molybdenum | A335 P1 | A213 T1 | — | A182 F1 | A234 WP1 |
| 5% chromium-½% molybdenum | A335 P5 | A213 T5 | A387 Grade 5 | A182 F5 | A234 WP5 |
| 9% chromium-1% molybdenum | A335 P9 | A213 T9 | A387 Grade 9 | A182 F9 | A234 WP9 |
| 1¼% chromium-½% molybdenum | A335 P11 | A213 T11 | A387 Grade 11 | A182 F11 | A234 WP11 |
| 2¼% chromium-1% molybdenum | A335 P22 | A213 T22 | A387 Grade 22 | A182 F22 | A234 WP22 |
| Modified 9% chromium-1% molybdenum-vanadium | A335 P91 | A213 T91 | A387 Grade 91 | A182 F91 | A234 WP91 |
Frequently asked questions
Where does this data come from?
From the specifications cited on each grade page (mostly ASTM / ASME). Values are specification limits or typical values, not heat-specific results.
Can I use this chart for material substitution?
Use it for screening only. Substitution must be approved against the governing specification and design code.
How do I get the full data for a grade?
Open the grade page for composition, mechanical properties, specifications by form, sizes and weight charts.
Need material to these grades?
Send grade, form, size and quantity.