A537 Class 1
USApproximate matchASTM/ASME · ASTM A537/A537M (ASME SA-537)
Family of fine-grain, aluminum-killed carbon-manganese-silicon steel plates, normalized and Charpy-impact tested to guarantee good toughness at low temperature. Used for liquefied gas storage tanks, air separation units, LPG spheres and equipment exposed to sub-zero service temperatures (typically -20°C to -60°C), without requiring the nickel-alloy steels reserved for more extreme cryogenic applications.
| Grade | Region | Standard | Re (MPa) | Rm (MPa) | Delta |
|---|---|---|---|---|---|
| A537 Class 1 | US | ASTM A537/A537M (ASME SA-537) | 345 | 485–620 | reference |
| P355NL1 (n° matière 1.0566) | EU | EN 10028-3 | 355 | 490–630 | +3% |
| P355NL2 (n° matière 1.0577) | EU | EN 10028-3 | 355 | 490–630 | +3% |
| SLA360 | KR | KS D3541 | 360 | 490–610 | +4% |
| SLA325B | JP | JIS G3126 | 325 | 440–560 | -6% |
| SLA365 | JP | JIS G3126 | 365 | 490–610 | +6% |
| Neighboring grades — different strength | |||||
| A662 Grade C | US | ASTM A662/A662M | 295 | 480–620 | -14% |
| Grade | C | Mn | Si | P | S | Cr | Ni | Mo | Cu | Nb | V | Ti | N | Al |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A537 Class 1 | ≤0.24 | 0.7–1.6 | 0.15–0.5 | ≤0.025 | ≤0.025 | — | — | — | — | — | — | — | — | — |
| P355NL1 (n° matière 1.0566) | ≤0.18 | 1.1–1.7 | ≤0.5 | ≤0.025 | ≤0.008 | ≤0.3 | ≤0.5 | ≤0.08 | ≤0.3 | ≤0.05 | ≤0.1 | ≤0.03 | ≤0.012 | ≥0.02 |
| P355NL2 (n° matière 1.0577) | ≤0.18 | 1.1–1.7 | ≤0.5 | ≤0.02 | ≤0.005 | ≤0.3 | ≤0.5 | ≤0.08 | ≤0.3 | ≤0.05 | ≤0.1 | ≤0.03 | ≤0.012 | ≥0.02 |
| SLA360 | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| SLA325B | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| SLA365 | ≤0.18 | 0.8–1.6 | ≤0.55 | ≤0.025 | ≤0.02 | — | — | — | — | — | — | — | — | — |
| A662 Grade C | ≤0.24 | 0.79–1.62 | 0.13–0.45 | ≤0.035 | ≤0.035 | — | — | — | — | — | — | — | — | — |
Note: Important correction: the designations initially suggested for this family (ASTM A333 Gr.6 and ASTM A420) are NOT plate products — A333 Gr.6 is a seamless/welded PIPE standard for low-temperature service, and A420 (WPL6) is a forged/cast FITTINGS standard for low-temperature piping. They complement each other (pipe + fitting) but cover no flat product. The correct ASTM standard for low-temperature carbon steel PLATE for pressure vessels is ASTM A537 (normalized carbon-manganese-silicon plate) and/or ASTM A662 (see next grade), both directly comparable to the EN 10028-3 series (P355NL1/NL2) and JIS G3126 (SLA325/SLA365). A537 Class 1 is generally matched with JIS SLA325B and EN P355NL1.
Values compiled from public sources for guidance only — always verify against the official standard before use in design or fabrication.