Welding Process for DNV Grade A Ordinary-Strength Shipbuilding Steel Plates
- Jun 06, 2026
Knowledge
Are ABS Grade B steel and ASTM A131 Grade B steel equivalent?
Having compared the chemical composition, mechanical properties and certification systems of ABS Grade B steel and ASTM A131 Grade B steel, we have concluded that:
a) For general structural applications where no classification society certification is required, the two materials are interchangeable.
b) For vessels or offshore installations requiring ABS classification, the materials cannot be simply interchanged; Grade B steel bearing ABS classification, a steel stamp and a certificate must be used. Materials produced solely in accordance with the relevant standards but lacking ABS certification will not be accepted by the classification society.
1. Comparison of Chemical Composition(heat analysis, wt %)
| Grade | C | Si | Mn | P | S | Cu | Cr | Ni |
|---|---|---|---|---|---|---|---|---|
| ABS Grade A | ≤ 0.21 | ≤ 0.35 | ≥ 0.80 | ≤ 0.035 | ≤ 0.035 | ≤ 0.35 | ≤ 0.30 | ≤ 0.30 |
| ASTM A131 B | ≤ 0.21 | ≤ 0.35 | ≥ 0.80 | ≤ 0.035 | ≤ 0.035 | ≤ 0.35 | ≤ 0.30 | ≤ 0.30 |
* The chemical composition is the same.
2. Comparison of Mechanical Properties
| Grade | Yield Strength (ReH), MPa | Tensile Strength (Rm), MPa | Elongation (A), % | Impact Energy (KV2 / J, at 0℃) | |
|---|---|---|---|---|---|
| Longitudinal | Transverse | ||||
| ABS Grade B | ≥ 235 | 400 - 520 | 22 | 27 | 20 |
| ASTM A131 Grade B | ≥ 235 | 400 - 520 | 22 | 27 | 20 |
* The mechanical properties are the same.
3. Comparison of Certification Systems (key differences)
| Grade | Standards / Certification | Difference |
|---|---|---|
| ABS Grade B | ABS | ASTM general material standards are used solely to verify that the chemical composition and mechanical properties of steel comply with the basic specification requirements. |
| ASTM A131 Grade B | ASTM A131/A131M | Specifications for ABS-certified special materials. Steel must be ABS-certified and undergo product testing, and must comply with the classification society’s additional quality control requirements, before it may be used in ships and offshore engineering projects recognised by ABS. |
Recent Article
Customers choose to engage in long-term cooperation with Yuxin Steel not only because of our high-quality products and services, as well as our strong reputation in the international market, but also due to our experienced one-stop raw material supply and further steel processing capabilities!
