AH36 vs DH36 vs EH36 vs FH36 Shipbuilding Steel Plate Comparison

AH36, DH36, EH36 and FH36 are high strength shipbuilding steel plates widely used for ship hulls and offshore structures. All four grades share the same minimum yield strength of 355 MPa, but differ significantly in low temperature impact toughness. This page provides a clear comparison to help engineers and buyers select the correct steel grade.

Overview of AH / DH / EH / FH Series

The letters A, D, E and F represent different impact test temperatures. As the letter level increases, the steel plate offers better resistance to brittle fracture in colder environments.

AH36 vs DH36 vs EH36 vs FH36 – Key Comparison Table

Steel Grade Minimum Yield Strength Impact Test Temperature Low Temperature Performance Typical Application
AH36 355 MPa 0°C Standard General ship hull structures
DH36 355 MPa -20°C Improved Cold region ships and marine structures
EH36 355 MPa -40°C Excellent Low temperature offshore platforms
FH36 355 MPa -60°C Ultra low temperature Arctic and polar marine environments

How to Choose the Right Shipbuilding Steel Grade

When selecting shipbuilding steel plates, the most important factor is the minimum design temperature of the vessel or structure. Choosing a steel grade with insufficient low temperature toughness may significantly increase the risk of brittle fracture.

  • AH36 is suitable for normal temperature marine environments.
  • DH36 is recommended for moderate cold regions.
  • EH36 is widely used in low temperature offshore engineering.
  • FH36 is designed for extreme cold, Arctic and ice-class vessels.

Classification Society Approval

All AH36, DH36, EH36 and FH36 steel plates can be supplied with approval from major classification societies, including: ABS, DNV, LR, BV, CCS, NK and KR.

Related Shipbuilding Steel Products

FAQ – Shipbuilding Steel Grade Comparison

1. What is the main difference between AH36 and DH36?

The main difference is the impact test temperature. AH36 is tested at 0°C, while DH36 is tested at -20°C.

2. Can EH36 replace DH36 or AH36?

Yes. EH36 provides better low temperature toughness and can replace DH36 or AH36 when required by design conditions.

3. Why is FH36 used in Arctic vessels?

FH36 offers ultra low temperature impact toughness tested at -60°C, making it suitable for extreme cold environments.

4. Do all grades have the same strength?

Yes. AH36, DH36, EH36 and FH36 all have a minimum yield strength of 355 MPa.