Overview
AH36, DH36 and EH36 belong to a 36-strength hull-steel group but differ in toughness designation and approved condition context. Their selection must be tied to the hull member, design temperature, thickness, delivery condition and class approval.
Designation and acceptance
IACS Unified Requirements are minimum classification-society requirements. Grade notation, thickness, delivery condition, test temperature, plate approval and the ship’s class rules must be read together; notation alone does not create an interchangeable material approval.
Members and selection
| Designation | Selection context |
|---|---|
| AH36 | 36-strength group notation selected only where the approved material schedule permits its toughness and condition. |
| DH36 | 36-strength group notation with distinct toughness/test context; check the member rule and thickness. |
| EH36 | 36-strength group notation for conditions requiring the specified toughness class; do not infer interchangeability from yield group alone. |
Comparison framework
| Criterion | Decision context |
|---|---|
| Selection basis | The 36-strength group does not remove the need to order the exact toughness designation and class-approved delivery condition. |
Performance
- AH36, DH36 and EH36 share a 36-strength family but carry different toughness designation contexts; yield group alone cannot approve a change between them.
Orderable product scope
- Shipbuilding plate, wide flat and sections must be quoted with class approval, grade notation, thickness, delivery condition, inspection and material certificates.
Processing
- For AH36/DH36/EH36 fabrication, qualify weld procedure, heat input, consumables, preheat/interpass controls, repair and NDT for the ordered thickness and delivery condition.
Applications
- Hull structural members and marine structures where the design, classification and fabrication documents approve the ordered steel.
Selection
- Select AH36, DH36 or EH36 from member criticality, design temperature, thickness and class schedule, then confirm mill approval and delivery route.
Procurement
- State the full AH36/DH36/EH36 designation, class rule, approved plate manufacturer, thickness range, normalized or thermomechanical condition where applicable, toughness testing and welding dossier.