Shipbuilding Steel Plates
EH36 / DH36 High-Strength Marine Steel Plate
Product Overview & Manufacturing Standard
EH36 / DH36 are high-strength hull structural steel plates manufactured to GB/T 712-2011 and ASTM A131/A131M. The grade designation is read as: E = Charpy impact test at -40°C, D = -20°C, H = high strength, 36 = minimum yield strength 355 MPa. Plates are supplied normalized (N) or thermomechanically rolled (TMCP), with heat-treatment condition and class endorsement stated on the mill certificate.
Typical thickness 6 mm – 150 mm (heavy plate), width up to 3,200 mm, length up to 12,000 mm. Z-direction quality (Z25 / Z35) and ultrasonic testing to class rules are available on request.
Class Society Approvals – 9 Societies
| Society | Classification Society | Grades Endorsed | Certificate Reference |
|---|---|---|---|
| CCS | China Classification Society | EH36 / DH36 / EH32 / AH36 | CCS 材料与焊接规范 |
| DNV | DNV (Det Norske Veritas) | EH36 / DH36 / AH36 | DNV Rules for Classification of Ships |
| ABS | American Bureau of Shipping | EH36 / DH36 / AH36 | ABS Rules Part 2 Materials |
| LR | Lloyd’s Register | EH36 / DH36 / AH36 | LR Rules for Ships |
| BV | Bureau Veritas | EH36 / DH36 / AH36 | BV Rules NR216 |
| NK | ClassNK (Nippon Kaiji Kyokai) | EH36 / DH36 / AH36 | NK Rules Part K |
| KR | Korean Register | EH36 / DH36 / AH36 | KR Guidance for Steel Plates |
| RINA | Registro Italiano Navale | EH36 / DH36 / AH36 | RINA Rules Pt.2 Ch.4 |
| RS | Russian Maritime Register of Shipping | EH36 / DH36 / AH36 | RS Rules Part XIII |
International Equivalent Grades
| Standard / Source | Equivalent Grade | Impact Test Temperature | Minimum Yield |
|---|---|---|---|
| GB/T 712-2011 (China) | EH36 / DH36 (EH36-Z35, DH36-Z35) | -40°C / -20°C | 355 MPa |
| ASTM A131/A131M (USA) | Grade EH36 / Grade DH36 | -40°C / -20°C | 355 MPa |
| IACS UR W11 / class rules | EH36 / DH36 | -40°C / -20°C | 355 MPa |
| TMCP variant | EH36-TM / DH36-TM | -40°C / -20°C | 355 MPa |
| EN 10025-2 (structural reference) | S355J2 / S355K2 | Not a marine grade | 355 MPa |
Chemical Composition (Ladle Analysis, % max)
| Grade | C | Si | Mn | P | S | Al (soluble) | Cu | Ni | Cr | Mo | N | CEV |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| EH36 (≤ 50 mm) | ≤ 0.18 | ≤ 0.50 | 0.90 – 1.60 | ≤ 0.035 | ≤ 0.035 | ≥ 0.015 | ≤ 0.35 | ≤ 0.40 | ≤ 0.20 | ≤ 0.08 | ≤ 0.0090 | ≤ 0.36 |
| DH36 (≤ 50 mm) | ≤ 0.18 | ≤ 0.50 | 0.90 – 1.60 | ≤ 0.035 | ≤ 0.035 | ≥ 0.015 | ≤ 0.35 | ≤ 0.40 | ≤ 0.20 | ≤ 0.08 | ≤ 0.0090 | ≤ 0.36 |
| EH36 / DH36 (50 – 100 mm) | ≤ 0.18 | ≤ 0.50 | 0.90 – 1.60 | ≤ 0.030 | ≤ 0.030 | ≥ 0.015 | ≤ 0.35 | ≤ 0.40 | ≤ 0.20 | ≤ 0.08 | ≤ 0.0090 | ≤ 0.38 |
CEV formula: C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15. TMCP-delivered material is supplied with Pcm ≤ 0.21. Ni + Cu + Cr additions are agreed with the class society when the steel is intended for low-temperature service or heavy gauge.
Mechanical Properties
| Grade | Thickness | Yield ReH | Tensile Rm | Elongation A | Charpy V Longitudinal | Charpy V Transverse |
|---|---|---|---|---|---|---|
| EH36 | 6 – 50 mm | ≥ 355 MPa | 490 – 620 MPa | ≥ 21 % | ≥ 34 J at -40°C | ≥ 24 J at -40°C |
| EH36 | > 50 – 100 mm | ≥ 355 MPa | 490 – 620 MPa | ≥ 21 % | ≥ 34 J at -40°C | ≥ 24 J at -40°C |
| DH36 | 6 – 50 mm | ≥ 355 MPa | 490 – 620 MPa | ≥ 21 % | ≥ 34 J at -20°C | ≥ 24 J at -20°C |
| DH36 | > 50 – 100 mm | ≥ 355 MPa | 490 – 620 MPa | ≥ 21 % | ≥ 34 J at -20°C | ≥ 24 J at -20°C |
Charpy specimens are taken in the rolling direction (longitudinal) and transverse to the rolling direction, 10 × 10 mm where thickness permits; sub-size specimens are used below 12 mm with the acceptance values defined by the applicable class rule. Yield ratio, strain-ageing and through-thickness (Z35) tests are available as supplementary requirements.
Processing & Fabrication Guidance
- Thermal cutting: CNC flame cutting (multi-torch, up to 150 mm) or high-definition plasma. Contour accuracy ±1 mm, edge squareness controlled by cutting speed and kerf compensation.
- Preheating: 50°C – 100°C for thickness above 30 mm or when CEV is at the upper limit; measure 75 mm from the cut/ weld edge.
- Welding: SAW, FCAW, GMAW and SMAW with hydrogen-controlled consumables (H5 / H10 grade). Suggested heat input 10 – 35 kJ/cm, interpass temperature ≤ 250°C, no preheat above 100°C unless the class rule requires otherwise.
- Post-weld heat treatment: not normally required. Where specified, stress relief at 580°C – 620°C with controlled heating and cooling rates.
- Forming: cold forming permitted to a minimum inside radius of 3t (t ≤ 20 mm); hot forming above 900°C followed by normalizing when the class society requires it.
- Surface preparation: shot blasting to Sa2.5 with 40 – 75 µm profile, then zinc-silicate shop primer 15 – 25 µm DFT.
- Traceability: heat number, society stamp and plate identification retained to the end of fabrication.
Typical Applications
- Hull shell plating, deck and bottom plating of bulk carriers, tankers, container ships and offshore support vessels
- Hatch covers, coamings, bulkheads and superstructure blocks
- Offshore platform structures, crane pedestals and heavy deck panels
- Ship repair, jumboisation and block replacement projects
Request EH36 / DH36 High-Strength Marine Steel Plate Quotation & Mill Certificate
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