The difference between LR DH32 and LR DH36 steel plate

LR DH32 is a higher-strength structural steel plate certified by Lloyd's Register (LR) for shipbuilding and marine applications . The "D" grade signifies it is impact tested at -20°C, ensuring reliable toughness for vessels operating in cold marine environments . It has a minimum yield strength of 315 MPa (46 ksi) and tensile strength ranging from 440 to 590 MPa (64-85 ksi), with a minimum elongation of 22% . The chemical composition is strictly controlled with carbon ≤0.18% and manganese 0.90-1.60% . This grade is typically supplied in normalized or controlled rolled conditions and is widely used for hull structures, offshore platforms, and general shipbuilding components .

LR DH36 is also a higher-strength structural steel plate certified by LR, with the same impact test temperature of -20°C . The "36" denotes a minimum yield strength of 355 MPa and tensile strength ranging from 490 to 620 MPa, with a minimum elongation of 21% . The chemical composition is similar to DH32 with carbon ≤0.18% and manganese 0.90-1.60%, though DH36 may contain microalloying elements like Nb and V to achieve its higher strength . This grade is designed for more demanding load-bearing applications in shipbuilding, including hull shells, longitudinal stiffeners, and primary structures .

Both LR DH32 and LR DH36 are LR-certified higher-strength marine steels with impact toughness tested at -20°C, ensuring reliable performance in cold marine environments . Their primary difference lies in strength level: DH32 offers a minimum yield strength of 315 MPa with tensile strength of 440-590 MPa, suitable for general high-strength hull construction and secondary structures, while DH36 provides a higher minimum yield strength of 355 MPa with tensile strength reaching 490-620 MPa, designed for more demanding load-bearing applications requiring superior strength . Both grades feature controlled chemical composition and maintain good weldability for critical marine service, making them essential materials for shipbuilding and offshore platforms .

Chemical Composition

Mechanical Property