Classification of shipbuilding plates

Classification of shipbuilding plates

Shipbuilding steel plate refers to the carbon steel and alloy steel plate used in offshore and Marine engineering, and its classification is mainly based on its strength grade, toughness grade, and the relevant classification society certification standards. Common grades are A, B, D, E, AH32/36/40, DH32/36/40, EH32/36/40.

1. Divide by intensity level
Marine steel plates can be divided into the following three categories according to yield strength:
(1) Normal Strength Steel Plates
Yield strength: not less than 235 MPa.
Common brands: A, B, D, E.
A: Suitable for zero environment, general minimum requirements;
B: Slightly higher than grade A, slightly more widely used;
D/E: Used in low temperature environment, higher toughness requirements.
(2) High Strength Steel Plates
Yield strength: 315 MPa, 355 MPa, 390 MPa, 460 MPa, etc.
Common brand: AH32, AH36, DH36, EH36, FH36, etc.
A/D/E/F: indicates the toughness level of the steel plate (grade F has the highest toughness).
Number: Indicates the yield strength (for example, AH36 indicates a yield strength of 36 ksi, that is, about 355 MPa).
(3) Ultra High Strength Steel Plates
Yield strength: higher than 460 MPa.
Common brand: EH40, FH40, EH47, FH47, etc.

2. According to the toughness level
According to the ambient temperature, Marine steel plates are divided into different toughness levels:
Grade A steel plate: suitable for normal temperature environment, minimum toughness requirements.
Grade B steel plate: toughness is slightly higher than grade A, can be used for slightly low temperature environment.
Grade D steel plate: suitable for use at -20°C.
Grade E steel plate: suitable for use at -40°C, with good low temperature toughness.
Grade F steel: The highest toughness, suitable for use in lower temperatures and more harsh environments, such as polar environments.

3. Classification by classification society certification
Marine steel plates need to meet different international classification society standards, usually certified by the following authorities:
American Bureau of Shipping (ABS) : such as ABS A and ABS AH36.
DNV (Det Norske Veritas) : such as DNV AH36 and DNV EH40.
LR (Lloyd's Register) : for example, LR DH36, LR EH32.
Bureau Veritas (BV) : such as BV AH36 and BV DH40.
China Classification Society (CCS) : such as CCS A and CCS EH36.
GL, NK, KR and other classification society certification.