The general strength hull structure steel is divided into 4 grades: A, B, D, E. The yield strength (not less than 235MPa) of these 4 grades of steel is the same as the tensile strength (400～520N/mm^2). It's just that the impact energy is different at different temperatures. The test temperature for CCS D (CCS Grade D)hull structure steel is -20℃.
Review of CCS D hull structure steel quality certificate:CCSD steel mills must deliver the goods in accordance with the specifications stipulated in the contract according to the requirements of the user and provide the original quality certificate. The certificate has the following contents:
(1) Specification requirements;
(2) Quality record number and certificate number;
(3) Furnace batch number and technical grade;
(4) Chemical composition and mechanical properties;
(5) Classification society approval certificate and surveyor's signature.
For the delivery of marine steel, the physical object should have the manufacturer's logo, etc. Specifically:
(1) Classification society approved mark;
(2) Use paint to frame or paste the mark, including technical parameters such as: furnace batch number, standard grade, length and width dimensions, etc.;
(3) The appearance is smooth and smooth without defects.
The main classification societies are:
CCS
ABS
GL
BV
DNV
NK
LR
KR
RINA
