For this reason, I specifically asked professionals from Shanghai Yuma Industrial Co., Ltd., which specializes in ship plate trading: CCSA and CCSB are both types of ship plates, that is, structural steel for general-strength ship hulls. The so-called general-strength steel for hull structures means that according to the China Classification Society quality standards, the quality of the plates is divided into four grades: A, B, C, and D. The A and B-grade steel plates are all general-strength plates, and the Mn content differs in chemical composition. It is very big, and there is no other difference in mechanical properties. The yield and tensile strength are the same. The difference is the experimental temperature of impact work, which is 20 degrees for grade A and 0 degrees for grade B.