||Marine steel refers to the steel used to manufacture the hull structure of ships and inland rivers. It is usually high quality carbon steel and low alloy steel. Marine steel requires certain strength, toughness, low temperature and corrosion resistance, and good welding performance.
Because of the harsh working environment of ships, the hull and hull are subject to chemical corrosion, electrochemical corrosion and corrosion of marine organisms and microorganisms; the hull is subjected to large wind and wave impact and alternating load; the shape of ships makes its processing method complex and other factors, so the requirements for steel for hull structure are strict. Firstly, good toughness is the most critical requirement. In addition, it requires high strength, good corrosion resistance, welding performance, processing and forming performance and surface quality. In order to ensure quality and toughness, it is required that the chemical composition of Mn/C is above 2.5, and carbon equivalent is also strictly required, which is produced by steel mills approved by the ship inspection department. According to the minimum yield point, hull structural steels are divided into general strength structural steels and high strength structural steels. Structural steels for hull are classified into general strength and high strength steels, which are classified into four grades: A, B, D and E by quality; high strength steels are classified into two strength grades and three quality grades; AH32, DH32, EH32, AH36, DH36 and EH36.
The general strength structural steels in China Classification Society Standard are classified into four quality grades: A, B, C and D (CCSA, CCSB, CCSC and CCSD); and the high strength structural steels in China Classification Society Standard are classified into three strength grades and four quality grades.Hot Rolled Steel price