What is the difference between marine steel plate and common steel plate?

Steel plate for hull structure is abbreviated as ship plate. Due to the bad working environment of the ship, the shell of the ship is subject to the chemical corrosion and electrochemical corrosion of the sea water and the corrosion of marine organisms and microorganisms; the ship hull is subject to large wind and wave impact and alternating load; the ship shape makes its processing method complex and other reasons, so the steel requirements for the ship hull structure are strict.

First of all, good toughness is the most critical requirement. In addition, it requires high strength, good corrosion resistance, welding performance, processing and molding performance and surface quality. In order to ensure the quality and enough toughness, the chemical composition of Mn / C is required to be more than 2.5, and the carbon equivalent is also strictly required, which is produced by the steel plant approved by the ship inspection department.

There are two kinds of structural steel for hull: general thickness steel and high-strength steel. General strength steel is divided into four grades according to its quality: A, B, C and D. high strength steel is divided into two strength grades and three quality grades: AH32, DH32, EH32, AH36, DH36 and EH36.