Ship hull structural steel plate is referred to as ship plate. Due to the harsh working environment of the ship, the ship shell to be subjected to seawater chemical corrosion, galvanic corrosion and sea life, microbial corrosion; hull to withstand greater wind and wave impacts and alternating loads; the shape of the ship so that the processing method is complex and so on, so the hull of the structural steel requirements are stringent.
First of all, good toughness is the most critical requirements, in addition, the requirements of high strength, good corrosion resistance, welding performance, processing and molding performance and surface quality. In order to ensure the quality and ensure that there is enough toughness, the requirements of the chemical composition of the Mn / C in 2.5 or more, the carbon equivalent also has strict requirements, and by the ship inspection department recognized by the production of steel mills.
Structural steel for hulls is divided into two types: general thickness and high strength steel. General strength steel is divided into four grades A, B, C and D according to quality; high strength steel is further divided into two strength levels and three quality grades; AH32, DH32, EH32, AH36, DH36, EH36.
