What is shipbuilding steel plate production technology

Grade A and B shipbuilding steel plates of general strength can meet the requirements of their process and mechanical properties through ordinary rolling, so the production process is relatively simple; while the production of Grade D, E and high-strength shipbuilding steel plates requires relatively complete equipment. Under the equipment, it is realized by means of controlled rolling and controlled cooling process or heat treatment process. At the same time, the internal steel purity of the supplied billet is relatively high, especially the content of S, P, N, O, H, etc. in the steel must be strictly controlled.

In order to reduce costs, it is the best strategy to produce shipbuilding steel plates by hot rolling or controlled rolling instead of normalizing. High-strength shipbuilding steel plates with a thickness of less than 35mm have been produced by two-stage controlled rolling; high-strength ship plates with a thickness of more than 35mm are mostly produced by hot rolling and normalizing.

In order to ensure the performance of high-strength shipbuilding steel plates, micro-alloying technology is used. By adding alloying elements such as Nb, V, and Ti to the steel, combined with the controlled rolling process, the grains are refined and the strength and toughness are improved.

Grade D, E series shipbuilding steel plates are required to have good low temperature toughness and good welding performance, which should be guaranteed first in terms of steel smelting process, and secondly, an effective controlled rolling and controlled cooling process should be implemented. In recent years, major domestic iron and steel enterprises have fully realized the importance of improving the internal quality of steel, and relying on the progress of smelting technology, improvements have been made in hot metal desulfurization and slag skimming, steelmaking hydrogen blowing, and vacuum refining outside the furnace, which has significantly reduced the harmful effects of steel.