Introduction
Shipbuilding steel is a kind of special steel used for shipbuilding. It is also called marine steel plate or offshore platform steel plate. With the rapid development of modern shipbuilding industry, the demand for shipplate is increasing. It has certain requirements for the strength and toughness of shipbuilding steel. The shipbuilding steel grades mainly include A, B, D, E, AH32/36/40, DH32/36/40, EH32/36/40 and so on.
Characteristics of Shipbuilding Steel
1.Good weldability and forming performance: The shipbuilding steel needs to have good weldability and forming performance so as to realize the partial or total welding of the ship.
2.High corrosion resistance: The corrosion in seawater of shipbuilding steel will cause structural damage and make the ship lose its stability. The shipbuilding steel needs to have high corrosion resistance and has good antirust performance.
3.High impact toughness and low temperature toughness: The impact toughness and low temperature toughness are two important indicators in the performance evaluation of shipbuilding steel. The marine environment is difficult and the working temperature is low. The impact toughness and low temperature toughness of shipbuilding steel will directly affect the safe operation of ships.
4.High strength: The main force supporting the ship must have certain strength, otherwise the stability of the ship will be affected. Shipbuilding steel must have certain strength and toughness, so as to be able to withstand the great impact of waves and wind on open oceans.
Details of Smelting Shipbuilding Steel
1.Heat treatment: After casting and cooling, the hull and other components should be given appropriate heat treatment (normalizing and tempering and quenching, etc.), so as to obtain the required mechanical properties.
2.Surface engineering: Shipbuilding steel should undergo a particular surface treatment. The surface can be treated with rust-preventives, corrosion inhibitors and paint.
3.Post-welding treatment: Shipbuilding steel should be subjected to post-welding treatment, such as semi-static quenching, low temperature annealing, welding stress relief, welding post-welding heat treatment, etc., to achieve the weldability and strength requirements.
Conclusion
Shipbuilding steel is an important material for shipbuilding. It has the characteristics of good weldability and forming performance, high corrosion resistance, high impact toughness, low temperature toughness and high strength. The heat treatment, surface engineering and post-welding treatment should all meet the requirements in the process of smelting shipbuilding steel.