The commonly used welding steel pipes are divided into the following three types of welding processes used during production.
① Continuous furnace welding (forging welding) steel pipe: It is characterized by high production efficiency and low production cost, but the welding joint metallurgy is incomplete, the weld quality is poor, and the comprehensive mechanical performance is poor.
② Resistance welding steel pipe: It is characterized by high production efficiency, high degree of automation, and no need to welding and welding during welding. The damage to the mother material is small, and the deformation and residual stress after welding are also small. However, its production equipment is more complicated, the equipment investment is high, and the surface quality requirements of the welding joint are relatively high.
③ Arc welded steel pipe: It is characterized by the welding joint to achieve a complete metallurgical binding, and the mechanical performance of the joint can fully achieve or approach the mechanical properties of the mother material. Depending on the shape of the weld, the arc welded steel pipe can be divided into two types: straight slit pipe and spiral welded governance. According to the protection methods taken during welding, the arc welded steel pipe can be divided into buried arc welded steel pipes and melting polar gas protection. There are two types of welding steel pipes.
