Welded steel pipe refers to a steel pipe with seams on the surface that is welded after bending and deforming a steel strip or steel plate into a circular, square or other shape. The blanks used for welded steel pipes are steel plates or strips. With the rapid development of continuous rolling production of high-quality strip steel and the advancement of welding and inspection technology, the quality of welds has been continuously improved, and the varieties and specifications of welded steel pipes have increased day by day, and seamless steel pipes have been replaced in more and more fields.

The steel sheet pile is a kind of steel structure with linkages on the edge, and the linkages can be freely combined to form a continuous and compact retaining wall or water retaining wall.

Anti-corrosion steel pipe refers to steel pipes that have been processed by anti-corrosion technology, which can effectively prevent or slow down the corrosion phenomenon caused by chemical or electrochemical reactions during transportation and use.

Decarburization is a phenomenon in which the surface carbon content of steel pipes (such as CS seamless pipes and welded steel pipes) decreases during heat treatment. The essence of decarburization is that the carbon atoms in the steel pipe react with the furnace atmosphere such as hydrogen or oxygen at high temperature to form methane or carbon monoxide.

During thermal processing (welding), due to the uneven heating temperature, compression plastic deformation occurs in the high temperature area. During cooling, the contraction of this part is prevented by other parts (low temperature region or first cooling part), resulting in residual stress and various deformations. However, the hot-processed steel pipes (welded pipes or thermally expanded seamless pipes) in the steel market mainly show bending deformation.

The seamless steel pipe is expressed as outer diameter, wall thickness, and thick-walled seamless steel pipe is mainly used for machining, coal mining, hydraulic steel and other purposes. How to solve the rust spots of thick-walled seamless steel pipes? There are two ways to solve it.