Seamless steel pipes have hollow sections and are widely used as pipelines for transporting fluids, such as pipelines for transporting oil, natural gas, gas, water and some solid materials. Compared with solid steel such as round steel, steel pipe is lighter in weight when its bending and torsional strength is the same, and it is a kind of economic section steel.
Seamless steel pipe refers to the pipe production, which is made of steel ingots or solid pipe blanks through perforation, and then made of hot-rolled, cold-rolled or cold drawn. The inner wall of the pipe has no meaning of combining cracks; The welded steel pipe refers to the steel pipe with joints on the surface, which is welded after the steel belt or steel plate is bent and deformed into circular, square and other shapes, and the joints of secondary welding on the inner wall of the pipe.
In short, seamless steel pipe is relative to welded steel pipe, because welded steel pipe is butt welded with steel strip, and seamless steel pipe is made of a whole round steel hollow without weld.