What are the differences between seamless steel pipe and welded pipe

On the appearance of steel pipe, the difference between seamless steel pipe and welded pipe is that there are welding seams on the inner wall of welded pipe, while seamless steel pipe does not have it.

The pressure of seamless steel pipe is higher, the welded pipe is generally about 10 MPa, and now the welded pipe can be seamless by special treatment. Seamless steel pipe is formed in one time during rolling. Welded pipe needs to be welded after rolling, generally including spiral welding and straight welding. The performance of seamless steel pipe is better, of course, the price is higher. Seamless steel tube is made of steel ingot or solid tube blank by piercing and then by hot rolling, cold rolling or cold drawing. Seamless steel pipe has hollow section, which is widely used to transport fluid. Welded pipe refers to the steel pipe with a joint on the surface, which is formed by bending steel strip or steel plate into a circle and then welding. The blank used for welded pipe is steel plate or strip steel.

Identification method: look inside the pipe, because the outside will be treated. There is a gap in the welded pipe, some of which can be seen, and some of which can not be easily seen. You can touch it slowly by hand, or look at the specification. The welded pipe is relatively thin in wall thickness, and the wall thickness of the seamless steel pipe is relatively thicker.