How to identify seamless steel pipes and welded pipes

Identification method: Look at the inside of the pipe, because the outside will be processed. Some welded pipes have a gap inside, which can be seen, and some are processed, which is not easy to see. You can touch it slowly with your hands, or look at the specifications. Welded pipes are relatively thin. Seamless steel pipe manufacturers, welded pipes are made directly by machines with stainless steel strips (rolled up), and seamless pipes are pierced with round steel or pipe blanks.

Principle of seamless steel pipe production
The production method can be divided into hot-rolled pipe, cold-rolled pipe, cold-drawn pipe, extruded pipe, etc. according to the production method. Hot-rolled seamless pipe is generally produced on an automatic pipe rolling unit. The solid pipe billet is inspected and the surface defects are removed, cut into the required length, centered on the end face of the perforated end of the pipe billet, and then sent to the heating furnace for heating and perforated on the perforator. While perforating, it rotates and moves forward continuously. Under the action of the roller and the head, a cavity is gradually formed inside the pipe billet, which is called a rough pipe. Then it is sent to the automatic pipe rolling machine for further rolling. The wall thickness is adjusted by the leveling machine, and the diameter is determined by the sizing machine to meet the specification requirements.