The production process of cold-rolled seamless steel pipe is generally more complicated than that of hot-rolled: tube is first to three roller skew rolling, then, to carry out a sizing test after extrusion. Round tube needs to cut through cutting machine and the length is about 1 meter. Entering the annealing process, annealing carry out pickling should pay attention to whether the surface has a large number of foaming, if there is a large number of bubbles produced that the quality of the steel pipe is not up to the corresponding standard. Cold-rolled seamless steel pipe is shorter than the hot rolled seamless steel pipe in appearance, but the surface looks brighter than the thick walled seamless steel tube.
Advantage of cold-rolled seamless steel pipe:
Forming fast, high yield, and no damage to the coating, it can be made into a variety of cross sectional form to meet the needs of the use of conditions; Cold rolling can cause great plastic deformation, so as to improve the yield of the steel.
The technological process of cold-rolled seamless steel pipe:
Round billet→heating→perforation→annealing→pickling→annoit→cold rolling→heating→straightening→hydrostatic test→signing→storage