Cold drawn steel pipe is a kind of steel pipe, that is, it is classified according to different production processes, which is different from hot rolled (expanded) pipe. In the process of expanding the diameter of the capillary tube or the raw material tube, it is made by multiple cold drawing processes, usually on a single-chain or double-chain cold drawing machine of 0.5 to 100T. Cold rolled (dial) steel pipes are divided into general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, machined pipes, thick-walled pipes, small diameter and internal mold cold drawn pipes and other steel pipes , Also includes carbon thin-walled steel pipes, alloy thin-walled steel pipes, stainless steel thin-walled steel pipes, special-shaped steel pipes. The outer diameter of cold drawn steel pipe can be up to 6mm, the wall thickness can be up to 0.25mm, the outer diameter of thin-walled pipe can be up to 5mm and the wall thickness is less than 0.25mm. The accuracy and surface quality are significantly better than hot rolled (expanded) pipe Restrictions, its caliber and length are subject to certain restrictions.