Production process of cold drawn tube

- Jun 03, 2020-

Cold drawn pipe is a kind of steel pipe when it is used. It is classified according to different production processes when it is operated, which is mainly different from hot rolled (expanded) pipe. 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 cold-drawn pipe processing steel tube is work hardened. The metal deforms plastically during cold drawing, and multiple slip systems start inside the crystal. The dislocation movements intercept each other. Many dislocations are pinned, causing dislocations to accumulate and at the same time the dislocation source stops. The above-mentioned series of processes lead to a decrease in the dislocation mobility, and the density of dislocations in the crystal increases significantly. When the plastic deformation further occurs, the stress increases enough to start the movement of the pinned dislocations, the screw dislocations intersect and slip, and the blade dislocations cannot intersect and slip, so that the dislocations intersect and the fixed order increases. Therefore, through the cold drawing process, the internal dislocation density of the metal is increased, and the dislocation mobility is reduced. It is difficult to generate dislocations and it is difficult to move the dislocations, so the hardness and strength of the metal material are improved. This is the metallurgical principle of cold drawing. A