Cold drawn steel tube if you would like to get a smaller size and better quality seamless tube, must adopt the method of cold rolling, cold drawing or both combined. Cold rolling is usually conducted on two-high rolling mill, steel pipe in variable cross section round hole groove and conical head of the ring
Rolling in the groove. Cold drawing usually in 0.5 ~ 100 t cold drawn tubes single or double chain chain cold drawing machine.

Cold drawn steel tube with drawing, extrusion, produced by the method of perforation of the whole root no seamless steel pipe steel pipe surface. Is a hollow section, no seams around, round, square, rectangular steel. Is made from solid tube ingot or the perforation capillary,
Then through cold dial.

Cold drawn steel tube is used in the mechanical structure, the size of the hydraulic equipment of high precision and good surface finish of precision cold drawn seamless tube. Choose precision seamless tube manufacturing mechanical structure or hydraulic equipment, etc., can greatly save the machining time, improve the material utilization

And at the same time to improve the quality of the product.

High quality carbon structural steel seamless tube, cold mainly with 10, 20, steel manufacturing, in addition to guarantee the chemical composition and mechanical properties to do water pressure beam impact tubes test, edge, flaring, flattening test, etc.

Cold drawing processing steel tube is work hardening. The cold drawing metal plastic deformation occurs, the crystals have multiple slip system startup, internal dislocation motion intercept each other, many dislocation were pinning and dislocation caused by product and dislocation source to stop the action at the same time.
The above
A series of process results in the decrease of the dislocation mobility, crystals in dislocation density increased significantly. When plastic deformation occurs, further stress increase and enough to make side impact beams pinning dislocation movement, screw dislocation glide, edge dislocation cannot pay slip, so that the hair
Dislocation cross section, increase the fixed order.

So by cold drawing processing metal internal dislocation density increases, the dislocation mobility is reduced, is difficult to produce dislocation and difficult to mobile dislocation, and hardness, strength, improve the metal materials. This is the metallography principle of cold drawing process.