Introduction to the cold drawing method of common steel pipes: production of high-precision cold-drawn pipes - hydraulic cylinders compared with traditional cutting processes, with the following characteristics: high production efficiency: using a conventional method to produce a cylinder with an inner diameter of 420 mm and a length of 12 meters The tube takes 154 hours and is produced in a cold drawing process in just 4 minutes.
High authentic rate: Because the rolling head of the boring head also plays a guiding role, during the cutting process, the blank tube is deflected due to its own weight, causing the rolling head and the boring tool to be biased, resulting in waste. The authentic rate can only reach about 60%, and the cold drawing method can produce more than 95%. High metal utilization rate: the cylinder is manufactured by the traditional boring method, and the metal utilization rate is only 50-70%.
When produced by the cold drawing method, the metal is not only cut into iron, but can be extended by 30%, and the metal utilization rate can reach 95%. It can improve the mechanical properties of the finished pipe metal: it can be produced by the drawing method, so that the blank can be plastically deformed by more than 30%, and the strength limit of the finished pipe metal is greatly improved due to work hardening.
Generally, the strength limit of the inner layer of the finished pipe is increased by 60%. The high-precision cold-drawn tube is made of seamless hot-rolled steel pipe
and straight-slot welded pipe
as a blank. After chemical treatment, it is drawn on a special cold drawing machine through a special deformation principle to produce a high-precision pipe. Its dimensional accuracy is H10～H8, the straightness is 0.35～0.5mm/m, and the surface roughness is Ra1.6-0.4.