The hydraulic cylinder pipes is rolled, and the residual pressure on the surface layer is left to help the surface of the surface crack, which hinders the expansion of the erosion. Thereby, the surface corrosion resistance is improved, and the generation or expansion of the fatigue crack can be delayed, thereby improving the fatigue strength of the cylinder tube. By rolling forming, the rolling surface forms a cold hardening layer, which reduces the elastic and plastic deformation of the grinding contact surface, thereby improving the wear resistance of the inner wall of the cylinder tube and avoiding burns caused by grinding. After rolling, the surface roughness value is reduced to improve the compounding property.
Rolling processing is a kind of chipless processing, which utilizes plastic deformation of metal at normal temperature to flatten the microscopic unevenness of the surface of the workpiece to achieve the purpose of changing the surface structure, mechanical properties, shape and size. Therefore, this method can achieve both the finishing and strengthening purposes at the same time, which is impossible for grinding.
No matter what kind of processing method is used, there will always be fine unevenness on the surface of the part, and there will be staggered peaks and valleys.
Rolling processing principle: It is a kind of pressure finishing process, which utilizes the cold plasticity characteristics of metal in normal temperature state. The rolling tool is used to apply a certain pressure to the surface of the workpiece to make plastic flow of the surface metal of the workpiece and fill in the original residue. In the low concave wave valley, the surface roughness of the workpiece is reduced. Due to the plastic deformation of the rolled surface metal, the surface layer is cold hardened and the grain is thinned to form a dense fibrous shape, and a residual stress layer is formed, and the hardness and strength are improved, thereby improving the wear resistance and corrosion resistance of the surface of the workpiece. Sex and fit. Rolling is a non-cutting plastic working method.