Plastic flow and residual compressive stress of hydraulic cylinder pipes

- Jun 20, 2019-

In the process of operating the hydraulic cylinder pipes, the rolling process is mainly used, and the surface residual stress is left on the surface layer during the production, which contributes to the sealing of the surface micro crack and hinders the expansion of the erosion effect. 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.


Cylinder tube 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.


The cylinder tube is a kind of pressure finishing process. It utilizes the cold plasticity characteristic of the metal at normal temperature. 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 the original concave depression. In the trough, 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.