The piston rod is processed by rolling, because the residual surface stress is left on the surface, which is conducive to the sealing of small cracks on the surface and prevents the expansion of sedimentation. In order to improve the corrosion resistance of the surface, the piston rod can slow down the formation or expansion of fatigue cracks, thus increasing the fatigue limit of the cylinder rod. According to rolling forming, the rolling surface forms a layer of cold work hardening layer, which reduces the ductility and plastic deformation of the contact surface of the cutting pair, thereby improving the wear resistance of the surface of the hydraulic cylinder rod and preventing damage caused by cutting. scald. After rolling, the reduction in roughness values improves the interfit properties. At the same time, it reduces the friction damage to the seal ring or hydraulic seal when the piston of the hydraulic cylinder rod moves, and improves the overall service life of the hydraulic cylinder.
The rolling process is a high-efficiency and high-quality process strategy. Now take the 165mm-diameter Mirror Doctor brand cutting and rolling head (46 steel seamless pipe) as an example to prove the material rolling effect. After rolling, the roughness of the hydraulic cylinder rod is reduced from Ra3.4-6.3um before rolling to Ra0.3-0.7um, the surface strength of the hydraulic cylinder rod is increased by about 40%, and the fatigue limit of the surface layer of the hydraulic cylinder rod is increased by 20%. The service life of the hydraulic cylinder is increased by 2 to 3 times, and the efficiency of the rolling process is about 16 times higher than that of the cutting process. The left and right statistical data show that the rolling process is highly efficient and can greatly improve the process performance of hydraulic cylinder rods.
