The CK45 chrome plated bar is a connecting part that supports the work of the piston. Most of them are used in the cylinder and cylinder movement executing parts. It is a moving part with frequent movement and high technical requirements. Taking a hydraulic cylinder as an example, it consists of: a cylinder, a 45# piston rod (cylinder rod), a piston, and an end cover. The quality of its processing directly affects the life and reliability of the entire product. 45# piston rod has high processing requirements, and its surface roughness requirement is Ra0.4～0.8um. It has strict requirements on coaxiality and wear resistance. The basic feature of the cylinder rod is the slender shaft machining, which is difficult to process and has always plagued the processing personnel.
The CK45 piston rod is rolled to improve the surface corrosion resistance and delay the generation or expansion of fatigue cracks, thus improving the fatigue strength of the cylinder rod. 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 cylinder rod surface and avoiding burns caused by grinding. After rolling, the surface roughness value is reduced to improve the compounding property. At the same time, the friction damage to the sealing ring or the sealing member during the movement of the cylinder rod piston is reduced, and the overall service life of the oil cylinder is improved. The rolling process is a high quality process.