Uses: Used in electro-hydraulic switch machine railway switch conversion system products, hydraulic drive mechanism hydraulic cylinder piston rod, hydraulic cylinder key components, similar to the general hydraulic cylinder piston rod; Features: It is a kind of high-precision shaft parts used for axial movement. Most of the rod parts need to be ground. Generally, both ends are equipped with threaded (external or internal thread) interfaces, and the oil seal groove with O-ring in the middle requires high surface roughness and straightness. Process requirements: blanks are generally made of steel bars or forgings. The main processes include: heat treatment-turning-grinding-electroplating-post-plating fine grinding and other processes; the main processing equipment includes CNC lathes, CNC cylindrical grinders, quenching equipment, and electroplating equipment. Key inspection items: surface roughness, coating thickness, appearance scratches, straightness, cylindricity and other items;