Machining of hand valve stem

The material of the hand-held valve stem is made of hard aluminum alloy which is easy to cut. Because the valve rod surface is sliding in the sealing ring directly during reversing, the surface needs high hardness and low roughness value. Therefore, the valve stem with high dimension precision and low surface roughness value is obtained by using close CNC machine tool and gemstone cutter. After turning, in order to improve the surface quality and hardness of the friction sealing surface of the valve stem, rolling process of the valve stem surface is carried out. Rolling is a rolling process for rolling hard and smooth rollers and metal surfaces of the stem, and a slight plastic deformation on the surface of the stem. Principle of rolling is shown below.

The surface roughness of the rolled valve stem can reach 0.1-0.8um mirror surface, and the wear resistance and fatigue strength of the rolled valve stem are improved due to the hardening of the rolled surface. The features of the above rolling process are beyond the cutting process. The rolling machine with cash can roll not only the cylindrical surface of the valve stem, but also the fillet transition part of the valve stem. After all the processing, hard anodizing surface treatment was carried out to further improve the surface hardness and corrosion resistance of the valve stem and meet the performance and requirements of the valve stem.