How To Choose The Trim Material Of The Pneumatic Piston Shut-off Valve

1. Wear resistance

The wear of the valve seat and valve core material will cause the valve to leak and change the flow characteristics. If the wear is severe, a new small flow path will be formed. Even the thin walls of the valve trim are penetrated.

The basic form of wear may be the grinding of solid particles, the scouring of high-speed media, and the cavitation caused by cavitation. In order to improve wear resistance, the surface hardness must be increased. In the case of flash evaporation and cavitation, effective methods should be taken: when the trim of the pneumatic piston shut-off valve is small, solid carbide can be used; special methods can also be used to surfacing on the parent material to form a spray Welded carbide.

2. Corrosion resistance

The corrosive properties of the medium are an important factor in how to select materials. For strong corrosive media, the choice of corrosion-resistant materials must be selected according to specific conditions such as the type, concentration, temperature, and pressure of the medium.

3. Temperature resistance

For materials working at high temperature, tensile strength, yield limit, creep (above 450), hot hardness, impact strength and aging should be considered; at the same time, corrosion resistance, heat treatment temperature and plastic deformation should also be considered. The increase in temperature will also cause the movable parts to become smaller, stuck and bonded. Cyclic changes in temperature will have adverse effects on the gasket, packing and guide sleeve of the pneumatic piston shut-off valve.