Pneumatic valve on the choice need to consider what factors

Pneumatic valve is a valve with pneumatic actuator, pneumatic actuator execution speed is relatively fast, fast switching speed. Seconds/time, so usually also called pneumatic quick cut-off valve. The pneumatic valve on the choice need to consider what factors? In order to avoid pneumatic trims ( Valve core and valve seat) Wear, erosion and cavitation, on the surface of the high temperature circumstances to consider material hot hardness, prevent metal hardness change. Under the high pressure difference, the fluid has focused on the trims for most of the energy release, the valve internals have super load, and high temperatures, most of the material mechanical properties, material softening, greatly influence the service life of the trims. And the same medium, under the condition of high temperature, its molecular activity is relatively active, some with general corrosive medium may have on the body and trim brings the serious corrosion damage, metal ion state of medium to high speed into the metal inside, cause changes in the characteristics of the materials, such as thermal expansion, intergranular corrosion, etc. , therefore, the choice of materials, in addition to price, also should consider more factors produced by the failure. Therefore, we should correct selection of appropriate materials, prolong the service life of pneumatic valve. Also consider the high temperature aging influence on material physical properties, such as between the toughness and the change of corrosion. When using temperature at or above the heat treatment temperature, trims will produce annealing, problems such as lower hardness, change in order to prevent the material hardness, the choice of the highest temperature limit must be in a safe range.