Because the pneumatic three-way ball valve usually uses rubber, nylon and polytetrafluoroethylene as the seat sealing ring material, its use temperature is limited by the seat sealing ring material。The cutoff function of the ball valve is completed by pressing the metal ball ball between the plastic seat under the action of the medium (floating ball valve)。Elastoplastic deformation occurs in some areas under the action of the contact pressure of the valve seat sealing ring。This deformation can compensate the manufacturing accuracy and surface roughness of the ball and ensure the sealing performance of the ball valve。
And because the valve seat sealing ring of the pneumatic three-way ball valve is usually made of plastic, it is necessary to consider the fire resistance and fire resistance of the ball valve in the selection of the structure and performance of the ball valve, especially in the petroleum, chemical, metallurgical and other departments, and the use of the ball valve in the equipment and piping system of flammable and explosive media, more attention should be paid to fire resistance and fire protection。
Generally, ball valves are recommended in two-position adjustment, strict sealing performance, mud, wear, shrinking channels, rapid opening and closing action (1/4 turn opening and closing), high pressure cutoff (large pressure difference), low noise, cavitation and gasification phenomenon, small leakage to the atmosphere, small operating torque, and small fluid resistance pipeline systems。
Pneumatic three-way ball valve is also suitable for lightweight structure, low pressure cut-off (small pressure difference), corrosive media piping system。Ball valves are also available in low temperature (cryogenic) devices and piping systems。In the oxygen piping system of the metallurgical industry, ball valves with strict degreasing treatment are required。When the main line in the oil pipeline and gas pipeline needs to be buried underground, the full-diameter welded ball valve should be used。Ball valves with V-shaped openings should be used when regulating performance is required。In petroleum, petrochemical, chemical, electric power, and urban construction, metal-to-metal sealed ball valves can be selected for piping systems with operating temperatures above 200 degrees。
Pneumatic three-way ball valve common faults and solutions:
Ball valve has been washed by materials for a long time, resulting in friction, causing serious impact wear, can not meet the normal production, and caused the shortening of the use of equipment。At present, many materials are used for ball valve wear, such as ceramic materials, polymer composite materials and other methods, and more Mei Jiahua technical system is applied。The polymer material has superior adhesive properties, which solves the disadvantages of frequent wear of metal and ensures the normal production of enterprise equipment。Moreover, the special ceramic material and special surface strengthening agent in the material make it better than any steel or even ceramic tile in the harsh dry grinding environment and physical impact resistance, and the incompatibility between the product and coal is the ideal material to prevent coal accumulation。
