The Introduction of Ball Valve Applications
Since ball valve usually uses rubber, nylon and PTFE as sealing ring materials of the valve seat, its operating temperature is limited by the sealing ring materials of the valve seat. The shut-off effect of sanitary ball valve is achieved by metal sphere pressing tight against the plastic valve seat under the effect of the medium. Under certain contact pressure, part of the sealing ring of the valve seat has plastic deformation. This kind of deformation can compensate for the manufacturing precision and surface roughness of the sphere, ensuring the sealing performance of the ball valve.
Since the sealing ring of the ball valve seat is usually made of plastics, when choosing the structure and performance of the ball valve, the fire-resistance and fire-proof need to be considered, especially in petroleum, chemical, metallurgical and other departments. When using ball valves in equipment and pipeline systems of flammable, explosive media, fire-resistance and fire-proof should be paid more attention to.
In general, ball valves are recommended to be used in pipeline systems of double-position regulation, strict sealing performance, mud, wear, necking channel, quick opening and closing, high pressure shut-off, low noise, cavitation and gasification, small leakage to atmosphere, small operating torque, small fluid resistance.
Ball valves are also suitable in pipeline systems of light structure, low-pressure shut-off, corrosive medium. Ball valves can also be used in low temperature devices and pipeline systems. In the oxygen pipeline systems of metallurgical industry, ball valves that have been through strict degreasing treatment need to be used. When the main pipeline needs to be buried underneath ground in oil pipelines and gas pipelines, full diameter welded ball valves need to be used. When there’s a requirement for regulating performance, special ball valves with V-shaped opening need to be used. In oil, petrochemical, chemical, electric and urban construction, metal-to-metal sealing ball valves can be used in pipelines with operating temperature of over 200 degrees Celsius.