notice of ball valve appliance situation
[author：topsvalve] [date：10-07-14]
[heat：]
Due to rubber, nylon and PTFE are used as seat sealing ring in ball valve, therefore its use is subject to seat seal material temperature .Ball valve ‘s function is to use the pressure from the service, pushing the metal sphere to clamp the plastic seat(floating ball valve).seat sealing ring under certain contact pressure to cause it elastic-plastic deformation in local regions. This distortion can compensate sphere’s manufacturing accuracy and surface roughness, guarantee the valve sealing performance. And since the ball valve seat sealing rings are usually made of plastic, so when selecting the ball valve structure and performance, we have to consider keeping ball valve fire endurable and fireproof. For areas like petroleum, chemical industry, metallurgy, when ball valves are used in flammable ,explosive service equipment and pipeline systems, more attention should be paid for fire endurable and fireproof
Usually，ball valves are recommended to use in such piping systems as follows:
Two-position control, strict sealing, slurry, wear, reduced access, quick opening and closing action (1 / 4 turn to open and close), high pressure cut-off (large pressure), low noise, phenomenon of cavitation and gasifica
Ball valve is also applied in the pipeline system which is of light-type structure, low pressure cut-off (little differential pressure), corrosive service. Additionally, in the low temperature (deep and cold )environment and pipeline system, ball valve is also acceptable. In the metallurgy field, it should use the seriously degreased ball valve in the oxygen pipeline system. When the main pipeline of the oil pipeline and gas pipeline is inbuilt underground, it should use the full-port welding ball valve. If it requires regulating performance ,it is best to choose the V shape open end special nonstructural ball valve. In the field of petroleum ,petrochemical,chemical,electrical,urban construction, we also can choose ball vale sealed with metal to metal, undergo temperature above 200℃.