Working principle of pneumatic three piece ball valve: the pneumatic three piece ball valve can be closed tightly only by 90 degree air rotation and very small rotating torque. The completely equal inner cavity of the valve body provides a straight flow passage with little resistance for the medium. It is generally believed that ball valves are most suitable for direct opening and closing, but recent development has designed ball valves to be used for throttling and flow control. The main characteristics of the electric control valve pneumatic three piece ball valve (ball valve) are its compact structure, easy operation and maintenance.

Tips for prolonging the service life of pneumatic butterfly valve
For the pneumatic butterfly valve requiring heat tracing and insulation, two pneumatic butterfly valves with smaller diameter and equal length are generally selected for the heat tracing pipe, which are respectively placed at the lower left side and the lower right side, and they are bound together with glass cloth. In order to avoid wetting, the surface can be coated with ground water layer, or a waterproof iron shell cover can be specially made, but it shall not affect its compensation displacement.
During operation, strict procedures must be followed. There are many cases of destruction of pneumatic butterfly valve ripple compensator caused by starting the pump when the valve in front of the tank is opened. This must arouse attention.
Safety inspection shall be stopped every year for pneumatic butterfly valves and corrugated compensators in use. Remove them from the system pipeline. After cleaning, conduct a hydraulic test at 1.5 times of the working pressure for 10 minutes. After drying or drying, conduct a pneumatic test at 1 time of the working pressure for 15 minutes. Leakage is not allowed. At the same time, its appearance shall not show some abnormal phenomena such as the fracture of steel strip of mesh sleeve or the scattering of nuts.
When the pneumatic butterfly valve or corrugated compensator works to the lower limit position, it is not clear that its compensation can be used up. If it is necessary to replace the large compensation, the compensation can also be stopped by reducing the height of the connecting pipe mouth. Although all hoses or corrugated compensators have not yet worked to the lower limit position, they have been used for many years and must be replaced. Generally speaking, pneumatic butterfly valves or corrugated compensators connected to crude oil tanks and heavy oil tanks generally work for 8-10 years in inland areas and 5-8 years in coastal areas; pneumatic butterfly valves or corrugated compensators connected to storage tanks of light oil and other flammable and explosive media generally work for 5-8 years in inland areas and 3-5 years in coastal areas. As for the application sites with strong corrosion and erosion, in addition to special requirements on data, corresponding structural changes should be made. Their retirement period should be determined according to the detailed situation.
Good maintenance and home care is a necessary condition to ensure the safe operation of pneumatic butterfly valves, corrugated compensators and various storage tanks. Relevant staff must pay attention!