Diaphragm valve operating characteristics and performance

Diaphragm valve with corrosion-resistant lining of the valve body and corrosion-resistant diaphragm instead of spool assembly, the use of diaphragm movement from the regulation. Diaphragm valve body material made of cast iron, cast steel, or cast stainless steel, and lined with a variety of corrosion-resistant or wear-resistant materials, diaphragm materials, rubber and PTFE. The lining of the diaphragm corrosion resistance, suitable for strong acid, alkali and other corrosive media regulation. Diaphragm valve structure is simple, fluid resistance, flow capacity than the same size of the other types of valves; no leakage, can be used for high viscosity and suspended particulate media regulation. The diaphragm isolates the media from the upper chamber of the stem, so no media will not leak. However, due to diaphragm and lining material limitations, pressure resistance, temperature resistance is poor, generally only applies to 1.6MPa nominal pressure and 150 ℃ below. The flow characteristics of the diaphragm valve are close to the quick-opening characteristic, which is approximately linear before 60% of the stroke and little change after 60% of the flow. Pneumatic diaphragm valve can still be attached to the feedback signal, limiter and locator and other devices to adapt to automatic control, program-controlled or regulate the flow needs. Pneumatic diaphragm valve feedback signal using non-contact sensing technology. The product uses a membrane-propeller cylinder, instead of the piston cylinder, ruled out the piston ring is easily damaged, resulting in leakage can not promote the valve opening and closing of the drawbacks. When the air supply fails, the handwheel can still be operated to open and close the valve.