Control mode: According to the site condition has the following three kinds of control mode, the reasonable selection of the control Method can make your valves service life more longer, more convenient operation, cost savings.
Normally open type user: Suitable for pneumatic valve in the working time longer occasion. When the valve is normally open Spring does not load external gas source thrust, then the valve fatigue to a minimum. Because it is by the air pressure to Close valve, so need filed air pressure stability, air supply reliable.
Normally closed type user: Suitable for pneumatic valve is in the closed time working longer occasion. For depends on the Spring to close, when air pressure to drive the piston push spring, valve open. So for the normally closed user this valve Service life more long, gas more economical. At the same time when the air supply fails, the valve is in the closed state, This control state is the most widely used.
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