It consists of gate valve of metal-to-metal sealing and pneumatic actuator which is the operating part of SSV. When it works, the high-pressure draft flow into the upper cylinder chamber and compress the spring downward to open the valve. When the wellhead or pipeline pressure is higher or lower than the setting value, the cylinder releases pressure, the compressed spring then pushing piston upward, the valve is closed.
The pressure of the actuator comes from air compressor. The working pressure of the pneumatic actuator is 0.5-0.8Mpa. The actuator are suitable for all the pipelines including wellhead, the station which don’t have strict requirements for the working condition and service media.
The pressure of the actuator originates directly from flow pipe and the pipeline media ( including impure light oil, natural gas) goes into the actuator as pressure source after filtration. The pressure level, material class, specification level of the actuator is identical with the master valve.
Design Features:
l Pneumatic actuator installed on the top of the bonnet which controls the open / close of the valve by pneumatic pressure;
l Metal seal between the body and bonnet;
l Backseat seal between the stem and the bonnet, easy for the change of sealing stuff under pressure;
l Sealing surface is hard-faced or the QBQ with the performance of anti-corrosion, wear-resistance;
l Low operating torque
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