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Plastic check valveThe check valve functions and features The check valve is a kind of force according to the medium itself automatically opening and closing of the valve. The check valve is designed to prevent the reverse flow of medium. When the water flow in the opposite direction, the check valve is closed. Structurally, the check valve is generally divided into lift check valve and swing check valve two kinds. Lift check valve (stop-check valves) : lift check valve disc generally along the vertical center line of the check valve body movement. Lift check valve can be divided into two kinds of models, the horizontal and vertical. Lift check valve by valve body, valve cover, stem, seat and the valve core. Swing check valves (pivot type check valve) : swing check valve disc is usually revolve around pin shaft outside the seat. Swing check valves can be divided into three types of single, double valve, valve. Pivot check valve by valve body, valve cover, shaft and disc. The working principle of the check valve is vary according to the pressure of the fluid itself dynamic opening and closing, prevent the reverse flow of medium. Mainly used for water supply pipeline. Suction bottom valve is a check valve. Elevating suction bottom valve sealing, low noise, is generally used in nominal diameter less than 200 mm in horizontal pipe runs. Swing bottom valve seal bad absorption, noise big, generally used for vertical or large diameter pipeline. Suction bottom valve installed in the pump suction pipe, with bolt or flange and pipe connection. The characteristics of the commonly used check valve Disc check valve disc is revolve around the seat of the pin, its structure is simple, the sealing is poor, can only be installed in horizontal pipe runs. Pipeline check valve disc sliding along the centerline of the body. Lift check valve disc sliding along the center line of the body and can only be installed on a high level of pipeline fluid resistance coefficient. Swing check valve pin rotating disc around the seat. |