The check valve working principle analysis of how to prevent the backflow medium

The role of the non-return valve is only allowed to medium flows in one direction, the direction and stop the flow. The check valve is normally automatic work, in a direction of flow of fluid pressure, the valve disc to open; In the opposite direction of fluid flow, the fluid pressure and valve disc from the overlap of the valve disc on the valve seat, thereby cutting off flow. The check valve is belong to this type of valve gate, which includes swing check valve and lift check valve. Swing check valve with the humble hinge institutions, there is also a freely like the door of the valve disc on the tilt of the valve seat surface. In order to ensure that the valve disc to reach every time on the surface of the valve seat appropriate location, in valve design hinge agencies, in order to have enough plug valve kai xuan space, and make the valve valve genuine and comprehensive engagement with the valve seat. All valve disc can be made from metal, can be embedded in the metal on leather, rubber, or synthetic coverage, depending on the use of performance requirements. Swing check valves in the fully open conditions, almost unimpeded fluid pressure, so the pressure drop through the valve door is relatively small. Lift check valve flap valve is located on the check valve valve body valve seat sealing surface. The gate valve in addition to the valve disc is free to lift, like the rest of the cut-off valve, the pressure of fluid from the valve disc of the valve seat sealing surface lift, medium return led to back to the valve seat valve disc, and cut off the flow. According to the conditions of use, the valve valve can be all-metal structure, it can also be embedded in the valve disc shelves rubber mat or rubber ring form. Like a cut-off valve, fluid through the lift check valve channel is narrow, so the lift check valve through the pressure drop than the swing check valve is big, and swing check valves are very few restrictions.