Check valve also known as a valve or check valve, its role is to prevent the flow of media in the pipeline back. The bottom valve of water pump suction is also the check valve class. Forged STEEL Check valve has two kinds of body cover connection design form: The first is the body cover bolt connection forged steel check valve, in accordance with the design of the valve, the valve body and bonnet with bolts connected, wound gasket sealing, the advantages are easy to repair; the second type of body cover fully welded seal forged steel check valve, according to this type of connection designed valve, The valve body and the valve cover are connected with the screw mosquito, the whole weld seals, the advantage is no leakage.
Check Valve: According to the structure of the division, can be divided into lift check valve, swing check valve and butterfly check valve three kinds. Lift check valve can be divided into vertical and straight-through two types. Swing check valve is divided into single, double and multiple three kinds of type. Butterfly check valve is butterfly type double, butterfly type single, above several check valve in the connection form may divide into the threaded connection, the flange connection, the welding and to the clip type connection four kinds.
Check valve refers to the flow of the media itself and automatically open, close the disc, used to prevent the backflow of the valve, also known as the reverse valve, check valves, countercurrent valve, and back pressure valve. Check valve belongs to an automatic valve, its main role is to prevent the media backflow, to prevent the pump and drive motor reversal, as well as the container media release. The check valve can also be used to provide a pipeline where the pressure may rise to an auxiliary system that exceeds the system pressure. Check valves can be divided into swing check valve (according to the center of gravity rotation) and lift check valve (along the axis movement).
Check valves This type of valve has the effect of allowing only the medium to flow in one direction and preventing the flow of the opposite direction. Usually this valve is operated automatically, in one direction flow pressure of fluid, the disc opens; When the fluid is in reverse direction, the valve flap is operated on the valve seat by the weight of the fluid pressure and the disc, thereby cutting off the flow.
The check valve belongs to this type of valve, which includes a swing check valve and a lift check valve. The Swing check valve has a hinge mechanism and a door-like disc is freely propped against the tilted seat surface. In order to ensure that the disc can reach the proper position of the seat face each time, the disc is designed in the hinge mechanism so that the disc has enough swing space and the disc is truly and fully in contact with the seat. The disc can be made entirely of metal, or it can be inlaid with leather, rubber, or synthetic coverage on metal, depending on the performance requirements. The Swing check valve is completely open, the fluid pressure is almost unimpeded, so the pressure drop through the valve is relatively small. The valve flap of the lift check valve is located on the valve seat seal face on the body. This valve, in addition to the free movement of the disc, the rest is like a cut-off valve, fluid pressure to lift the disc from the seat sealing surface, the media backflow causes the disc to fall back to the seat, and cut off the flow. According to the conditions of use, the disc can be a all-metal structure, or it can be the form of a rubber pad or rubber ring on a disc rack. Like a cut-off valve, the fluid passes through the lift check valve is also narrow, so the pressure drop ratio of the lift check valve is larger than the swing check valve, and the flow of the swing check valve is limited.