The check valve characteristic application and structure principle

Check valve is refers to the open-close part for the circular disc and and medium pressure action on its own weight to block medium backflow of a valve. Belong to automatic valve class, also called non-return valve, check valve, backflow preventer, or the isolation valve. The disc movement way into lift and swing. Lift check valve and globe valve structure similar, only the lack of drive disc of the valve stem. Medium from the inlet side ( Underside) Inflows from outlet ( Upper) Flow out. When the inlet pressure is greater than the weight of the disc and its resistance to flow, the sum of the valve is open. Characteristics of non-return valve application 1, use the 'bullet' modelling design, the appearance of a 'drum' fuselage design, improve the media flow valve, reduce the flow resistance coefficient of 2, use short forms of the valve structure, although the head loss than silent check valve lift are slightly larger, but the small size, price cheap 3, compact structure, between the guide shaft and guide frame to provide lubrication non-metal sleeve, valve lift and flexible, it won't produce 4 lock phenomenon, installed directly in the main body skeleton rubber seals, avoid long tao media directly to seal, significantly longer service life and durable 5, open and close short journeys, valve, which can effectively prevent water hammer 6, suitable for water supply and drainage system, high-rise building network, can be installed in the pump export, this structure has been changed, and can be used as the bottom of the suction valve, but not for the sewage pipe network. Structure principle 1, valve in use, according to the medium flow direction of the arrow. 2, when the medium, according to a predetermined direction flow by the role of media power valve, conduction; When upstream medium, owing to the valve and the weight of the media back valve, valve and valve seat sealing surface density close together, in order to prevent the medium counter-current purpose. 3, the body and the welding of stainless steel valve sealing surface mining. 3, the valve structure according to JB/T79 - The provisions of the GB12221-1994 1989 of the regulation, the length of the size of the flange.