Lift check valve disc in disc, seat around tunnel axis rotation, due to the channel into a streamline in the valve, flow resistance is smaller than l butterfly check valve, suitable for low flow velocity and flow not often change the large diameter of occasions, but should not be used for oscillating flow, its sealing performance than lift. Butterfly check valve points single type, double disc type and for the most part three, the three forms mainly by the valve diameter, the purpose is to prevent the backflow medium flow or stop, decrease hydraulic shock.

Lift check valve: disc along the vertical centerline of sliding body check, internal thread check valve can only be installed in horizontal pipe runs with the high pressure small check valve disc can be used on the ball. Butterfly check valve body shape and cut-off valve with cut-off valve (gm), so its flow resistance coefficient is larger. Its structure is similar to cut-off valve, valve body and disc is the same as the cut-off valve. Disc upper part and lower part of the cover processing has a guide sleeve, Jane Jane disc guide can be freely within the valve light guide Jane, when the downstream of the medium, the disc by medium thrust open, when stop the flow of medium, the disc landing on the hanging on the seat, to prevent medium counter-current role. Straight-through butterfly check valve medium import and export channel direction and seat vertical direction; Vertical lift check valve, import and export of its media channel direction and seat in the same direction, its a straight-through flow resistance is small.

Lift check valve: disc around the seat of pin shaft rotate within the check valve. Disc check valve has simple structure, can only be installed in horizontal pipe runs, sealing is good.

Lift check valve: disc sliding along the center line of the body of the valve. Pipeline check valve is a new kind of valve, its small size, light in weight and good processing technology, is one of the check valve development direction. But the fluid drag coefficient is slightly superior to swing check valves.

Compression type check valve: the valve is used as boiler feed water and steam to cut off the valve, it can lift check valve and globe or Angle valves integrated function.

In addition, there are some is not suitable for pump discharge to install the check valve, such as the bottom valve, spring loaded, Y type check valve, etc.