HangZhou Hoyee trade Co.,Ltd


Home > News > Content
Select Valve According To Prevent Medium Backflow
- Aug 30, 2018 -

The role of this type of valve is to allow only the medium to flow in one direction and to prevent the direction of flow.Usually the valve operates automatically, and the disc opens under a flow pressure in one direction.When the fluid is flowing in the opposite direction, the pressure of the fluid and the self-aligning disc of the disc act on the seat to cut off the flow.Check valves of this type include swing check valves and lift check valves.The swing check has a simple hinge mechanism and a door like disc that rests freely against the inclined seat surface.To ensure that the disc reaches the proper position of the seat face each time, the disc is designed in a hinge mechanism so that the disc has enough swing space and allows the disc to truly, fully contact with the seat.The disc can be made entirely of metal, either inlaid with leather, rubber, or with synthetic covering depending on the performance requirements.With the swing check valve fully open, the fluid pressure is almost unimpeded, so the pressure drop through the valve is relatively small.The valve disc of the lift check valve is located on the seat sealing surface of the valve body.In addition to the disc being freely lifted and lowered, the rest of the valve ACTS as a globe valve. Fluid pressure lifts the disc from the seat seal face, and backflow of media causes the disc to fall back onto the seat and cut off the flow.Depending on the conditions of use, the disc may be of all-metal construction or in the form of a rubber pad or ring inlaid on the disc shelf.Like globe valves, the flow through the swing check valve is narrow, so the pressure drop through the swing check valve is larger than the swing check valve, and the flow of the swing check valve is limited.