How to prevent the backflow valve of medium
Among them, the check valve belongs to this type of valve, which includes swing check valve and lift check valve. The swing check valve has a hinge mechanism and a gate like valve free against the inclined seat surface. In order to ensure that the valve can reach the appropriate position of the seat surface at any time, the disc is designed in the hinge mechanism so that the disc has enough swing space to make the disc real and comprehensive contact with the valve seat. The disc can be made of either metal or leather, rubber, or synthetic coverage, depending on performance requirements. The swing check valve is almost completely open and the fluid pressure is almost unimpeded, so the pressure drop through the valve is relatively small. The check valve of the lift check valve is located on the valve seat sealing surface of the valve body. In addition to this valve disc is free to lift, like the rest of the cut-off valve, the fluid pressure valve from the valve seat sealing surface lift, medium return led down to the valve seat, and cut off the flow. Depending on the service conditions, the disc can be of all metal construction or in the form of a rubber pad or rubber ring on the valve frame. The same as the cut-off valve, lift check valve fluid through the channel is narrow, so the check valve by lifting the pressure drop than the swing check valve a little bigger, and swing check valve flow restrictions very little.
The function of this type of valve is to allow the medium to flow in one direction and to prevent flow in the opposite direction. Usually the valve is automatically work, fluid pressure flow in one direction, the valve open; the opposite direction of fluid flow by gravity, fluid pressure and valve closing effect on the valve seat, thereby cutting off flow.
Check valve operating principleCheck valve refers to rely on the flow of the media itself and automatically open and close the valve flap, used to prevent the media back flow valve, also known as check valve, Dan Xiangfa, counter flow valve and back pressure valve. The check valve belongs to an automatic valve, whose main function is to prevent the backflow of medium, prevent the reverse of pump and drive motor, and release the container medium. The check valve can also be used to provide a supply to the auxiliary system where the pressure may rise above the system pressure. The check valve can be mainly divided into swing check valve (rotating by gravity center) and lift check valve (moving along the axis).