2021-05-03
1) The swing check valve has a pin structure and a gate like disc resting freely against the sloping seat surface. In order to ensure that the valve disc can reach the proper position of the seat surface every time, the valve disc is set in the pin structure, so that the valve disc has enough swing space, and makes the valve disc truly and well contact with the seat. When the swing check valve is fully opened, the fluid pressure is almost unimpeded, so the pressure drop through the valve will be smaller. The valve disc can be made of metal, or inlaid with leather, rubber or composite cover, depending on the requirements of the applicable function.
2) The valve disc of the lift check valve is located on the sealing surface of the valve seat on the valve body. In addition to the free lifting of the valve disc, the rest of the lift check valve is the same as the stop valve. The fluid pressure makes the valve disc lift from the sealing surface of the valve seat, and the medium backflow causes the valve disc to fall back to the valve seat and cut off the flow. Like globe valve, the passage of fluid through lift check valve is narrow, so the pressure drop through lift check valve is larger than swing check valve. According to the applicable conditions, the disc can be of all metal structure, or inlaid with rubber pad or rubber ring on the disc holder.