English
What is a check valve
Check valve relies on its own weight and medium pressure to block the back flow of the medium. It is an automatic valve, also known as one-way valve, return valve or isolation valve. Its opening and closing parts are circular discs. The movement of the disc is divided into lift type and swing type.
The lift check valve is similar in structure to the stop valve, but lacks the valve stem that drives the disc. The medium flows in from the inlet end and flows out from the outlet end. When the inlet pressure is greater than the sum of the weight of the disc and its flow resistance, the valve is opened. On the contrary, the valve is closed when the medium flows back.
The swing check valve drives a disc rotating around the axis through the valve stem, and its working principle is similar to that of the lift check valve. The disadvantage is that the resistance is large and the sealing performance is poorer when closed.
The lift check valve is similar in structure to the stop valve, but lacks the valve stem that drives the disc. The medium flows in from the inlet end and flows out from the outlet end. When the inlet pressure is greater than the sum of the weight of the disc and its flow resistance, the valve is opened. On the contrary, the valve is closed when the medium flows back.
The swing check valve drives a disc rotating around the axis through the valve stem, and its working principle is similar to that of the lift check valve. The disadvantage is that the resistance is large and the sealing performance is poorer when closed.
