Check valve. Check valves are the same, but they are called differently. According to the common parlance in various regions. In fact, they are the same valve. All are check valves. Check valves have a wide range of applications and many types. The following are the commonly used check valves for water supply and heating:
1. Spring type: The liquid rises from bottom to top. The valve disc controlled by the spring is lifted by pressure. When the pressure disappears, the spring force presses the valve disc down, blocking the backflow of the liquid. It is often used for check valves with smaller diameters.
2. Gravity type: Similar to the spring type, it relies on the self-weight of the valve disc to seal and prevent backflow.
3. Swing type: The liquid flows directly into the valve body and is pushed open by pressure on one side of the rotating valve disc. When the pressure is lost, the valve disc returns to its original position by its own weight, and the reverse liquid pressure closes the valve disc. The principles of other check valves (check valves), such as those for sewage discharge, explosion-proof valves for civil air defense, and check valves used for liquids, are largely the same
