In modern fluid delivery systems, check valves are an important safety component responsible for preventing fluid backflow and ensuring the stability and safety of the system. However, the sealing performance of the check valve directly affects the effectiveness of its function. If the sealing performance is insufficient, it may cause fluid leakage, which not only wastes resources but also may cause safety hazards. Therefore, improving the sealing performance of the check valve is a key factor in ensuring the normal operation of the fluid system.

There are many ways to improve the sealing performance of the check valve, among which grinding the sealing surface is one of the most effective means. Due to the long-term use of the check valve, the sealing surface will be worn due to friction and pressure, resulting in a decrease in sealing performance. By finely grinding the sealing surface, the wear marks can be effectively removed, the sealing gap can be reduced or eliminated, and the finish of the sealing surface can be improved. The grinding process is usually divided into three stages: coarse grinding, medium grinding and fine grinding. Each stage requires precise control of the grinding pressure and time to ensure the best grinding effect. In addition, it is also crucial to select suitable grinding tools and abrasives to adapt to check valves of different materials and structures to achieve the best sealing performance.

In the process of improving the sealing performance of the check valve, using unbalanced force to increase the sealing pressure ratio is also an effective strategy. During the operation of the check valve, the sealing pressure applied by the actuator on the valve core is fixed. However, when the unbalanced force has a tendency to push the valve core open, the sealing force of the valve core will weaken; on the contrary, when the unbalanced force has a tendency to close, the sealing force of the valve core will increase. Therefore, by adjusting the structure of the check valve or adding auxiliary devices, the unbalanced force can exert a closing pressure on the valve core, thereby effectively improving the sealing pressure ratio. This method is particularly suitable for single-seal valves and two-position cut-off regulating valves, and can significantly improve the sealing effect.

In addition, enhancing the sealing force of the actuator on the valve core is also a common method to improve the sealing performance of the check valve. Common technical means include adjusting the working range of the spring, selecting a small stiffness spring, adding auxiliary equipment (such as a positioner), increasing the air source pressure, and replacing it with an actuator with a larger thrust. These methods can be flexibly selected according to the specific application scenario of the check valve to achieve the best sealing effect.

In addition to the above methods, the use of single seal and soft seal technology is also an effective means to improve the sealing performance of the check valve. For control valves with double seal structure, changing to single seal can usually improve the sealing effect by more than ten times. For hard-sealed valves, the use of soft sealing materials, such as rubber or polytetrafluoroethylene, can further improve the sealing effect, which can also achieve an improvement of more than ten times. This soft sealing technology not only enhances the sealing performance, but also effectively reduces the opening and closing force of the valve, thereby extending the service life of the valve.