Lip seals: such as Y-type seals, V-type seals, etc. They rely on the lips to close to the surface of the piston rod to achieve sealing and can adapt to certain pressure and speed changes.

Combined seals: such as Glyer rings, Step seals, etc. It is usually composed of an elastomer seal and a wear-resistant ring such as polytetrafluoroethylene, with good sealing performance and wear resistance.

Mechanical seal: The seal is achieved by the close fit of dynamic and static rings, which is suitable for high-speed, high-pressure, and high-temperature working conditions.