Hydraulic lip seals is a self-sealing seal that relies on the lip to fit the surface of the sealing coupling and block the leakage channel to achieve the sealing effect. When the medium pressure increases, the medium is squeezed in the middle of the lip, making the lip fit the sealing surface more closely to increase the sealing performance.Hydraulic lip seals are generally used as dynamic seals, such as reciprocating or rotary motion, and are commonly used in hydraulic and pneumatic systems.