In the hydraulic system and its systems, seals used to prevent leakage of the working medium and the intrusion of external dust and foreign matter. Which the seal components, namely seals.

　　Leakage will result in media waste, pollution machines and the environment, and even lead to malfunctioning machinery and equipment, personal accident.

　　Leakage within the volumetric efficiency of the hydraulic system will cause a sharp decline, reaching less than the required working pressure, can not even work.

　　Invade the tiny dust particles in the system, can cause or exacerbate friction wear of hydraulic components, and further lead to leakage.

　　Thus, seals and seals of hydraulic equipment is an important part. It's the reliability and service life, is a measure of the hydraulic system, an important indicator of good or bad.

　　In addition to clearance seal, the seals are used, the coupling between two adjacent surface of the gap between the need to control the liquid through sealed minimum clearance below.

　　In the contact seal, the seal pressed into self-sealing and self-sealing self-tight seal (lip seal that is) two.