Hydraulic systems are often used in mobile applications, such as excavators, fork-lift trucks and bulldozers. Hydraulic systems also are often used in heavy industry. Great attention is paid to efficiency and leaks are to be avoided at all times. The reduction of noise is also of great importance. The hydraulic seals have to meet high standards.To meet these high standards hydraulic seals often are made of a combination of high quality sealing designs.
For example, piston seals are used in hydraulic cylinders. They are internal to the cylinder head, preventing fluid from flowing across the cylinder head. This ensures pressure build up on one side of the piston, making the cylinder extend or retract.