Hydraulic seals can be made from a variety of materials such as polyurethane, rubber or PTFE. The type of material is determined by the specific operating conditions or limits due to fluid type, pressure, fluid chemical compatibility or temperature. Other materials to consider depending on your application are Viton, NBR, EPDM, and filled PTFE.

Static :
A static hydraulic seal is located in a groove and sees no movement - only sealing within its confined space, acting like a gasket.To achieve this the gasket should be under pressure. The pressure is applied by tightening of the bolts.

Dynamic :
A type of dynamic hydraulic seal called a rod seal is exposed to movement on its inner diameter along the shaft or rod of a hydraulic cylinder. A type of dynamic hydraulic seal called a piston seal is exposed to movement on its outer diameter along the tube or bore of a hydraulic cylinder.