B-type loaded U-cup hydraulic seals are used for dynamic reciprocating applications. Sometimes called loaded-lip U-cups, B-style polypack, and lip seals, these seals have a beveled edge with a symmetrical cross section. They have a quad-ring loader that makes the seal a good choice for low-pressure rod applications. The sealing force compensates for high-pressure to maintain a positive seal.
Rod seals help prevent hydraulic fluid from leaking from the rod end of a hydraulic cylinder. In addition to keeping fluid from leaking, seals also help keep dirt and contaminants out of the cylinder, which extends the lifespan of the cylinder. Hydraulic rod seals are installed in a groove that has been machined in the cylinder housing to provide a tight seal against the piston shaft. Rod seals are used in mobile hydraulic, agricultural, and general industrial applications.