Scraping and/or sealing element; Method for sealing a piston and a tensioning and/or a supporting element

摘要

The sealing unit has a seal (17) held in a groove of a housing (10). The seal has a quad ring (22) with four square cross section sides. The quad ring is arranged in the groove so that a lip of the quad ring is in contact with a piston (11) and another lip is sealingly in contact in the groove. The groove is provided with a shoulder that extends or is stepped when viewed in a radial direction of the piston. An independent claim is also included for a process for sealing a movable piston.