DESCRIPTION: PARKER UP SERIES U-RINGS are non-symmetrical piston seals, and are designed to solve specific heavy duty hydraulic sealing problems. The back-beveled lip faces the bore where it will provide enhanced low-pressure sealing and wiping action on the bore surface. The non-symmetrical extended lip is used as a stabilizing element on the static sealing surface. The UP U-Ring is designed to be interchangeable with many styles and sizes of other PARKER PACKING piston seals, permitting direct substitution in the same grooves if problems arise. The back-beveled lips do not provide sealing in the reverse directions. These seals should be used only for unidirectional applications.
