O-ring/back-up ring combinations have long been considered the industry standard for static applications at high pressures. In field use, however, they may show weaknesses with respect to their installation and operation in the application. Standard O-rings are often prone to twisting, while back-up rings are oftentimes not installed in the proper position or damaged during installation. Furthermore, this sealing combination may exhibit deficits when exposed to pulsating pressures and dirt. Parker has developed the HS radial seal profile as a viable alternative to to conventionally used O-ring/back-up ring combinations for static sealing applications at high pressures.
The robust symmetrical seal geometry and use of particularly extrusion-resistant Parker polyurethane compounds not only simplifies installation but also enhances the sealing effect in pulsating pressure conditions. As a result, service life is significantly extended.