U Cup Seals for Heavy Duty Applications
1800seal911 / EPM'S u-cup seals can be fabric-reinforced for heavy-duty applications that involve slow-moving rams and pistons, for example, those used in hydraulic presses, jacks and cylinders. Our u-cup seals are easy to install and require less space thanks to a heel clearance for minimum friction and positive lip interference, which provides the initial seal at low pressures. When fabric-reinforced, our u-cup seals typically work best in applications requiring pressures of up to 3,000 psi, although they can be effective at higher pressures provided there is minimal clearance between the metal parts. A fabric-reinforced u-cup is best installed with a pedestal, or, a pedestal and back-up cushion ring. The pedestal, which keeps the u-cup seal's lips away from the bottom of the gland, doesn't exert radial pressure on the lips. As a result, the molded-in lip interference provides the initial seal and the pressure needed to actuate the lips. The elastomer binder delivers the "memory" required to maintain lip contact at all pressures.