Crosshead U-Cup Seal

A high durometer polyurethane U-cup that fits into the intensifier crosshead, sealing the interface between the hydraulic piston rod and the crosshead bushing. Its twin lips flex outward under pressure to block hydraulic oil while the precision-molded heel resists extrusion during every 3,000 psi stroke reversal. Swap this seal at each minor service to keep oil out of the water end and preserve accurate stroke timing.

Related Products:

• Seal-Carrier Assembly 55K (013933-1) — stainless pocket that surrounds the crosshead U-cup and dynamic seals.
• Dynamic High-Pressure Seal 5⁄16 ID HDS White (011051-1) — PTFE primary seal that runs directly against the ceramic plunger.
• Rod Seal Nitrile 5⁄16 ID × 9⁄16 OD (A-00720-31) — rear wiper that keeps hydraulic oil from the water end.
• Hytrel® Back-Up Ring 0.248″ ID (006760-1) — supports the dynamic seal against extrusion at full load.
• HyPlex Minor Maintenance Kit (712101-1) — bundles U-cup, dynamic seals, back-up rings and rod seals for the 500-hour service.

Service tip: install the new U-cup dry on its OD and lightly oil the lips; torque the seal carrier to spec so the lips preload correctly.