Parker Packing Division (EPS Division)

The U-Cup (U-Packing or U-Ring) is the most compact and versatile of the many lip type seals available.  In its several configurations, it may be utilized as an ID - Rod Seal, or an OD - Piston Seal.

The U-cup with long thin lips has very low dynamic friction and can accommodate out-of-round or eccentric components.  Other configurations with short heavy lips provide a more reliable seal at low pressures and are better suited for sealing at high pressures.  These variations in design, coupled with the broad range of available Parker materials results in a a very versatile line of sealing devices.

Parker Packing produces a full line of U-Cups ranging from standard AN geometry to the Parker BT U-Cup, a third-generation product with superior qualities.  Many U-Cups allow seepage, Parker's BT U-Cup however, includes a buffer ring, which keeps the primary seal dry through even the most stringent service. The unique BT U-Cup is made from Parker 4300, a new, low compression set polyurethane material which meets the requirements of most Original Equipment Manufacturer's specifications.

PolyPaks are patented, precision-molded, multi-purpose sealing devices combining an O-Ring type O-Spring with a conventional lip seal. This produces a unique product which seals in vacuum, high or low pressure.

The PolyPak design offers many unique advantages including superior sealability -- providing an excellent seal from hard vacuum to more than 60,000 psi*. The PolyPak won't leak under low pressure like many conventional U-Packing seals and maintains lip loading on the I.D. and O.D. interface during temperature extremes.

When combined with one of Parker's high performance urethanes or other sealing materials, the PolyPak is an unbeatable combination of unique design geometry and seal material capable of solving almost any hydraulic sealing problem.

Parker Rod Wipers are available in many styles and compounds.  The primary lip of a typical rod wiper provides a gentle but effective wiping action during each stroke of the cylinder rod to remove foreign material such as dust and grime from the exposed metal while still maintaining an adequate lubricating film on the rod to prevent excess wear on the primary seal.  It protects the rod from scoring and the primary seal from damage.