Products

U-Cups

Ugly Part Relief Kit

Our Ugly Part Relief Kit is designed to alleviate headaches and stress around problematic parts in your supply chain.

Rubber U-Cups

Since our founding in 1956, Rothkopf has taken pride in finding our customers the rubber parts they seek, no matter how unique they may be. We’re confident that our deep roots in the industry coupled with our technical expertise will get you the right, best part. Learn more about U-cups below.

U-cups, or Lip Seals, as they are also called, perform well in rod, piston, reciprocating and some rotary applications. By design, as pressure increases, the “U” shape self-energizes to maintain sealing effectiveness. The U-cup can be used by itself, or an O-ring can be loaded within the U-cup to “energize” the seal performance at lower pressures. “Loaded” U-cups, commonly referred to as “PolyPaks,” are used in hydraulic applications.

U-cups are available in a variety of materials, such as polyurethane, nitrile rubber, and PTFE depending on the application requirements. That also applies to the O-rings used in loaded U-cups.

Dimensions—Inside Diameter, Outside Diameter, and Cross-Section—are always measured at the base of the U-cup.

There are many standard size U-cups available, some with asymmetrical lip configurations that meet specific application requirements. Reach out to Rothkopf today for assistance in selecting the right part for your application.