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U Cup Seals

U-cup seals are named after their “U” shaped profile formed due to their distinctive cross-section. These seals are suited for high-pressure applications because the U shape of the seal energizes the seal lips at high pressures. U cup seals are ideal for static and dynamic applications. Being a leading U cup seal manufacturer, we perfectly understand client requirements and provide these seals in unique configurations. We can customize them to meet your application requirements.

U-Cup Seal Designs

The following are some standard U-seal designs provided by us.

Loaded U-Cup Seals
These seals feature an O-rings loader, which makes them an excellent sealing option for piston and rod applications. The force on the seal’s loading lips increases with the system pressure. When this happens, the sealing force compensates for the pressure automatically and maintains the sealing. It is a single-direction seal, which can pressure seal in one direction. As the sealing is unidirectional, the two U-cups must be installed in two directions for piston applications. The loaded U-cups are rectangular and this adds stability to its sealing function.		 Loaded U Cups
Spring Energized U-Cups
These U-cups feature energized metallic spring, thus, the name. Spring energized U-cups are used in dynamic applications because the spring helps load the lips of the seal against mating surfaces.		 Spring Energized U Cups
Unloaded Urethane U-Cups
This cup has no O-ring and is suited for dynamic and static applications. It is ideal for rod and piston applications and is also known as Disogrin U-cup. Unloaded U-cups are compact-sized and more appropriate for applications where small spaces are involved. Our unloaded U-cups find applications that are used in low-pressure and low-speed environments for hydraulic and pneumatic seals.		 Unloaded Urethane U Cups
Homogenous U-Cups
These U-cups are more commonly used for pneumatic applications. They are non-loaded, made from a single material, and are ideal for applications operated at low pressure.		 Homogenous U Cups

U Cup Box

A u-cup is an o-ring formed into a u-shaped channel. Liquid or air pressure "inflates" the u-cup and affects a seal. The u-cup is ideal for use on linear moving shafts and piston heads, because unlike an o-ring the shape does not try to roll with the movement and create friction. The sides of the u-cup allow the shaft to move virtually unhindered, and seal with a wiping action.

U-Cup Seal Materials

We provide U-cup seals created from the following materials.

  • Nitrile: The seals made of this material show exceptional wear resistance and resilience. Nitrile U-cup seals can be used safely in a broad range of temperatures from -40°F to 248°F.
  • Polyetrafluorethylene (PTFE): The seals provide virtually universal chemical, wear, and cold flow resistance. PTFE seals are suited for a broad temperature range from -450°F to 450°F.
  • FKM (Fluorocarbon Rubber): Our FKM U-cup seals are used in applications exposed to high temperatures, various types of chemicals, and harsh weather. They are also known for their proven aging and weather resistance. You can operate these seals in temperature ranges from -15°F to 400°F.
  • Ethylene Propylene Rubber (EPDM): The U-cup seals made from this material can resist hot water, steam, aging, and ozone. It is suited for temperature ranges from -65°F to 302°F.
  • 15% Glass Filled PTFE: The seals made of this material showcase excellent tensile and compression strength, wear resistance, and cold flow resistance. These seals can be operated in temperature ranges from -450°F to 550°F.
  • 40% Bronze Filled PTFE: These seals display excellent hardness and low friction. These seals work best in the temperature ranges from -450°F to 550°F.
  • 25% Carbon Graphite Filled PTFE: The U-cup seals showcase increased hardness, increased wear resistance, and low friction. These seals are best for the temperature ranges from -450°F to 550°F.


U-Cup Seal Selection Criteria

At SSP Seals, you can find a broad collection of U-Cup seals. Choosing the right seal for your application can be challenging at times. Several factors such as media, extrusion gap, resistance to wear and tear, and resistance to temperatures must be addressed. Here are some general factors to consider when buying these seals.

  1. Pressure of the System: The seals are an integral part of several manufacturing equipment. This equipment is operated at a certain pressure range. Hence, ensure to choose the seal that can withstand the pressure range, without the risk of failure. The pressure rating of the seal is calculated based on the test temperature of 70°C/160°F. When considering the pressure, ensure to address the extrusion gap.
  2. Fluid Media: Sealing surfaces may contact various chemicals during the operation. Check the chemical compatibility of the sealing material to ensure its proper functioning.
  3. Seal Life Expectancy: The seal’s performance depends on factors such as stroke, duty cycle, surface finish, speed, performance, and fluid type. In addition to this, the expectancy of the seal will depend on the material chosen. Each material possesses a specific pressure/velocity. The price range also varies for materials with a long lifespan.
  4. Retrofit and Gland Size: Most manufacturers offer these seals in standard sizes. We can provide them in custom sizes to meet your application requirements
  5. Installation: The seal installation must be considered when choosing the U-cup seal. Installation of the seals will vary depending on the size, profile, material, and application.
  6. Ancillary Performance: The following are some criteria to be considered when choosing a U-cup for your application.

    The following are some criteria to be considered when choosing a U-cup for your application.

    • Does the application require sealing with a high level of friction?
    • Does the seal require resistance from contamination?
    • Does the current design assure stability?

Contact us to learn more about U-Cup seals or call +1-888-238-SEAL to get immediate answers to your question.


lip seals