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U-Cup Seal Quote: Rod, Piston, and Hydraulic Cylinder Pricing
Quick Answer: A U-cup seal quote requires the rod diameter, bore diameter, groove width, groove depth, operating pressure, temperature, hydraulic fluid, and quantity. CORASEALS supplies standard and custom U-cup seals in polyurethane, NBR, FKM, and HNBR. Send the groove and cylinder data with a drawing or sample photo for a complete price.
U-cup seals are lip seals with a U-shaped cross section. They are used in hydraulic cylinders, pneumatic cylinders, rod sealing applications, and piston sealing applications. The seal lip responds to system pressure. The lip contacts the rod or bore and keeps oil inside while blocking dirt and moisture. The sealing function works only when the groove dimensions, material, and lip profile are correct.
Required Information for a U-Cup Seal Quote
A U-cup seal quote cannot be based only on a type code such as UN, UHS, or USH. These codes vary by catalog and manufacturer. CORASEALS uses dimensional data and material requirements to confirm the seal profile. The most important dimensions are rod diameter, bore diameter, groove width, groove depth, seal height, and radial depth. For piston seals, the bore diameter and groove diameter are critical. For rod seals, the rod diameter and housing bore are critical.
- Rod diameter or bore diameter
- Groove width and groove depth
- Seal height and radial cross section
- Operating pressure, including pressure spikes
- Operating temperature range
- Hydraulic fluid or pneumatic medium
- Speed or stroke frequency
- Required quantity
- Drawing, sample photo, or existing part number
- Material preference if known
U-Cup Seal Materials and Fluid Compatibility
The material choice changes the quote and the seal performance. Polyurethane is common for high wear resistance and extrusion resistance in hydraulic cylinders. NBR works with many mineral oils and water glycol fluids. FKM suits higher temperature and aggressive fluid conditions. HNBR offers good mechanical strength and heat resistance. EPDM is usually not recommended for mineral oil hydraulic systems. The quote should state the fluid type. A material can be selected only after the chemical compatibility is confirmed.
- Polyurethane
- NBR
- FKM
- HNBR
- EPDM for specific water or brake fluid applications
Metric and Inch U-Cup Seal Dimensions
U-cup seals are measured in metric and inch units. Some catalogs list OD x ID x height. Others list rod diameter x groove diameter x groove width. Specify the unit for every dimension. A drawing removes confusion. For example, a rod seal request may state rod diameter 40 mm, groove diameter 50 mm, and height 7 mm. The groove dimensions must still be confirmed against the cylinder hardware.
CORASEALS handles metric and inch requests. When you request a U-cup seal quote, send all dimensions in one unit system. If the drawing is in inches, include the inch values. If the drawing is in millimeters, include the millimeter values.
U-Cup Seal Types: Rod Seals and Piston Seals
U-cup seals include rod seals and piston seals. Some profiles have one lip. Some have double lips. Some are symmetric, and some have a secondary lip or back bevel. U-cup profiles can replace UN, UHS, USH, and similar codes only after checking the cross section and dimensions. Do not assume complete interchangeability based only on the type code. CORASEALS asks for the drawing or sample photo when a code-only request is unclear.
How to Request a U-Cup Seal Quote
A standard U-cup seal quote moves faster when the dimensions and fluid are clear. A custom U-cup seal quote needs a drawing, sample, or detailed groove sketch. The CORASEALS sales team checks the dimensions, material, pressure,