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Polyurethane U-Seal, 3.13 Inch OD, 2.50 Inch ID, 0.31 Inch Height
Brand
Hercules Sealing Products
Brand
Hercules Sealing Products
Supplier Part Number
U31-2.50
Alternate Part Numbers
Alternate Part Number
C1DQ16
got a cylinder that takes a 2.50 inch rod seal, are these u-seals sized by the ID or the OD?
Question by: Jimmy T on Mar 19, 2026, 12:58 PM
For this U-seal, the key sizing callout is the 2.50 inch ID, with a 3.125 inch OD and 0.3125 inch height. If your groove and hardware are set up around a 2.50 inch inner diameter seal, those dimensions line up with this part.
Answer by: Customer Support on Mar 21, 2026, 6:47 AM
What’s the deal with the lip on this thing, does it actually do anything special?
Question by: Danny P on Sep 19, 2025, 9:06 AM
The beveled lip design on this U-seal helps it break the fluid film, providing a more effective seal.
Answer by: Customer Support on Sep 21, 2025, 7:34 AM
Got a cylinder bore of 2.50 inches and need a U-seal that'll hold up past 3,000 PSI. This one gonna cut it?
Question by: Lance W on Mar 13, 2026, 11:36 AM
For a 2.50 inch bore, the inner diameter on this seal matches up right. Pressure-wise, it's rated from 0 all the way to 6,000 PSI, so 3,000 PSI sits well within its working range. The urethane construction handles that kind of load without giving out prematurely, and the beveled lip helps maintain a consistent film across the sealing surface under pressure.
Answer by: Customer Support on Mar 15, 2026, 6:43 AM
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