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 This calculator allows you to find the recommended O-Ring inner diameter and range of cross section diameters that will fit a given gland size and tolerance range in a radial seal.
Inputs
 Bore diameter, Bd: mm cm in Bore Tolerance, Btol: mm cm in Groove Diameter, Gd: mm cm in Groove Tolerance, Gtol: mm cm in O-Ring maximum compression, Cmax: % O-Ring minimum compression, Cmin: % O-Ring cross-section diameter tolerance, CStol: mm cm in
 Max. cross-section diameter (excl. tol.), CSmax: 0.068  in mm cm in Min. cross-section diameter (excl. tol.), CSmin: 0.065  in Your input CS tolerance, CStol: 0.003  in Industry-recommended CS tolerance: 0.003  in Recommended O-Ring inner diameter, IDrec: 0.392  in Suggested groove width, GW: 0.103  in

Equations Behind the Calculator
 This calculator implements the following two equations to determine the bounds on the cross-section diameter CS, The recommended tolerance is based on the cross-section diameter, and is found from the following table:
 Cross Section Diameter (inch) Recommended Tolerance(inch) CS < 0.104 0.003 0.104 < CS < 0.139 0.004 0.139 < CS < 0.210 0.005 0.210 < CS < 0.275 0.006 0.275 < CS 0.008
 The recommended inner diameter is found by stretching the O-Ring circumference by 2% over the minimum Groove Diameter, The suggested groove width follows from, More information is provided on the Design Guideline page.
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