Gaskets, Seals, O-Rings & Elastomer Components worked example

Compression Set Margin at 35% allowed compression set limit: a worked example

Push allowed compression set limit up to 35% and the picture changes. This example computes every intermediate figure at that operating point. Use it when product engineering or quality needs to confirm that silicone, EPDM, nitrile, neoprene, polyurethane, or FKM seals still have enough compression recovery margin after aging, heat exposure, or validation testing.

The inputs for this scenario

  • Allowed compression set limit: 35 % (raised for this scenario; the documented default is 30)
  • Measured compression set: 22 % (unchanged)
  • Compression set reference basis: 100 % (unchanged)

Working through the calculation

  • Applying the documented formula (Compression set margin points = allowed compression set limit - measured compression set) to the inputs above produces each figure below.
  • At this operating point the engine returns 13 % for compression set margin, the number this scenario is built around.
  • At this operating point the engine returns 13 value for compression set margin points.
  • At this operating point the engine returns 35 value for allowed compression set limit.
  • At this operating point the engine returns 22 value for measured compression set.

How this compares with the baseline

  • Against the tool's baseline example, where allowed compression set limit sits at 30% and the headline result is 8 %, this scenario comes in 62.5% above the baseline at 13 %.
  • It computes the gap between the allowed compression set limit and the measured compression set, both as raw points and as a percentage of a reference basis. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Compression set margin: 13 % (headline result)
  • Compression set margin points: 13 value
  • Allowed compression set limit: 35 value
  • Measured compression set: 22 value

Run it with your numbers

  • Every input above is editable in the live Compression Set Margin calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.