How to: Measure Hydraulic and Pneumatic Seals

Watch our video which demonstrates how to size a variety of seals.

1. First identify your seal profile

By looking at the cross section of a seal and match it against a seal profile chart. Download our seal profile catalogue here.

2. Measure the seal's Outer Diameter (OD), Inner Diameter (ID), width and height.

Often the dimensions are printed on the seal. If not, you can measure the seal using either a ruler, verniers or calipers.

Take multiple measurements around the seal when measuring diameters, in order to apply an average measurement.

3. Measuring multi part seals

Measure the OD, ID and width of the seal.

4. Measuring Bearing Rings

When measuring Bearing Rings, take measurements including the gap.

5. Measuring O-Rings

For O-Rings, measure the section using either a ruler, calipers or verniers.

Always measure an O-Ring from it's internal sides.

Alternatively, you can measure an O-Ring using a measuring cone.

All measurements can be cross-referenced with an O-Ring chart. Contact us to order one

6. Ordering replacement seals

Having the correct measurements can make ordering replacement seals easier.

If you are still unsure, our knowledgeable team are always on hand to help you out.


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