Learn how to measure the rotating seal head, shaft or sleeve, spring, and stationary mating ring so the dimensions can be used for identification or replacement.
Accurate dimensions are one of the most useful ways to identify or cross-reference an unknown mechanical seal. This guide walks you through each measurement, explains what it means, and shows where to place your calipers. You do not need to know the manufacturer or part number to use this guide.
Ideally, have digital or dial calipers, the removed mechanical seal, the rotating seal head, the stationary mating ring, and a clean work surface. You can still continue if you are missing some of these items. Enter what you can measure and select "I'm not sure" for anything you cannot.
This determines which operating height formula applies. If you are not sure, select "Not Sure" and skip the operating height calculation.
The measurements you enter here can be added to your quote request. You can measure multiple seals before submitting.
This is the outside diameter of the shaft or sleeve where the seal fits. Measure with calipers for accuracy. Do not measure over threads, keyways, or worn areas.
This is the inside diameter of the seal head or bellows where it fits over the shaft or sleeve. Some elastomer bellows designs may have compression or squeeze that affects the measured dimension. Measure the inside diameter as carefully as possible and record the raw value.
This is the outside diameter of the rotating seal head. Measure the widest part of the head assembly.
Measure the total length of the rotating assembly in its relaxed, uncompressed state. Do not include the stationary mating ring in this measurement.
Measure the outside diameter of the stationary mating ring.
Measure the inside diameter (bore) of the stationary mating ring.
Measure the axial thickness (width) of the stationary mating ring. For cup mounted designs, the elastomer cup may be part of the measured assembly depending on the identification method. Record what you measure and note any observations.
When you continue to request a quote, your measurements and guide details will go with you.
Add these measurements to your quote request. You can add another seal afterward or continue to submit your request.
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