KNOW WHEN IT’S TIME TO REPLACE YOUR ROLLER CHAIN

By Rob Raggard

How do you know for sure that you have consumed all of the useful life out of your chain?
With proper selection, installation, maintenance and lubrication, a system should achieve up to 2-3% elongation before the chain needs to be replaced.

CHAIN WEAR: WHAT IT IS AND HOW TO MEASURE IT

Chain wear or chain pitch elongation (“stretch”) is the increase in measured chain length due to wear or excessive load.

CHAIN WEAR

This is expressed as a percentage (%) increase in length.

Chain wear diagram

Chain Wear Diagram

HOW TO MEASURE CHAIN WEAR

how to measure chain wear

How to Measure Chain Wear

1. Pull the chain slightly until it is taut.
2. Use a vernier caliper to measure the distance of the inside (L1) and the outside (L2) of the rollers at both ends of the measured links.
3. The average of (L1) and (L2) gives you the measured length (L).
(L1) + (L2) / 2 = (L).
4. Calculate the standard length as: Chain Pitch x Number of Links.
5. Chain elongation percentage increase in length is calculated as:  Chain Elongation = Measured Length (L) / Standard Length x 100 (%)

Many manufacturers offer a chain wear scale, similar to the example below.

chain wear scale

Chain Wear Scale

Would you like more information about chain selection, maintenance and replacement? Call your OTP Sales Engineer today and speak with an industry expert who can answer all your questions and keep you moving forward.