Belts & power transmission
V-Belt Replacement Size Guide
Do not buy a V-belt from one circumference measurement alone. Preserve the belt marking when possible, identify the section and length convention, and verify the sheaves and duty before choosing a replacement.
Photograph and transcribe every readable letter and number before the old belt is discarded.
Record top width, height, rib or band configuration, and whether the drive uses a classical, narrow, cogged, joined, or specialty construction.
Use the manufacturer's measurement method or belt-length tool when possible; outside, inside, pitch, and effective length are not interchangeable labels.
Record groove count, groove condition, pulley diameters, alignment, and whether the sheaves are intended for the same belt profile.
Record center distance, take-up range, tensioner arrangement, and available installation clearance.
Capture motor power, speed, driven equipment, starts, shock load, temperature, oil exposure, and hours of service.
The belt section must match the sheave groove geometry.
Compare like-for-like manufacturer dimensions instead of assuming two similarly stated lengths are equivalent.
Cogged, wrapped, banded, raw-edge, static-conductive, oil-resistant, or specialty belts can have different application limits.
The replacement must be appropriate for the transmitted power, speed, service factor, and number of belts in the set.
Worn sheaves, misalignment, poor tension, or insufficient take-up can make a correct belt appear to be the wrong size.
A worn belt can stretch or sit differently in the groove, and manufacturers may publish a different length convention.
Section, construction, effective length, and application rating can still differ.
A new belt in worn grooves can ride at the wrong depth, reduce grip, and distort tensioning.
Matched-set requirements and belt tolerances matter on drives that share load across multiple belts.
Yes, but use the measurement as one input. Gates publishes a V-belt length finder specifically to measure an old belt and identify a corresponding replacement length.
The section, width, construction, length convention, and drive rating can differ even when the nominal length looks similar.
Not automatically, but inspect them for wear, damage, alignment, and compatibility with the replacement belt profile.