Why are there different Sheave Gauges formats?

In order to ensure optimal performance of sheaves and wire rope a complete range of sheave gauges should be used. We stock gauges in the following formats:

+2.5% API Sheave Gauges are used to determine when Maximum and Excessive Wear levels has been reached.

+5% Sheave Gauges are legacy format. They should fit snugly in new or re-machined sheaves. If correctly sized wire rope is run through the sheaves there will be a minimum of friction which should extend the life of the wire rope.

+6% API Sheave Gauges measures the minimum size for a new sheave.

+10% API Sheave Gauges measures the maximum size for a new sheave.

Other formats can be custom made upon request.