Seven Steps to Maximum Belt Life

Dusty belt and pinion in factory

Take a few extra minutes to help these components deliver on their promise of long, trouble-free service.

Drive belts often receive less attention than they deserve from plant personnel. And why not? The cost of these consumable items is relatively low compared with other components. Improperly installed and tensioned belts, however, can add to operating costs in a number of areas, including higher energy consumption and increased equipment maintenance. In short, they simply run hotter, wear faster, and, ultimately, fail quicker than belts that are correctly installed and tensioned. Such problems, in turn, put a site’s processes and productivity at risk.

Stan Riddle, technical trainer, VibrAlign Inc., Richmond, VA, says the following seven steps can help your facility achieve the many hours of efficient, trouble-free service its drive belts are designed to deliver. While they may take a few more minutes on the part of plant personnel, they can dramatically increase the life of a site’s belts, sheaves, and bearings.”

—Jane Alexander, Managing Editor

Use the right belt size. Belts come in several widths, sizes, and profiles. Make sure belts and sheave groove(s) match.

Never roll belts on. It’s easy to get in a hurry and roll belts into position without loosening the motor. This unsafe practice, which can easily damage belts and sheaves, induces hard loads on bearings and shafts.

Check sheave groove(s) for wear. Sheave wear is often overlooked since many people think rubber belts could never wear out cast iron or steel sheaves. But they can—and do. A sheave-groove measuring tool is inexpensive and usually available from your local power-transmission supplier.

Assure proper sheave alignment. Laser tools really are best for this task. A laser tool allows the user to correct the horizontal offset misalignment, as well as vertical and horizontal angular misalignment, which are difficult to detect with a straightedge or string.

Assure proper belt tension. Correct belt tension is not an exact science, but is important for long belt life. Too little tension leads to excessive heat and noise and can cause belts to slip and pop, reducing their life. Too much tension causes band breakage and dramatically decreases bearing life as a result of excessive radial loading. Invest in a belt-tension tool and become familiar with how to use it. These tools can also be obtained through your local power-transmission supplier.

Assure proper ventilation. Belts can generate considerable heat in normal operation. Be sure the belt guarding is well ventilated to help dissipate this heat.

Re-check belt tension after break-in. This is another often overlooked, but important, step. As belts match the groove profile of the sheave, stretch slightly, and heat up, often the tension will change. A quick re-check and re-tightening, if needed, can substantially increase belt life. When re-tensioning belts, use your laser tool to ensure that the horizontal angular alignment is maintained. MT