Improve V-Belt Drive Performance

Like cats and dogs, V-belts have a language of their own. The problem is that end users may not understand what their belt is trying to tell them.

Suddenly, something goes wrong. The drive is shut down, and the belt is replaced or retensioned. The belt may not cost much, but the time needed to fix the problem can cost a bundle, especially if the belt is offshore or miles out in the field.

What if the user could speak the belt’s language? It could let the user know how to prevent premature failure, and that could translate into longer belt life, improved drive efficiency, reduced maintenance and downtime and improved productivity.

Isn’t that worth a little lesson in belt talk?

What’s Normal?

Any mechanical component fails eventually. So, what’s normal failure for a V-belt?

The key factors that influence the frequency of belt replacement, regardless of the application, are speed, load and hours of operation. Normal life for some V-belt drives may be three to five years. Others may have a normal service life of less than one year.

When a V-belt fails under normal usage, it is due to fatigue, so the belt eventually pulls apart and breaks. Long before that happens, however, your belt could be speaking to you about any number of problems, all of which can be fixed.

Recognizing Obvious Problems

Obvious symptoms of a problem drive include excessive noise, vibration, and heat; so a preliminary examination involves looking, listening, and touching. A belt that squeals or chirps, makes a slapping, rubbing or grinding sound or even an unusually loud drive is a sign of trouble. Unusual or excessive vibration, a belt that is hot to the touch or a belt flopping in the sheave also signals trouble.

Any sign of unusual belt wear points to a potential problem with the drive. To conduct a thorough inspection, shut down and lock out the drive and examine all components carefully:
• Belt(s)
• Sheaves
• Belt guard
• Bearings
• Shafts

On the belt, look for uneven wear patterns, cracking, frayed covers, burned spots, swelling, and hardening. The following sections will examine what these clues tell end users about the drive.