Page 344 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

324 Major Process Equipment Maintenance and Repair

B.

Figure 7-12. Belt installation procedures-(a) bad, vs. (b) good.

Tensioning V-Belt Drives

Without exception, the most important factor in the successful opera-
tion of a V-belt drive is proper belt-tensioning. To achieve the long, trou-
ble-free service associated with V-belt drives, belt tension must be suffi-
cient to overcome slipping under maximum peak load. This could be
either at the start or during the work cycle. The amount of peak load will
vary depending upon the character of the drive machine or drive system.
To increase total tension, merely increase the center distance. Before at-
tempting to tension any drive it is imperative that the sheaves be properly
installed and aligned. If a V-belt slips it is too loose. Add to the tension by
increasing the center distance. Never apply belt dressing as this will dam-
age the belt and cause early failure.