Belts, Gears, and Pinions
In most industrial organizations, installation, adjustment, inspection, and care of belts is the responsibility of a specially trained individual or group. The application of belts involves alignment and belt tension, which affect bearing operation. Maintenance personnel must report belt alignments
that seem inaccurate, tensions that appear excessive, and splices that look doubtful. Drives having upward belt tension may be questioned. Bearing loads on sleeve-bearing motors should not be against that portion of the bearing where the oil is fed into the bearing. Action should be taken to pro- tect the electrical apparatus when there is evidence of belt-produced static.
Gears and Pinions
Gears and gear trains are among the principal sources of noise and vibration. In designing such mechanisms, the manufacturer strives for the best tooth term to give the least amount of whip and backlash, with the gear center so located that the teeth mesh at the correct pressure points.
It is essential, therefore, that the bearings be so maintained that these gear center distances do not change. Correct lubrication of gears is essential to keep down the wear of teeth. A gear with worn teeth, even though it appears to have considerable life left in it, should be replaced to keep vibration and noise to a minimum.