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j. If the tension section of a belt is ruptured by installation,
accident or use, the condition is evidenced by a necked down
section, and such a belt should be removed from the drive.
k. Belts should not be allowed to run turned over in the
sheave grooves. The tension section of a turned belt is severely
stressed and therefore subject to rupture or permanent damage.
l. Only matched belts should be used on multiple drives:
New and used belts should not be used in the same drive. Used
belts which are still serviceable should be matched to make full
sets.
m. Belts of different makes should not be mixed in the same
drive.
n. V-belts should be kept in position and properly ventilated
and drained.
o. Guards should be kept in position and properly ventilated
and drained.
p. Provision should be made for applying tensions either by
adjusting the center distance or by the use of idlers. If idlers are
necessary, it is best to use a grooved sheave on the inside of the
slack side of the drive, with a diameter not less than the minimum
recommended for drive sheaves.
q. For pump drives with separate skid mounting, it is
recommended that the pump skid be mounted in a cradle equipped
with screws or turnbuckles to provide ample take-up for center
adjustment. The cradle should be anchored to the substructure base
and arranged to float on a pad of such size and design as to resist
shifting and settling out of alignment.
r. Wide and narrow grooves resulting from poor machining
or uneven wear in service will result in "differential driving" and
reduced belt life. Such sheaves should be regrooved or replaced.
s. Some V-belt drives on slush pumps exhibit strong
vibration of the belts, thus contributing to premature belt failure
particularly on drives employing flat (back-bending) idlers on the
slack side. On many such drives the difficulty has been overcome

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