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V-Belts

In the drilling system, V-belt drives are primarily used for
the mud pumps; however, smaller where a softer, more flexible
connection is desired than would be obtained with chain. V-belts
are generally considered for fairly long drives installations are
used for a multitude of auxiliary drives such as generators,
washdown pumps, oil pumps, etc. Among their advantages are
lack of required maintenance, shock and vibration absorption, and
their overall rugged and dependable action.
Due to the light weight of the belts and the light open guard
commonly used, V-belts are often used on portable packages
because of the weight factor as well as their other advantages.
V-belts are driven by the action of the sheave grooves upon
the sides of the belt. In fact, the belts are always selected to fit the
sheaves so that they do not bottom in the grooves and touch the
sheave root diameter. Belts are usually ordered, stored and in-
stalled in matched sets so that all the belts will be of equal enough
length to allow the load to be equally divided among them.
As a result of the important usage of V-belts in the oil fields,
the API has developed considerable valuable data concerning their
selection, application and use. This information is published in
API Standard 1, and the following information on installation,
maintenance and operating practices is reproduced with the
permission of the API:
Installation. Proper attention should be given to the
following items during the installation of V-belts:
a. Sheaves should be aligned and shafts should be parallel
and free to rotate.
b. V-belts should never be run on or forced over sheaves.
Centers should be slacked off until belts can be placed in the
grooves by hand. Before initially tightening any set of belts, care
should be taken to trace the slack in each belt to the same side of
the drive. Tightening the drive before this is done can result in

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