Gorman-Rupp Pumps 06B20-B 806819 and up - Manual (Page 13)

OM-01221 0 SERIES
PAGE B - 6 INSTALLATION
straightedge to measure the amount of misalign­
ment.
Drive Belts
When using drive belts, the power source and the
pump must be parallel. Use a straightedge along
the sides of the pulleys to ensure that the pulleys
are properly aligned (see Figure 5). In drive sys­
tems using two or more belts, make certain that the
belts are a matched set; unmatched sets will cause
accelerated belt wear.
MISALIGNED:
SHAFTS
NOT PARALLEL
MISALIGNED:
SHAFTS
NOT IN LINE
ALIGNED: SHAFTS
PARALLEL AND
SHEAVES IN LINE
Figure 5. Alignment of V‐Belt Driven Pumps
Tighten the belts in accordance with the belt manu­
facturer's instructions. If the belts are too loose,
they will slip; if the belts are too tight, there will be
excessive power loss and possible bearing failure.
Select pulleys that will match the proper speed ra­
tio; overspeeding the pump may damage both
pump and power source.
Do not operate the pump without the
guard in place over the rotating parts
.
exposed rotating parts can catch cloth­
ing, fingers, or tools, causing severe in­
jury to personnel.
DRIVE BELT TENSIONING
General Rules of Tensioning
For new drive belts, check the tension after 5, 20
and 50 hours of operation and re‐tension as re­
quired (see the following procedure for measuring
belt tension). Thereafter, check and re‐tension if re­
quired monthly or at 500 hour intervals, whichever
comes first.
Ideal drive belt tension is the lowest tension at
which the belt will not slip under peak load condi­
tions. Do not over‐tension drive belts. Over‐ten­
sioning will shorten both drive belt and bearing life.
Under‐tensioning will cause belt slippage. Always
keep belts free from dirt, grease, oil and other for­
eign material which may cause slippage.