Gorman-Rupp Pumps 04C3-B 407671 and up - Manual (Page 14)

OM-01218 0 SERIES
PAGE B - 6 INSTALLATION
every 90
_. The coupling is in alignment when the
hubs are the same distance apart at all points (see
Figure 4).
Check parallel adjustment by laying a straightedge
across both coupling rims at the top, bottom, and
side. When the straightedge rests evenly on both
halves of the coupling, the coupling is in horizontal
parallel alignment. If the coupling is misaligned,
use a feeler gauge between the coupling and the
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.