5
4. FLEXIBLE COUPLING ALIGNMENT
A fl exible coupling should not be used to compensate for
misalignment of the pump and driver shafts. The purpose
of the fl exible coupling is to compensate for temperature
changes and to permit end movement of the shafts without
interference with each other, while transmitting power from
the driver to the pump.
CAUTION! - Remove and lock out power to
driver
.
FACTORY ALIGNMENT
Pump and drivers that are received from the factory
with both machines mounted on a common baseplate,
were accurately aligned before shipment. All baseplates
are fl exible to some extent and, therefore, must not be
relied upon to maintain the factory alignment. Preliminary
alignment is necessary after the complete unit has been
leveled on the foundation and again, after the unit is piped,
and rechecked periodically as outlined in the following
paragraphs.
FIELD ALIGNMENT
The faces of the coupling halves should be spaced far
enough apart so that they cannot strike each other when
the driver rotor is moved toward the pump. The necessary
tools for checking the alignment of a fl exible coupling are a
straight edge and a taper gauge or a set of feeler gauges.
NOTE:
In most cases where extreme
accuracy
is
necessary, a dial indicator may be used to align coupling.
Angular alignment check is made by inserting a taper
gauge or feelers between the coupling faces at 90-degree
intervals around the coupling. The unit will be in angular
alignment when the coupling faces are exactly the same
distance apart at all points. (See Figure 2).
Parallel alignment check is made by placing a straight
edge across both coupling rims at the top, bottom and
at both sides. The unit will be in parallel alignment when
the straight edge rests evenly on the coupling rim at all
positions. Allowance may be necessary for temperature
changes and for coupling halves that are not of the same
outside diameter. Care must be taken to have the straight
edge parallel to the axis of the shafts. Correction for
Angular and Parallel Misalignment is made by adjusting
the shims under the driver. After each change, it is
necessary to recheck the alignment of the coupling halves,
as adjustment in one direction may disturb adjustments
already made in another direction.
The permissible amount of coupling misalignment will vary
with the type of pump and driver, but should be limited to
approximately .002 inches per inch of shaft diameter when
fi nal adjustment is made. When the units are lined up cold,
it is necessary to make allowance for the vertical rise of
the driver caused by heating when in operation. When the
preliminary alignment has been completed the foundation,
bolts should be tightened evenly, but not too fi rmly.
Figure 2
PERFECT
ALIGMENT
PARALLEL
MISALIGNMENT
ANGULAR
MISALIGNMENT
Summary of Contents for Deming 5260 Series
Page 7: ...7 Figure 3 ...
Page 22: ...Notes ...
