Installation, Operation and Maintenance Manual
CD, HL & NC Ranges of Dri-Prime
®
Pumps
8
95-0019-0000 Iss 11
Pump
Driver
Parallel alignment.wmf
Pump
Driver
Angular alignment.wmf
6.2 Alignment
The following notes provide general guidance on alignment and its elimination.
It is normal practice to carry out any adjustment to alignment by moving the driver – not the pump. In designing any
structure to support the pump set allow an additional 0.25mm (0.010”) extra height difference between pump and driver
support for shimming purposes.
There are two forms of misalignment – parallel and angular. Both must be less than the coupling manufacturers’ guidelines
in order for the coupling and bearings to give long and trouble free operation.
It is essential that the baseplate or support structure be fully tightened down before commencing any alignment procedures.
This will ensure that no misalignment is introduced by support structure deformation.
Alignment must always be carried out before any pipework is attached to the pump. Keep a note of the actual figures. Carry
out a check after the pipework has been attached and compare the figures. Any discrepancy must have been introduced by
the pipework attachment and must be corrected by refitting the pipework before putting the pump into service.
CAUTION.
Incorrect coupling alignment will lead to premature bearing and /or coupling failure.
6.2.1 Alignment
Procedure
Roughly align the pump and driver by eye.
a) Parallel
alignment
Mount a dial gauge on the driver shaft with the gauge running on the outer-machined
diameter of the pump coupling (see Figure 6). If the driver shaft is not accessible then the dial
gauge can be mounted on the driver coupling.
Turn the driver shaft, note the total indicator reading, and adjust the driver position
accordingly. Recheck.
Figure 6 Initial parallel alignment check
b) Angular
alignment
Mount the dial gauge on the driver shaft or coupling (as for step a)) and adjust the dial
gauge to run on a mating face of the coupling as close to the outer diameter as
possible (see Figure 7).
Turn the driver shaft, note the total indicator reading, and adjust the driver in the
direction required. Recheck.
Figure 7 Angular alignment check
c)
Confirming parallel alignment
Mount a dial gauge on the pump shaft with the gauge running on the outer-machined
diameter of the driver coupling (see Figure 8). If the pump shaft is not accessible then
the dial gauge can be mounted on the pump coupling provided the mounting face is
concentric with the shaft.
Turn the pump shaft and note the total indicator reading. Adjust the driver in the
direction required and recheck.
Figure 8 Secondary parallel alignment check
After alignment the pump and driver should be fully tightened down and the alignment rechecked to ensure that nothing has
moved in the tightening down procedure.
If a dial gauge is not available, then vernier callipers (or a taper gauge) and a straight edge can be used, providing the
coupling is of a type that permits it.
Measure the gap between coupling faces with the vernier callipers (or taper gauge) at four points equidistant around the
circumference of the coupling. Adjust until all are equal.
Use a straight edge across both machined outer diameters of the coupling at four points equidistant around the
circumference to confirm parallel alignment.
Pump
Driver
Parallel alignment 1 .wmf
