Xylem G&L A-C 9100 Series, Instruction Manual

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4.2.3 Align the pump using a dial indicator
• Make sure that each hub is secured to its respective shaft and that all connecting
and/or spacing elements are removed at this time.
• The gap between the coupling hubs is set by the manufacturer before the units are
shipped. However, this dimension should be checked. Refer to the coupling
manufacturer’s specifications supplied with the unit.
1. Check the angular misalignment:
a) Mount the dial indicator base to one coupling half, or shaft.
b) Position the dial indicator button on the front face or rear face of the opposite
coupling half.
c) Mark the index lines on the coupling halves as the following Figure shows:
P
A
R
1
1
2
3
A Angular alignment
P Parallel alignment
1 Dial indicators
2 Index line
3 Resilient separator
Figure 7: Pump alignment via dial indicator
d) Set the dial to zero.
e) Rotate both coupling halves together and make sure that the index lines remain
matched.
f) Reposition the equipment until the offset is within the permissible value.
2. Check the parallel misalignment:
a) Mount the dial indicator base to one coupling half, or shaft.
b) Position the dial indicator button on the outside diameter of the opposite coupling
half.
c) Set the dial to zero.
d) Rotate both coupling halves together and make sure that the index lines remain
matched.
e) Reposition the equipment until the offset is within the permissible value.
f) Assemble coupling. Tighten all bolts and set screw(s). It may be necessary to repeat
steps for a final check.
For single element couplings, a satisfactory parallel misalignment is .004” T.I.R., while a
satisfactory angular misalignment is .004” T.I.R. per inch of radius R.
4 Installation
18 G&L Pumps Series A-C 9100 Base Mounted Centrifugal Pumps INSTRUCTION MANUAL