Manual Chapter 5

8-5
Alignment Application Notes
Proper Foundation
On new installations, allow foundation concrete to cure sufficiently before
installing your machines. Normally, you should not mount machines
directly on the foundation. Base plates usually provide more stability. Also,
to make future alignments easier, a set of high quality (stainless steel, etc.)
pre-cut shims should be placed beneath each foot. These should be at least
1/8 inch (3 mm) thick.
Coupling Considerations
CSI’s alignment system is not affected by axial float and the effects from
torsional play (backlash) in the coupling are minimal. However, you should
ensure that the coupling is properly installed and not in such poor condition
that it adversely affects the alignment process. Also, CSI recommends
(while alignment is being performed) that you eliminate torsional play by
rotating the driving machine in the same direction that it normally operates.
If necessary, put a drag on the driven end to prevent gravity overswing.
Minimize Pipe Strain
Excessive pipe strain can create serious problems and should be corrected
before attempting machine alignment. Ensure that pipes are fitted correctly
and, if necessary, have some flexibility. In some cases, stationary pipes
fitted directly to the machine can cause machine movement as they heat up
(thermal growth).
Changes That Occur During Operation
Machine alignment can change significantly as machines are started from a
“cold” position and run up to operating speed (“hot” position). Some factors
that can influence alignment include:
• Thermal growth
• Torque transmission forces
• Aerodynamic forces
• Hydraulic forces
Chapter 8 Page 5 Friday, January 26, 2001 10:34 AM