VibrAlign Fixturlaser Go, Руководство по обучению

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I N T R O D U C T I O N T O A L I G N M E N T
Angular Misalignment VS Gap Difference
If you use calipers, inside micrometers, or a dial indicator to measure face to
face misalignment, the result you get is the gap difference top to bottom or
side to side in mils. Angles cannot be expressed as a distance alone. Divide the
gap difference by the diameter at which you measure the gap to express the
gap difference as angular misalignment.
Gap difference/diameter = angular misalignment
TOLERANCES
Angular Misalignment Offset Misalignment
Mils per inch Mils
.001/1" .001"
RPM Excellent Acceptable Excellent Acceptable
3600 0.3/1" 0.5/1" 1.0 2.0
1800 0.5/1" 0.7/1" 2.0 4.0
1200 0.7/1" 1.0/1" 3.0 6.0
900 1.0/1" 1.5/1" 4.0 8.0
MISALIGNMENT FORCES
Misalignment creates forces at the coupling which are exerted on the shafts.
This results in reduced bearing and seal life.
The force effects of misalignment can be simplified by considering the
misalignment as a simple lever. Misalignment at the coupling creates a
moment of force acting on an effort arm. This will create a first class or second
class lever with either the inboard or outboard bearing acting as a fulcrum.
The length of the motor shaft between its bearings is the resistance arm. The
objective of shaft alignment is to minimize coupling forces by making two
rotational axes form a single line while the machine operates.
About making precise alignments:
Fast and accurate alignment should be simple. In fact, most alignments can be
accomplished in one or two corrective moves.
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It is helpful to understand some alignment basics.
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Pre-alignment steps are mandatory.
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You must know when you are finished.
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Rigid couplings present unique challenges and final alignment must be
near perfect.
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Alignment data can be obtained with the couplings assembled or
disassembled.
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When it is humanly possible, both shafts should be rotated when
obtaining alignment data
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