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
ALIGNMENT BASICS
The machines we align:
Basic
The most basic machines to align consist of a driver and driven element.
The driven unit is usually considered to be stationary and the driver movable.
The movable unit is repositioned in relation to the stationary unit.
Machine Trains
Sometimes a machine train will include a driver, and more than one driven
element. When aligning a machine train, there is more than one alignment
to be made.
Typical Drivers: Electric Motor, Steam Turbine, Gas Turbine, Engine, Wind
Turbine, Hydraulic Motor
Typical Driven Elements: Pump, Fan, Generator
Intermediate Devices: Gearbox, Clutch, Fluid Coupling
Rotational axes
All shafts, straight or bent, rotate on an axis which forms a straight line.
Shaft Alignment Defined
Shaft alignment is the act of measuring the relative position of two machines
that are coupled and repositioning them so that the rotational axes of the
two shafts form a straight line (collinear) when the machines are at normal
operating temperatures.
Types of Misalignment
Offset Misalignment
Offset Misalignment is the actual radial position of the movable rotational
center relative to the stationary center. If the shafts are not parallel, the
offset misalignment is different at every axial position.
Offset misalignment is expressed in mils.
ƒ
0.001" = 1 mil
Offset Misalignment VS Dial Readings
If a dial indicator measuring on the rim is set to zero and then rotated 180
degrees the dial reading (TIR) will be 2X the offset misalignment.
ƒ
Offset misalignment = ½ TIR
Angular Misalignment
Angular Misalignment is the slope relationship of the two shafts. The slope
has a positive value if the offset values are more positive at the rear feet than
at the coupling.
Angular misalignment is expressed in mils per inch.
Stationary Movable
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