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© 2011 Gates Corporation
EZ ALIGN is a registered trademark of Gates Corporation
Vertical angularity should be corrected first. This is done by
shimming the unit that the movable pulley is mounted to. The
next step is to correct horizontal angularity. This is
accomplished by shifting or twisting the position of the unit that
the movable pulley is mounted to. Use lateral jackscrews if
available, otherwise the unit will need to be loosened and re-
positioned. Finally, correct offset by moving the unit that the
movable pulley is mounted to axially or reposition one of the
pulleys on its shaft. Since performing one alignment correction
almost invariably affects the other alignment conditions, this
process may have to be repeated several times.
The sequence in which the misalignment correction is carried
out may vary from one situation to the next.
GATES EZ ALIGN
®
enables all three alignment conditions to be
monitored simultaneously. The accuracy of the alignment is
greatly increased and the process can be completed quickly
and easily.
Incorrect belt tension (as well as pulley misalignment)
adversely affects belt drive reliability and efficiency. After the
Shown Vertical Angularity
After Vertical Angle Correction
Shown Horizontal Angularity
Shown Offset
After Horizontal Angle Correction
After Offset Correction
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© 2011 Gates Corporation
EZ ALIGN is a registered trademark of Gates Corporation
pulleys have been aligned, it is very important to tension the
belts to manufacturer’s recommendations.
Force – Deflection Method of belt tensioning:
1. Measure the belt span length and calculate the desired
deflection distance (1/64” per inch of span length)
2. Using a spring scale, press down on the belt in the
approximate center of the span, and deflect the belt to the
desired level. When the desired deflection distance has
been reached, note the force registered on the spring scale.
3. Adjust belt tension until the force required to achieve the
desired deflection distance is within the belt manufacturer’s
recommended force values for the type of belts being used.
New belts generally require higher tension levels than used
belts because they have not been run in.
It is possible for belt tension adjustments to alter pulley
alignment, and for pulley alignment adjustments to alter belt
tension levels. The
GATES EZ ALIGN
®
tool will help monitor the
pulley alignment condition as belts are adjusted for the correct
tension level.
Measuring belt tension with the Gates Sonic Tension Meter::
The Gates Sonic Tension Meter measurers belt span tension
easily and accurately. Belt tension is measured by plucking the
belt span while holding a sensor close by. Belt tension is
adjusted until the belt span frequency, or measured tension
level is within manufacturer’s recommendations.
