Milnor 72044SR2, Mechanical Parts And Service, Page: 35 / 175

Pellerin Milnor Corporation
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Tension of Belts
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This data does not apply to belts where a spring holds the correct belt tension. Manual tension ad-
justment is not necessary for this type of drive.
The correct belt tension is the lowest tension that prevents belt slippage with a full load con-
dition. If the belt is too tight, this can cause damage to the belt, the pulleys, bearings, and
other drive components. If the belt is too loose, this can cause belt slippage. Incorrect belt ten-
sion or belt slippage can cause components to make an unusual noise.
When you install a new belt, use these rules to get the correct belt tension:
• Set the tension of the belt when you replace a motor, bearing housing, pulley, or belt.
• Replace all belts on a pair of pulleys when you replace one of them.
• After adjustment, operate the machine in all of its standard conditions to make sure that the
belt operates correctly. For example, operate a washer-extractor in its full speed range with a
full load of wet goods.
• Adjust the tension when you first install a belt. Do the adjustment again after 24 and 48 hours
of operation. All belts will become longer after a short time. A V-belt will move down in the
grooves of the pulleys. These conditions will cause the tension to decrease.
When you do scheduled maintenance, examine the belts for correct tension. With operation, belts
become longer.
The pulleys must stay aligned when you adjust the belt
tension
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Some tension mechanisms do not have an effect on pulley and shaft requirements. Pulleys will
stay aligned when you adjust them.
Figure 13 is an example of these. Where tension mechanisms
are a pair of threaded rods, you must adjust the nut, on each rod carefully. If not, the pulleys will
not stay aligned. Examples of this type are shown in
Figure 14 .
Drive Assemblies