Curtis Dyna-Fog TWISTER XL 3 3950, Instructions Manual For Installation, Operation And Maintenance

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DEFLECTION
BELT SPAN
BELT TENSION
Belt tension is highly important. When in operation both tight and slack strands of
the belt should be in a straight line from sheave to sheave; a very small sag or bow
could be acceptable at the slack strand. Check belt tension after eight (8) hours
operation, followed by periodic inspections to be sure belt is under sufficient
tension and that belt is not slipping or
jumping from the groove.
Proper Tension is found when a force of
one pound is applied to the center of the
belt span, and a deflection between .18
(minimum) and .25 (maximum) inches is
present. The maximum value is indicated
for “New Belt” and new belt should be
tensioned at this value to allow for
expected tension loss. Used belts should
be maintained at the minimum value of
deflection. For reference please see right
diagram.
An excessive belt tension could produce non desirable effects, as shorter life of
bearings (engine and blower), power reduction, higher temperature, etc.
Do not install a new belt on worn sheaves. Such sheaves should be replaced to
insure a proper fit of the belt in the grooves and prevent slippage and premature
belt wear.
If sheave(s) change is required, they are sold already assembled with the shaft (for
the blower) or on the shaft adapter (for the engine). Under normal conditions, the
sheaves will last hundreds of hours before a change could be required.
Do not force belt over sheave grooves. Slack off drive for easy mounting of belt.
Adjust drive and check that belt operates free and clear of all obstructions.
Keep belt clean. Do not use belt dressing. If belt slips, clean and readjust belt
tension.
Keep extra belts stored in a cool, dark and dry place.
CAUTION
Because of the possible danger to person(s) with accidents which may result
in the use of this belt transmission, is important to install the belt guard
before to run the engine. Do not use the machine if the belt guard is not
installed.