I.C.E. BMA-136 HBR - Manual (Page 16)

15
TENSIONING V-BELT DRIVES
1. Ideal tension is the lowest tension at which the belt will not slip under peak load conditions.
2. Check tension frequently during the first 24-48 hours of operation.
3. Over-tensioning shortens the belt and bearing life.
4. Keep belts free from foreign material that may cause slip.
5. Make V-drive inspection on a periodic basis. Tension when slipping. Never apply belt dressing as this will damage the
belt and cause early failure.
Check and tighten belt tension. The following procedure is recommended for tightening belts:
a) Measure span “X” shown in Figure A.
b) At the center of span length “X”, apply a force perpendicular to the span and large enough to deflect belt 1/64” for
each inch of span length. Example- the required deflection for a 40” span would be 40/64” or 5/8”.
c) Compare the force applied with the values given in Table III. If force is between the minimum and maximum range
shown, the drive tension should be satisfactory. A force below the minimum value indicates an under tightened belt
and force that exceeds the maximum value indicates an over tightened belt.
TABLE III
BELT CROSS MOTOR PULLEY DEFLECTION FORCE
SECTION PITCH DIAMETER MINIMUM MAXIMUM
(Marked on
Belt)
3.0” - 3.6” 2.62lbs. 3.25lbs.
A 3.8” - 4.8” 3.0lbs. 4.0lbs.
5.0” - 7.0’ 3.25lbs. 5.0lbs.
3.4” - 4.2” 3.0lbs. 5.0lbs.
B 4.4” - 5.6’ 4.0lbs. 5.87lbs.
5.8” - 8.6” 5.25lbs. 7.87lbs.
FIGURE A
FORCE
SPAN LENGTH X
PER INCH OF SPAN
DEFLECTION 1/64"