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6.7 The V-belts
The V-belt drives are designed for the installed driving power. To force a higher output through an excessive
high tension of the V-belts will result in broken belts, damage to the bearings and causes loss of the total
efficiency. Too low belt tension will cause slipping with the result of a very high temperature of the V-belt and
a premature destruction of it. Temperatures over 70° for a longer period will decrease the working life and the
efficiency of the V-belts. The grooves of the V-belt pulleys must be free of rust, fat and dirt and must not show
any damages. The use of belt wax or similar substances in order to increase the friction coefficient is not
necessary and it damages the V-belts. Soiling due to oil, grease or chemicals have to be avoided.
In order to get perfect power transmission the V-belt drives have to be checked every 3 months.
6.8 V-belt mounting
Reduce the distance between the driving motor and the bearing to release the tension of the V-belt
drive.
Carefully put the V-belt in the grooves of the V-belt pulley by hand and without using the force.
Increase the distance between the driving motor and the bearing to stretch the V-belt as following
described.
Fix the required driving gear guards.
6.9 V-belt tension
The correct V-belt tension is of utmost importance in order to obtain a perfect power transmission and to reach
the usual working life of the V-belt. Too low or to high tension causes frequently a premature breakdown of
the V-belt. Excessive belt tension results in damaged bearings at drives.
Check the tension of the V-belt by pressing the thumb on the belt. The belt has the correct tension If you can
press it in about 10-15 mm at approx. 10 kg. pressure.
Remove the belt guard only when the driving motor is in standstill and the power
supply cable of the machine is disconnected from the power source.
