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-- 12.13) TRANSMISSION BELT ---
-- 12.13.1) CHECK OF TRANSMISSION BELT TENSIONING ---
For normal, efficient compressor functioning the transmission belts must always be perfectly
tensioned..
Tensions inferior or superior to those ones we recommend, could cause working anomalies like the sliding or
the premature wear and tear of the belt. The mounting of the belt has to be made without using any
instrument ( for instance levers ) that could incise the belt or the pulley.
These instructions (Fig. 15) must be followed to determine the exact tensioning of the transmission
belts.
To determine the right tension, measure the arrow “f” caused by the application of a force “Q” in the
middle of the free part of the belt. The force has to be perpendicular to the belt.
Arrow
f
must be 1,5% of the free section
“l”
applying a Q force equivalent to 40 ÷ 47 N for RVK 8-10-15 and
of 50 ÷ 63 N for RVK 20.
If the arrow value
“f”
exceeds the indicated value it means that the belts are slack, while if the value is lower
than this it means that the belts are too taut.
Warning:
Belts that are too loose could slip and cause loss of compressor power.
Belts that are too tight deteriorate and consequently break.
Warning:
Check belt tension during the first 50 working hours
Please note that the belts, above all during the first 50 working hours, undergo a slight setting-
in and consequently mild stretching.
In this situation the belts may be subject to slipping and, as a result, overheating which could
cause breakages.
This is why we strongly recommend the user, after no more than 50 working hours, to check
and re-tension the belts. Once this operation has been carried out the belt length is stabilised
and subsequent checks must be done following the instructions in the “Maintenance
Programme” chapter.
For belt tightening see the instructions in the chapter “Tensioning and Replacement of
Transmission Belts”
Fig. 15
