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MVA 02 rev 5 - December 2017
Check drive belt tension at least after about the first 8 hours of operation, and then follow the indications
given for programmed maintenance (see paragraph 12.3).
Completely replace belts when worn to a degree that affects satisfactory operation of the transmission due to
an insufficient value of pre-tension or if slipping is more than 4-5%. Belt wear depends on various factors,
including environmental factors, the number of operation hours, and the number and type of start-ups.
The manufacturers of standard V-belts recommend that an ambient temperature of 80°C
should not be exceeded. For higher temperatures, special belts are necessary.
Dirty belts must not be cleaned with solvents like petrol, benzene, turpentine, etc, or with abrasive or sharp
instruments.
It is advisable to use a solution of alcohol and glycerine in a proportion of 1:10. The transmissions installed
on
FVI
fans have two or more drive belts.
In the case of breakage of one or more belts, it is advisable to replace the entire set.
8.5
Flexible couplings
According to fan operating conditions, periodic checks should be made on axial play S, angular alignment
A
max
-A
min
and parallel alignment R (Fig. 8-4, Fig. 8-5, Fig. 8-6). Check the condition of hubs, and lubricate
every 3000 hours of operation using the lubricants and quantities recommended (see Chart 8-6).
Fig. 8-4 Axial play
Fig. 8-5 Angular misalignment
Fig. 8-6 Parallel
misalignment
S
R
A
min
A
max
