GAS COMPRESSORS / BOOSTERS
GAS & AIR MIXING SYSTEMS
AIR BLOWERS & VACUUM PUMPS
The Utile Engineering Co. Ltd.
Irthlingborough, Northamptonshire, NN9 5UG, ENGLAND
Telephone: + 44 (0) 1933 650216 Facsimile: + 44 (0) 1933 652738 Email: [email protected]
www.utileengineering.com
7
IC182
Fitting Pulleys and Couplings
These should be bored to our standard limits (details supplied upon request) and fitted to the shaft with a screwing motion.
On no account should they be driven on. Tapping of fitments onto the machine shaft with a hammer or mallet, causes
bearing damage. This results in an increase in bearing noise and a significant reduction in bearing life. Attention should be
paid to the guarding of all moving parts.
Drive Alignment
The rotor shaft must always be horizontal. There are three basis modes of misalignment, these are angular, parallel and
axial (shown in fig. 4).
Flexible Coupling
1.
Remove any dirt, oil, etc. from all mating surfaces. Place bush in hub and match
half holes on both shafts.
2.
Place setscrews loosely in threaded holes. Mount assembly in desired position on
shafts.
3.
Tighten setscrews. Place disc/flexible coupling in position, and bring the shafts
together obtaining the manufacturers assembled length for the coupling given in
their instructions.
4.
To check for angular alignment: (see fig. 5)
Rotate the coupling through 90
°
and measure the distance between the faces.
Repeat adjusting the shafts until four identical measurements are obtained.
To check for parallel alignment: (see fig. 5)
Place a straight edge across the coupling. The hubs will be in correct alignment
when the straight edge contacts the 4 points squarely.
Drive Belts
1.
Remove any dirt, oil, etc. from all mating surfaces. Place bush in hub and match
half holes on both shafts.
2.
Mount assembly in desired position on shafts ensuring both shafts are parallel and
in correct alignment, use a straight edge, a correctly aligned drive will contact both
pulleys squarely (see fig. 6).
3.
Fit driving belts. Measure span of belts between
tangent points of the two pulleys. A deflection of
1.5mm is obtained for every 100mm of the
measured span. Compare the deflection force
required with the table. If the force required is
according to the table then the tension is suitable.
Too little force indicates under-tension and visa-
versa.
4.
The belts should be tensioned towards the high side, to allow for the tension drop
after the belts have been run-in. Belt tension should be checked daily in the first
week after installation/renewal.
Warning:
Excessive tension on the pulleys will damage the bearings and lead to a probable shaft rupture.
Belts, which become charged electrostatically, must not be used in hazardous atmospheres.
Belt
Section
Force Required to
deflect belt 1.5mm per
100mm span (kgf)
SPZ
0.5 to 0.8
SPA
1.0 to 1.5
SPB
2.0 to 3.1
SPC
4.1 to 6.1
Parallel Alignment Check
Angular Alignment Check
Fig. 5
Angular Misalignment
Parallel Misalignment
Axial Misalignment
Fig. 4
Correct pulley alignment
Span Distance
Fig. 6
Installation
