SB--7--627 Page 4
Protective covers and rust preventatives should be left
in place until just prior to installation.
DRIVE INSTALLATION
Large blowers are generally driven by a coupling. On
the direct connected units, adjustments and lubrication
of couplings to the specifications of the coupling
manufacturer are very important. When mounted
drives are supplied from the factory, proper alignment
has been established before shipment. However,
during shipping, handling and installation, it is likely that
the alignment has been disturbed and final adjustment
must be made before startup. To reduce vibration, the
coupling must be aligned to 0.003”/0.005” for both
parallel and angular alignment.
Overtightening belts leads to heavy
bearing loads and premature failure.
When selecting a V--belt drive, check to be sure the
shaft overhung load limitation is not exceeded. Refer
to FIGURE 4, page 5, for overhung load calculations
and limitations.
Belt drives must be carefully aligned. Motor and blower
pulleys must be parallel to each other and in the same
plane within 1/32 inch. Belt tension should be carefully
adjusted to the belt manufacturer’s recommendation
using a belt tension gauge. Check tension frequently
during the first day of operation.
Exceeding overhung load limitations
leads to unwarrantable premature
bearing failure and shaft breakage.
The location of the sheave on the blower shaft greatly
affects the stress in the shaft. The optimum blower
sheave positioning is as close as possible to the blower
drive cover, not to exceed dimension “C” in Drive Shaft
Illustration, FIGURE 4, page 5.
The calculated shaft moment must not exceed the
maximum allowable moment listed in Maximum Allow-
able Moment Chart, FIGURE 4, page 5.
If the
calculated shaft moment exceeds the maximum
allowable moment:
D
Increase Sheave Diameters to Reduce Belt Pull
D
Use Jackshaft Drive
D
Use Direct Coupled or Gearbox Drive
To calculate shaft moment for a given V--Belt Drive Ar-
rangement:
1.
Use the formula for Calculation of Belt Pull,
FIGURE 4, page 5, to calculate belt pull. Refer
to Arc of Contact Factor Chart, FIGURE 4, page
5.
2.
Insert the calculated belt pull into the formula for
Calculation of Shaft Moment, FIGURE 4, page
5, to arrive at the calculated shaft moment.
PIPING
Inlet and discharge connections on all blowers are
large enough to handle maximum volume with
minimum friction loss. Reducing the pipe diameter on
either inlet or discharge will only create additional line
loss and increase the overall pressure differential,
causing increased power and temperature rise.
Excessive weight of piping and fittings will cause
internal misalignment and premature wear. Never
allow the blower to carry the weight of the pipe. If
possible, a spool or sleeve-type expansion joint should
be installed between the unit and the piping. Where a
flexible connection is not practical, the weight of the
rigid connection must be separately supported, and
provisions must be made for thermal growth.
All system piping must be cleaned internally before
connecting to the blower.
Sutorbilt blowers are shipped dry
from the factory. Do not attempt to
operate the blower before following
proper
lubrication
instructions.
Permanent damage to the gears,
bearings and seals will occur.
