Upblast Centrifugal Roof Exhaust
9
Tapered Bushing Hub Installation
and Removal
For wheel hubs and shaft pulleys utilizing a tapered
bushing interface, follow this procedure for installation
and removal. There are two possible set ups for the
tapered bushing, both have the same procedure, but
orientation of the hub varies.
Tapered Bushing Removal:
1. If present, loosen the setscrew holding the bushing
and shaft key in place.
2. Loosen and remove the socket head cap screws
which fasten the bushing to the hub as shown in the
section views and examples of Figures 18-21.
3.
Standard Mounting:
Take the two socket head cap
screws that were removed and install them into the
visibly threaded holes on the wheel hub.
Reverse Mounting:
Install the two socket head cap
screws into the visibly threaded holes of the bushing
flange.
4. Once both socket head cap screws are installed,
tighten them an eighth of a turn at a time, alternating
between the two until the hub comes loose from the
bushing.
Standard Mounting
Reverse Mounting
Figure 18
Figure 19
Figure 20
Standard Bushing Orientation
Figure 21
Reverse Bushing Orientation
Bushing
Washers
Cap Screws
Hub
Bushing
Washers
Cap Screws
Hub
Bushing Installation
1. Clean all surfaces of hub and bushing to remove any
oil or residue present and do not use any lubricant to
install bushing into the hub. For both standard and
reverse mounting styles, the socket head cap screws
are adjustable from the inlet of the fan.
2.
Standard Mounting:
Slide the bushing and shaft
key onto the fan shaft followed by the wheel and hub
assembly. If present, use the keyway setscrew to
hold the shaft key and bushing in place but DO NOT
overtighten as this can damage the bushing. Align
the unthreaded holes of the hub with the threaded
holes of the tapered bushing.
Reverse Mounting:
Slide the wheel and hub
assembly onto the fan shaft followed by the bushing
and shaft key. If present, use the keyway setscrew to
hold the shaft key and bushing in place but DO NOT
overtighten as this can damage the bushing. Align
the unthreaded holes of the tapered bushing with the
threaded holes of the hub.
Installation and maintenance are to be performed only
by qualified personnel who are familiar with local codes
and regulations and who are experienced with this type
of equipment.
Motor maintenance is generally limited to cleaning
and lubrication (where applicable). Cleaning should be
limited to exterior surfaces only. Removing dust buildup
on motor housing ensures proper motor cooling.
Greasing of motors is only intended when fittings are
provided. Many fractional horsepower motors are
permanently lubricated and should not be lubricated
after installation. Motors supplied with grease fittings
should be greased in accordance with manufacturer’s
recommendations. Where motor temperatures do not
exceed 104ºF
(40ºC)
, the grease should be replaced
after 2,000 hours of running time as a general rule.
Wheels require very little attention when moving clean
air. Occasionally, oil and dust may accumulate causing
imbalance. When this occurs, the wheel and housing
should be cleaned to ensure smooth and safe operation.
All fasteners should be checked for tightness each time
maintenance checks are performed prior to restarting
unit.
• When installing fans for restaurant exhaust
applications follow NFPA 96 for cleaning fans.
• Grease containers must be emptied at regular
intervals to prevent overflow.
A proper maintenance program will help these units
deliver years of dependable service.
IMPORTANT
Uneven cleaning of the wheel will produce an out of
balance condition that will cause vibration in the fan.
