Aerovent IM-745 - Manual (Page 2)

2 Aerovent IM-745
Never transport the shaft and wheel sub-assembly by
rolling the wheel to its desired location, as this will dam-
age the gel coat and can affect the wheel balance. Do
not support the shaft and shaft sub-assembly on the fan
housing sides.
Bent shafting is a source of vibration and bearing
failure, so handle the shaft with care. Any scratches on
the shaft may be removed with a fine grit emery cloth,
crocus cloth, or whetstone.
SHORT TERM STORAGE
If fan installation is to be delayed, store the unit in an
environmentally stable and protected area. During storage,
the fan should not be subjected to vibration or shock
loading from external sources, as bearing damage may
occur. The unit should be reasonably protected from any
impacts. Cover the fan to prevent any foreign material or
moisture from entering the fan inlet or discharge. Protect
the fan bearings, drives, and motor bearings from moisture.
LONG TERM STORAGE
Extended storage requires monthly inspections to be
performed and documented.
Fan bearings tend to take on moisture if the atmo-
sphere they are stored in is not at a constant temperature.
To avoid corrosion, it is necessary to keep the bearings
full of grease and to rotate the fan shaft periodically. Even
when full of grease, bearings will take on moisture, so it
is necessary to purge the bearings with new grease to
expel moisture every thirty days. It is recommended that
when the bearing are being greased, that the fan shaft is
rotated by hand. Do not use high pressure greasers as
they may ruin the bearing seals.
The drive and belt should be removed if the fan is to
be stored for a prolonged period of time. Exposed
machined surfaces on the sheaves, fan shaft, and motor
shaft are to be suitably protected against rust. The drives
should be labeled for service and stored in a dry place.
Belts should be coiled without kinks, placed in a heavy
carton, and stored in a dry, well ventilated place. Storage
conditions should not exceed 85°F (29°C) and 70% humid-
ity to prevent belt deterioration.
If the unit was supplied with a motor, the motor should
be stored in a clean, dry, vibration-free location. The motor
windings resistance should be measured at this time and
recorded for comparison prior to placing into service. The
winding temperature should be kept slightly above that of
the surroundings to prevent condensation from occurring.
This can be accomplished by energizing the motor’s inter-
nal heaters, if it is so equipped, or by using space heaters.
If it is impossible to heat the windings, the motor should
be wrapped tightly with a waterproof material which also
encloses several bags of desiccant. Replace the desiccant
regularly to prevent moisture problems. The motor rotor
should also be rotated monthly to assure the bearings are
well covered in grease.
If the fan housing was supplied with a drain connection,
this plug should be removed to prevent any moisture from
accumulating in this portion of the unit during storage.
Fan Storage Procedure – Fans should be stored indoors
whenever possible in an area where control over tempera-
ture, moisture, shock, and dust is reasonably maintained.
If units are to be stored outside exposed to the elements,
they should be covered with a water-resistant material.
Stored equipment should be stored on a clean, dry floor
or blocked up off the ground on blocks to prevent unit
from setting in any water. The floor or blocks upon which
the fans rest upon must be stable and capable of provid-
ing continuous support to the fan structure which will
prevent uneven loading of the fan structure. The fan bear-
ings should be shielded individually from water and dirt;
however, do not tightly seal the bearings to avoid trapping
condensation. If shock or vibration will be present during
the storage period, the unit may need to be placed on
some type of vibration dampening material to aid in pre-
venting brinelling of the bearing surfaces.
Periodic Check – On a monthly interval, the equipment
should be checked to ensure that it has remained in an
acceptable stored condition. Make sure there is no corro-
sion, no damage to the unit, and that there is no debris
within the fan housing.
The fan (and motor, if supplied) should be rotated sev-
eral times by hand while adding enough grease to replen-
ish the bearing surfaces with fresh grease and to maintain
a full bearing cavity. Grease used must be compatible with
that already supplied in the motor and fan bearings. The
fan impeller should be left at approximately 180° from that
of the previous month to prevent the shaft and impeller
from taking a set in one position.
Consult the motor manufacturer for proper storage,
space heater connection, and lubrication, if applicable.
Storage records should be maintained which indicate the
above requirements have been followed.
Prior to Start-Up – When the unit is removed from stor-
age, all grease in the fan bearings should be purged and
replenished with fresh grease as per the lubrication decal.
Spherical roller bearings split pillow block housings should
be recharged with grease. The bottom half of the housing
should be 1/3 full.
The motor winding resistance should be measured to
verify that it is still at a satisfactory level compared to the
value recorded prior to storage. Motor is to be installed
on the fan per original location. Motor shaft and fan shaft
to be cleaned to bare metal.
Drives are to be cleaned to bare metal, installed, and
aligned per manufacturer’s recommendations.
If belts show signs of deterioration, they should be
replaced prior to start-up. Belts are to be installed and
tensioned per manufacturer’s recommendations.
Replace the fan housing drain plug, if applicable.
FOUNDATION and SUPPORTING
STRUCTURES
The preferred means of floor mounting a fan is on a
well-designed, flat, level concrete foundation. The foundation
should have a mass of at least three to five times that of
the supported assembly. The foundation should extend at
least 6” beyond the outer dimensions of the fan and driver;
however, it should be no more than twice the area required
for the equipment. If it is made larger, the mass should be
increased accordingly to resist rocking modes of vibration.
“J”, “L”, or “T” type anchor bolts of sufficient size should
be used and should be tied into the foundation reinforcing
bar. After the concrete is poured, a pipe sleeve with a
diameter of 2 to 2-1/2 times the anchor bolt diameter
should be provided around each anchor bolt to facilitate
final adjustment (see Figure 8). The mounting surface of the
foundation should be smooth for good shim contact. When
deciding the thickness of the foundation, approximately 1"
to 1-1/2" in height should be allowed for shimming, grouting,
and leveling nuts.
If a structural steel base or platform is to be used for
fan mounting, the support structure must be designed for
the weight of the fan, the live loads imposed by rotation of
the rotor and driver, and any external live loads. The struc-
ture should be designed to ensure that no natural fre-
quency will be present within 30% of the fan speed and