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nuaire.co.uk
029 2085 8400
21. 10. 19. Leaflet Number 671798
Installation and Maintenance
AXUS Circular Short Cased Axial Flow Fans
3. Disconnect the conduit at the end of the case (if provided); attach a suitable
lifting strap to the motor lifting point using appropriate D shackles. Attach a
lifting system of sufficient capacity to a lifting strap and remove any slack in
the strap. Loosen the pad to motor fixings, gently raise the motor.
4. Remove all motor fixings (either side of the motor) as per Figure 8, ease the
motor clear of the fan casing then lower onto a suitable pallet for removal.
5. Motor installation is the reverse of removal.
6. If using stainless steel cap head screws, Loctite 290 thread locker should be
applied to each screw prior to fitting (provided by others).
7. The cap head screws must be tightened as per manufacturer’s
recommendations shown in table 1.
8. Centralise the motor within the casing, the tip clearance must be set
evenly around the whole of the case; this is extremely important due to the
expansion rates of the materials involved.
9. Wire the replacement motor to the termination enclosure. Conduct all
electrical safety checks.
Refit the impeller retaining bolt and washer, having first applied Loctite
290 thread locker to the thread (provided by others). Whilst ensuring
that the thread locker does not run into the hub/shaft joint.
10. The retaining bolt can then be re-torqued to the manufacturer’s
recommended torque setting shown in table 3.
11. Ensure that the impeller turns freely by hand. Check the impeller
centralisation by measuring the tip to casing clearance.
12. M8 fixings must be torque tightened to 24Nm and all M10 fixings to 49Nm.
6.0 MAINTENANCE
It is the responsibility of the System Designer and Plant Operator to determine
an appropriate inspection routine for industrial products.
It is suggested than an inspection interval for the wide range of application
types encountered for this type of product may be determined by the following
procedure :-
•
Initial inspection after one week of operation.
•
Secondary inspection after one month of operation.
•
Subsequent inspection interval between one month and six months
depending on the degree of contamination and/or operational stress
encountered.
The inspection shall consist of observation of the fan operation (through a
representative operational cycle) to establish if adverse vibration exists.
Vibration limits should be defined by the system designer with regards to the
specific application design. As guidance the manufacturer recommends that on
start-up, velocity limits of no greater than 5mm/s RMS are accepted.
Alarm limits are recommended for no greater than 8mm/s RMS where
inspection and/or shut down must occur.
With the fan isolated, an examination of all unit fixings, services connections
and structural components shall be made. In addition, operational clearances
between moving and stationary parts shall be checked. The tip if the impeller to
case minimum dimension is outlined in table 2.
Any superficial build-up of contaminants should be removed as necessary to
facilitate inspection, and any defects noted and assessed.
The unit must not be operated if any structural or rotating parts are found to be
in a defective condition.
The unit must be maintained in a clean condition by using soft cleaning tools
and water as required.
7.0 REPLACING THE MOTOR
This replacement of motor section refers to Nuaire's IE3 pad mounted motor
range. For guidance on IE2 refer to document 671850, for other motor variants,
contact the manufacturer for details. Specific values may be different.
Thoroughly examine the goods upon receipt and immediately report any
damages or deviations to the seller, supplier or agent quoting the order and
product details from the rating plate.
Ensure that the installation is isolated in a safe manner and cannot be re-
energised by any other party when the installation is being worked on. Also
ensuring all other connecting components of the system are isolated in the same
manner i.e. other fans, dampers etc.
Where eye-bolts are provided with the motor, these are designed to support
the weight of the motor only, and should not be used to support the weight of
the motor and any ancillary equipment attached to the unit. Be absolutely sure
that cranes, jacks, slings and lifting beams are capable of carrying the weight of
equipment to be lifted.
If suitable lifting equipment cannot be used within the installation, remove
the unit from the installation to a safe working area, placing the unit in the
horizontal plane and chock securely.
1. Using suitable gloves and an appropriate socket, remove the impeller
retaining bolt as per Figure 7. Ensure that the impeller is restrained by hand
when attempting to undo the bolt.
2. The impeller is free to be slid from the motor shaft. This must be done by
supporting the impeller until it is completely free from the motor shaft,
allowing the full weight of the impeller to bear on a short length of the bore
may cause distortion or create a burr that will bind the impeller and prevent
total removal. Disconnect the electrical supply from the terminal box to the
motor.
Pad to Motor
Motor Frame Size
Torque Setting (Nm)
80
8
90
16
100
16
112
20
132
40
160
45
Table 1: Torque settings for pad to motor cap head bolts.
Figure 7. Removal of retaining bolt.
Figure 8. Removal all motor fixings.
