Bolt Torques; Maintenance - Danfoss VLT FCM Series Manual

Maximum permissible external axial and radial loads in N
Load towards
Frame motor
size Poles
80 2 1375
4 1865
90 2 2060
4 2700
100 2 4265
4 5050
112 2 4265
4 5050
132S 2 5295
4 6325
132M 4 6280
1
All figures are based on Lna bearing life of 20,000 hours.
Lna = adjusted L10 life rating taking account of:-Reliability -Material improvements -Lubrication conditions
2
Max. permissible radial load at end of shaft (horizontal mounting).

Bolt torques

Endshields and lid should be secured with the bolt
sizes and torque's detailed in the table below.
Endshield fixing bolt torques
FCM Type Frame size Bolt diameter
Nm.
305-307 80
311-315 90
322-330 100
340 112
355-375 132
LID screws torque: 2.2 - 2.4 Nm

Maintenance

Routine cleaning of the FC motor
Remove the fan cover and ensure that all air inlet holes
are completely free. Clean any dirt and obstructions
from behind the fan and along the ribs of the frame,
and between the motor and inverter part.
Periodic maintenance of motor part.
a. Remove the inverter part, the fan cover and
the fan which is keyed to the shaft extension.
Loosen and remove bearing cover screws and
endshield bolts/studs.The endshields should
then be eased off their spigots.
b. The rotor can now be carefully withdrawn from
the stator, taking care not to damage the stator
bore and both stator and rotor windings.
c. Having dismantled the motor, maintenance can be
carried out to remove all dirt. For this purpose,
the use of an air line supplying dry compressed
air under comparatively low pressure is best, as
MG.03.H3.02 - VLT is a registered Danfoss trademark
Horizontal shaft
Load away
from motor
2205
2745
3190
3825
4265
5050
4265
5050
7015
8045
8045
Torque
M5 5
M5 5
M6 (taptite) 8-10
M6 (taptite) 8-10
M8 (taptite) 29
VLT
1
- reinforced ball bearings
Vertical shaft
Shaft up
load load load
Up Down
2405 1225 1470
2845 1715 1960
2990 1470 1865
3580 2010 2355
4660 4660 4070
5590 5590 4805
4660 4660 4070
5590 5590 4805
7850 4760 6080
9125 5690 7360
9270 5545 7505
a high velocity air-stream can force dirt into the
spaces between the windings and insulation, etc.
Grease-removing solvents can cause damage
to impregnating varnish or insulation
d. The FC-motor should be re-assembled in the
reverse order from dismantling, remembering
to ease endshields onto bearings and spigots.
DO NOT USE FORCE.
e. Before starting, check that the rotor revolves freely.
Ensure that the electrical connections are correct.
f. Refit any pulley, coupling, sprocket etc. which
has been removed, being particularly careful to
ensure correct alignment with the driven part,
as misalignment will lead to ultimate bearing
trouble and shaft breakage.
g. When replacing screws and bolts, care should be
taken to use only those with the requisite quality and
tensile strength recommended by the manufacturer.
These must also be of identical thread form and
screw/bolt length (see the table above).
®
FCM Series
Shaft down
load
Up Down Max. radial
2160 3190
2600 3925
2600 4120
3140 4515
4070 6035
4805 6965
4070 6035
4805 6965
6525 8925
7405 9860
7310 10200
2
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