5
Maintenance
FläktGroup
DC_9202GB 20180403_R0
Specifications are subject to alteration without notice
TO REFIT
1. Inspect the seals and replace them if they are defective. Fit the
seals, taper sleeve and bearing onto the shaft. Fit the bottom half
of the bearing block in the appropriate position as marked earlier.
Fit the bolts and nuts, but do not tighten them.
2. Rotate the outer race of the bearing through a few revolutions to
ensure that the rollers are in the correct position. Fit the tab
washer and nut onto the sleeve and tighten the nut by hand,
so that the shaft, sleeve and bearing are firmly in contact with one
another. Lower the shaft with the bearing into the bottom half of the
bearing block.
3. Mark one of the tab washer tabs which is in line with a slot in the
nut. Then tighten the nut so that the slot is displaced five tab
pitches from the marked tab, and then fold one of the washer tabs
into a suitable slot in the nut. See Fig. 10.
4. Pack the bearing block and the spaces between the rollers with
SKF ALFA LUBE LG MT2 or equivalent grease.
5. Fit the top half of the bearing block and bolt it in position.
6. Secure the bearing block to the support arm by tightening the
bolts.
Tab pitches
Fig. 10
GROOVED BALL BEARINGS WITH TAPER SLEEVE
(THE BEARING BLOCK HAS NOT GREASE NIPPLES
The SKF type 62(00) – 2RS1K + H2(00) bearings are maintenance-free
and should not be greased.
The bearing is secured to the shaft by means of a taper sleeve.
See Fig. 11.
TO REMOVE
1. Fold back the tab of the tab washer and back off the nut a few turns.
2. Apply a light blow to tap the taper sleeve out of the bearing. Use a
hammer and a drift.
3. Remove the bearing unit from the shaft.
TO REFIT
1. Fit the bearing, taper sleeve, tab washer and nut assembly onto the
shaft. Fit the tab washer so that the tabs slope outwards, and fit the
nut with the chamfered side towards the bearing.
2. Fit the bearing assembly onto the shaft.
3. Tighten the nut by hand, so that the shaft, bearing and taper sleeve
are firmly in contact with one another.
4. Mark one of the tab washer tabs which is in line with a slot in the nut.
Then tighten the nut so that the slot is displaced by the number of tab
pitches (from the marked tab) specified in the table below, and then
fold one of the washer tabs into a suitable slot in the nut.
3634 30;3 EUMM
Fig. 11
Bearing type
Number of tab
pitches
SKF 6205–2RS1K
1,5
SKF 6206–2RS1K
1,5
SKF 6207–2RS1K
1,5
SKF 6208–2RS1K
2
SKF 6209–2RS1K
2,5
SKF 6210–2RS1K
3
TYPE Y BEARING WITH ECCENTRIC LOCK RING (THE
BEARING BLOCKS HAVE NO GREASE NIPPLES)
SKF type YET bearings are maintenance-free and must not be
relubricated. The bearing is secured to the shaft by means of an eccentric
lock ring as shown in figure 12. The bearing is glued to the shaft.
Fig. 12
TO DISMANTLE
1. Back off the stop screw using an Allen key.
2. Screw off the eccentric lock ring (usually counter to the direction of
rotation of the fan). Mark the position of the bearing on the shaft.
Remove the support arm.
3. The bearing is glued to the shaft. Use an extractor tool to remove the
bearing from the shaft. Fasten the claws of the extractor tool to the
inner ring of the bearing. The bearing can also be removed by tapping
the inner ring of the bearing with a hammer.
TO REFIT
1. Wipe the inner surface of the bearing to remove the protective film.
Put the bearing into the bearing damper.
2. Mount the support arm on the bearing and bearing damper.
3. Clean the shaft carefully. Apply glue (Loctite 603) to the shaft. Fit the
support arm with bearing at the marked position on the shaft. Secure
the support arm to the fan casing.
4. Fit the eccentric lock ring to the inner ring of the bearing and turn it
firmly by hand in the direction of rotation of the fan until the lock ring is
locked in position.
5. Tighten the stop screw using an Allen key. If you can measure the
torque, do not exceed the value specified in the table below.
Excessive torque can cause the inner ring of the bearing to crack.
Fan size
022
025
028
031
035
040
045
050
Torque
(Nm)
4 4 4 4 4 4 4 4 7 7 7 7 7 7 7 7
