Series MNKA bearing pedestal assembly 4
Page 18
9250-003-en
Revision 01
TM 10458
Published 06/2022
♦
Using the triangular pyramid on the threaded
rods and an open-end wrench size 13, press
the drive unit out of the lantern chamber. In the
process, turn the threaded rods evenly in al-
ternation.
Attention! Magnetic forces!
Risk of accident!
♦
Transport the drive unit by crane. The ring bolt
on the bearing pedestal flange can be used for
this purpose.
♦
Set up the remaining slide-in unit vertically, with
the impeller pointing downwards.
♦
Remove screws
901/10
and lift off lantern
344
,
can
159
and can insert
158
.
♦
Clamp plain bearing pedestal
339
at the seal-
ing surfaces in a vice.
To avoid damaging the plastic
sealing surfaces, be sure to use
rubberized clamping jaws.
♦
Release impeller
230
and pump rotor
859
by
turning them in opposite directions. Right-
hand thread!
Either two strap wrenches or, better still,
specialist tools (see assembly aid in
section
11.3
) can be used for this purpose.
For magnetic couplings >3540 in-lb (>400 Nm)
the
use
of
the
special
tools
is
generally recommended.
♦
The pump rotor
859
detaches from the pump
shaft
211
. The pump shaft is pulled out of the
plain bearing pedestal
339
with the remaining
component.
♦
This step must be carried out carefully, as
silicon carbide plain bearing parts may be re-
moved unintentionally.
Make sure that no plain bearing parts
fall off. Silicon carbide fractures ea-
sily.
♦
An appropriate Richter device can be used to
remove the
545/1
and
545/2
bearing bushes.
See assembly aids in
section 11.2.
♦
The can
159
and can insert
158
should only be
separated if a component needs to be
replaced. The separation process can be sim-
plified by cooling the unit to approx. 41 °F
(5 °C).
♦
In the case of a vacuum-proof design, separa-
tion of the can unit is not possible because the
can insert and can are bonded together.
7.6.2 Dismantling the drive unit and
long-life lubrication system
♦
Remove socket head screw
914/5
with toothed
lock washer
934/4
and pull off the pump rotor
858
from the drive shaft
213
. If possible, use a
non-magnetizable tool for this purpose.
Attention! Magnetic forces!
Risk of accident!
♦
Remove screws
914/6
and pull off rear bearing
cover
361
.
♦
Remove wave spring washer
953/1
.
♦
Pull or press drive shaft
213
with the rolling
bearings
321/1
and
321/2
out of the bearing
pedestal
330
in the direction of the motor.
♦
To replace the rolling bearings
321/1
and
321/2
, push them off the drive shaft
213
.
♦
Optional
The pump can be equipped with roller
bearings that can be relubricated. In this case,
in bearing pedestal
330
and in rear bearing
cover
361
there is a
421/1
and a
421/2
rotary
shaft seal .
See
section 10.2
.
♦
The mating surfaces of the shaft seals consist
of chromium oxide coated steel rings which
can be replaced at the factory if necessary.
7.6.3 Dismantling the drive unit and oil
bath lubrication system
♦
Remove socket head screw
914/5
with toothed
lock washer
934/4
and pull off the pump rotor
858
from the drive shaft
213
. If possible, use a
non-magnetizable tool for this purpose.
Attention! Magnetic forces!
Risk of accident!
♦
Remove hexagon screw
901/4
and drain the
oil.
♦
Remove screws
914/6
and the rear bearing
cover
361
with shaft seal
421/1
and O-ring
412/1
.
♦
Remove wave spring washer
953/1
.
♦
Pull or press drive shaft
213
with the rolling
bearings
321/1
and
321/2
out of the bearing
pedestal
330
in the direction of the motor.
♦
To replace the rolling bearings
321/1
and
321/2
, push them off the drive shaft
213
.
♦
If necessary, push out the shaft seals
421/1
and
421/2
from bearing pedestal
330
and rear
bearing cover
361
.
♦
The mating surfaces of the shaft seals consist
of chromium oxide coated steel rings which
can be replaced at the factory if necessary.
♦
We recommend replacing the shaft seals
421
each time the bearings are replaced.
