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Changing
the bearings
Bearings
Disassembling
• Dismantle the motor according to
page 40.
• After removing the end shield, remove the
rotor.
• Great care should always be taken during
bearing assembly / disassembly to avoid any
damage to the bearing seating on the shaft.
• The bearing must be removed with a pur-
pose-designed extractor. See figure below.
Figure 17. Disassembling a bearing using a purpose-designed extractor.
Assembling
• Carefully clean bearings and the inside of the
bearing covers.
• Then place the inner bearing cover on the
shaft.
• Heat the new bearing to 100 °C by induction,
by placing in an oven or dipping it in an oil
bath. Note! The new bearing must be of the
same type as shown on rating plate.
• Fit the bearing on the shaft and hold it
against the shoulder for 60 – 90 seconds.
• Remove the pressure applied and check that
the inner ring does not rotate on the shaft
• Fill the bearing with grease. Note! Use only
grease that fulfils ABB requirements, see
page 25.
• Fill the bearing covers 2/3 full before
assembly.
• Reassemble the motor according to
page 40.
Standard bearings and roller bearings
The table below shows standard bearings and
roller bearings for different DMI shaft heights.
Differences may occur due to special design
depending on application. The bearings fitted
to each specific motor are shown on. the rating
plate.