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•
The bearings are washed, dried and pre-greased with suitable and high quality
rolling bearing grease before assembly.
•
The disassembly and mounting of the bearings does not damage the bearings.
The bearings must be removed by using pullers and fitted by heating, or using
special tools for the purpose.
NOTE: If there is a need to change bearings, please contact ABB After Sales,
see After Sales contact information in
Chapter 9.1.5. After Sales contact
information.
NOTE: WHEN DISMANTLING THE MACHINE, ALWAYS CHANGE
THESE CLOSED BEARINGS.
NOTE: Remember to tighten the screws correctly. When tightening screws,
following procedure shall be followed:
•
Clean the thread of the screw
•
Use appropriate screw locking agent
•
Tighten the bolts in crossing order in two phases with the torque wrench
(the tightness of fastening refer to
Table 7-10. General tightening
torques
)
For more information see
Chapter 7.4.4. The tightness of fastenings
.
7.5.1 Bearing construction
Closed anti-friction bearings
Closed bearings cannot be re-greased and only maintenance operation is to
regularly check cleanliness of the bearing, keep bearing clean, protect surface of
the bearing from corrosion and visually check the condition of the bearing.
Re-greasable anti-friction bearings
In order to operate reliably, bearings must be satisfactorily lubricated to prevent
direct metallic contact between rolling elements, bearing and cage races, to
prevent wear and to protect surfaces from corrosion. To ensure reliable operation,
the bearings should be regularly re-greased with high-quality rolling bearing
grease.
The choice of grease, greasing and cleaning intervals must therefore be
scrupulously respected. All this information is given on the lubrication plate.
The best operating temperatures are obtained when the bearing receives the
minimum necessary quantity of lubricant to ensure reliable lubrication. It is
therefore important that the machine manufacturer's instructions are respected.
Excess lubricant quickly increases the operating temperature, particularly at high
rotation speeds.
When it is necessary to change from one type of grease to another, for any reason
whatever, the mixability of lubricants must be taken into consideration. If
incompatible greases are mixed, the consistency may become very different and
the maximum usage temperature of the mixture may become low enough to cause
a bearing failure.
New grease must always be added to bearings while they are still lubricated
satisfactorily, and always with the machine in operation. Grease shall be added in
accordance with information given on the greasing plate.
