Manual for Induction Motors and Generators
72 -
Maintenance
3BFP 000 050 R0101 REV E
***Following chapter for bearing type: Rolling bearing
7.5.3 Rolling bearings
7.5.3.1 Bearing construction
In normal operating conditions, rolling bearings require little maintenance. To ensure reliable
operation, the bearings should be regularly re-greased with high-quality rolling bearing grease.
7.5.3.2 Bearing plate
All machines are supplied with bearing plates attached to the machine frame. The bearing plates
provide bearing information, such as:
•
Bearing type
•
Lubricant used
•
Re-greasing interval, and
•
Re-greasing amount.
For more details regarding the bearing plate, see
NOTE: It is essential that the information provided on the bearing plate is taken into account
when using and maintaining the machine.
7.5.3.3 Re-greasing intervals
Rolling bearings of electrical machines need to be re-greased at regular intervals. The re-
greasing interval is found on the bearing plate.
NOTE: Regardless of the re-greasing interval, the bearings need to be re-greased at least once
per year.
The re-greasing intervals are calculated for an operating temperature of 70°C (160°F). If the
operating temperature is lower or higher than the assumed, the re-grease interval has to be
altered accordingly. Higher operating temperature decreases the re-greasing interval.
NOTE: An increase in the ambient temperature raises the temperature of the bearings
correspondingly. The values for the re-greasing interval should be halved for every
15°C (30°F) increase in bearing temperature and may be once doubled for a 15°C
(30°F) decrease in bearing temperature.
Re-greasing intervals for frequency converter drives
Higher speed operation, e.g. in frequency converter applications, or lower speed with heavy
load will require shorter lubrication intervals or a special lubricant. Consult manufacturing ABB
factory After Sales department in such cases.
NOTE: The constructional maximum speed of the machine must not be exceeded. The
suitability of the bearings for high-speed operation must be checked.