11371757 Installation, operation and maintenance manual – Squirrel cage motor – M line – Vertical
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7.9.2.1
Lubrication instructions
Oil drainage: When it is necessary to change the bearing
oil, remove the oil outlet plug (3) and drain the oil
completely.
To fill the bearing with oil:
Close the oil outlet with the plug (3);
Remove the plug from the oil inlet or from the filter (1);
Fill it with the specified oil up to the level indicated in the
oil sight glass.
NOTES
1.
All threaded holes that are not used
must be closed with plugs and no fitting
may present leaks;
2.
The oil level is reached when the
lubricant can be seen approximately in
the middle of the sight glass;
3.
The use of a larger amount of oil will not
damage the bearing; but it can cause
leaks through the shaft seals;
4.
Never use hydraulic oil or mix it with the
bearing lubricant oil.
7.9.2.2
Oil type
The type and quantity of lubricant oil to be used are
specified on the nameplate affixed to the motor.
7.9.2.3
Oil change
The bearing oil change must be done according to the
intervals, which depend on the bearing operating
temperature, shown in Table 7.5:
Table 7.5: Oil change intervals
Bearing operating
temperature
Bearing oil change
intervals
Below 75 ºC
20,000 hours
Between 75 and 80 ºC
16,000 hours
Between 80 and 85 ºC
12,000 hours
Between 85 and 90 ºC
8,000 hours
Between 90 and 95 ºC
6,000 hours
Between 95 and 100 ºC
4,000 hours
The lifespan of the bearings depends on their operating
conditions, on the motor operating conditions and on the
maintenance procedures.
Proceed according to the following directions:
The oil selected for the application must have the
proper viscosity for the bearing operating temperature.
The type of oil recommended by WEG already
considers these criteria;
Insufficient quantity of oil may damage the bearing;
The minimum recommended oil level is reached when
the lubricant can be seen in the lower part of the oil
sight glass with the motor stopped.
ATTENTION
The oil level must be inspected daily and
must remain in the middle of the oil sight
glass.
7.9.2.4
Bearing operation
The system start, as well as the first hours of
operation, must be monitored carefully.
Before starting, check:
If the used oil complies with the specification on the
nameplate;
The lubricant characteristics;
The oil level;
The alarm and trip temperatures set for the bearing.
During the first start, it is necessary to stay alert for
unusual vibrations or noises. If the bearing does not
operate in a silent and smooth way, the motor must be
shut down immediately.
The motor must operate for some hours until the bearing
temperatures stabilize. In case of overheating of the
bearings, the motor must be shut down for inspection of
the bearings and temperature sensors.
Check if there is no oil leak through the plugs, gaskets or
shaft end.
