Instructions For Lubrication; Procedures For Relubrication Of Bearings; Exchange Of Bearings; Alternator With Single Bearing - B15T - WEG AG10 Series Installation, Operation And Maintenance Manual

ATTENTION
1. WEG does not recommend the use of
any grease different from the original
grease of the alternator.
2. When the bearing is opened, inject the
fresh grease through the grease nipple to
eject the old grease found in grease inlet
tube and applying new grease to the
bearing, the inner ring and outer ring by
completing three quarters of the voids.
3. Never clean, the bearing with a cotton
cloth as it may release lint serving as a
solid particle.
4. Proper lubrication is important, that is,
the grease applied correctly and in a
suitable quantity, for both a poor
lubrication as lubrication excessive bring
the bearing adverse effects.
5. Excessive lubrication entails temperature
rise due to the large resistance offered to
the movement of rotating parts and,
mainly, due to beating of grease, which
ultimately completely loses its
characteristics of lubrication.
NOTE
WEG is not responsible for the change of
grease or for any damages arising from the
change.
6.5.3

Instructions for lubrication

The lubrication system is designed such that during
relubrication of bearings, all of the old grease is removed
of bearings and expelled through a tube which enables the
output of the same, but prevents the entry of dust or other
hazardous contaminants into the bearing.
This drain also prevents damage to the bearings due to
the well known problem of excessive relubrication.
It is advisable to perform relubrication with the alternator in
operation, so as to ensure the renewal of grease in the
bearing housing. If this is not possible due to the presence
of parts near the grease nipple (pulleys etc.), which can
jeopardize the physical integrity of the operator, proceed
as follows:

With the alternator stopped inject approximately half the
total amount of grease planned and operate the
alternator for approximately 1 minute at full speed;

Stop the alternator and inject the remaining grease.
Injection of all grease with the alternator stopped can
cause penetration of the lubricant to the inside of the
alternator.
ATTENTION
It is important to clean the grease cups prior
to lubrication, to prevent foreign material
from being drawn into the bearing.
12638144 Installation, operation and maintenance manual – Synchronous Alternator – AG10 line - Horizontal l 39
NOTE
The data of bearings, quantity and type of
grease and lubrication intervals are
informed in a bearing nameplate, fixed on
the alternator. Verify this information before
making the lubrication.

The lubrication intervals informed in the nameplate
consider a bearing working temperature of 70°C.

Based on the operating temperature ranges listed
below, apply the following correction factors for
lubrication intervals of bearings:

Operation temperature lower than 60 °C: 1,59

Operation temperature from 70 °C to 80 °C: 0,63

Operation temperature from 80 °C to 90 °C: 0,40

Operation temperature from 90 °C to 100 °C: 0,25

Operation temperature from 100 °C to 110 °C: 0,16
6.5.4

Procedures for relubrication of bearings

1. Remove the cover of the drain;
2. Clean with a cotton cloth around the grease cup hole;
3. With the alternator running, inject grease until new
grease begins to flow from the drain or until the
amount of grease informed in Table 6.1 has been
introduced;
4. Operate the alternator long enough so that excess
grease flow through the drain;
5. Inspect the bearing temperature to make sure that
there was no significant change;
6. Replace the cover of the drain.
6.5.5

Exchange of bearings

ATTENTION
For security, the exchange of bearings must
be done with the alternator uncoupled from
the driving machine.

6.5.5.1 Alternator with single bearing - B15T

To disassemble the alternator rear part and have access
to the bearing, follow the instructions below:
1. Release cables (F+) and (F-) in the terminal box;
2. Remove the exciter cover;
3. Loose the cables of the main rotor connected to the
rectifier bridge;
4. Remove the screws that hold the exciter rotor on shaft
and remove it manually (AG10 250, 280, 315 and
355);
5. Remove the rectifier bridge along with the bush (AG10
400)
6. Remove the screws of the rear cover attached to the
frame and remove this cover along with the exciter
stator;
7. Replace the bearing, according to the procedure
described on 6.5.5.3 and assemble the alternator.
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