ENGLISH
963857101_G
24
24
Relubrication intervals recommended 3.000 hours, when regreasing use 50 grams of grease.
- Always clean regreasing device before forcing in the grease, remove the exhausted grease plug on the endshild and turn the rotor in
order to distribute the new grease inside the bearing.
- Immediately after regreasing the bearing temperature rises for a while, and than drops to normal values after the grease has been
uniformly distributed and the exceeding grease displaced from the bearing.
- After regreasing close the exhausted grease opening whit the plug.
5.3 Dismantling operations
Before dismantling the machine, examine the views in cross-section.
Check that the lifting means available are suitable for the movement of all parts which have to be handled.
Check also that all the working conditions are suitable to operate without dangers for safety of personnel.
On disassembly, mark the components if believed necessary, in order to identify their correct positions during successive
assembly.
Then uncouple the generator from the prime mover, removing the bolts securing the flange and feet; remove the bolts fixing the
coupling and disconnect the terminals of the power leads on the terminal board.
- Remove the generator from the prime mover.
- Disconnect the leads whites (+) and (-) connecting the exciter stator to the voltage regulator, and take the clamps off.
For two bearing generators:
- Remove the half coupling from shaft extension and remove the key (223).
- Remove the bolts fixing the inner D-end bearing cap (131) to the shield.
- Remove the D-end screen protective elements (49).
- Remove the bolts fixing the shields (4-5) to the frame, then remove the shields having care to sustain the rotor in order it will
not fall heavily on the stator.
- Using proper lifting means, remove the rotor (3) from the main stator, through the D.E. side, taking special care to avoid any
damage to the windings.
For single bearing generators:
- Remove the bolts fixing the N.D.E. shield (5) to the frame.
- Dismantle the shield and remove the rotor (3) from the main stator, through the D.E. side, taking special care to avoid any
damage to the windings.
ATTENTION! :
It should be remembered that the exciter stator is fixed to the N.D.E. end-shield: special care should be taken to avoid
any damage to its windings when removing the N.D.E. shield; furthermore be sure the connections or the exciter stator are free to slide
out from terminal box.
If a bearing needs to be replaced, remove it with a suitable puller.
Where present use the inner cover of the bearing.
5.4 Reassembly operations
Carry out the operations described above for dismantling in reverse order. If the end-shield have been removed, the fixing screws have
to be fixed with Loctite
®
type 243 (on the threaded surface).
If a bearing was removed, always install a new one.
To make assembly easier, the bearings should be heated to about 80 - 90°C.
ATTENTION!
: bearings should be assembled with the utmost care in order not to damage them.
If a locking element has to be replaced, make sure that the new one is of the same type and same resistance class of the original.
The following table indicates the tightening torques valid for locking screws and nuts:
Tightening torques in Nm ±10%
Application
Thread diameter
M 5
M 6
M 8
M 10
M 12
M 16
M 20
M 24
M 27
M30
Fixing of electrical connections
/
8
16
32
60
150
/
/
/
/
Fixing
of
components
(end-shields,
bearing caps, etc).
Fixing of feet or flange.
5
11
26
48
85
206
400
700
1030
1420
