Siemens induction motors- generators cgii Manuel D’Utilisation

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Sealing Parts 
Even though joints may seem to match perfectly, 
minute clearances exist through which oil may leak. . 
 
Apply sealant as follows: 
 
1.  Surfaces shall be clean of dirt, grease, and oil 

sealant.  Use a non-oil base solvent if necessary. 

2.  The mating surfaces should be flat with no nicks 

raised above the surface.  There should be no 
gap when mating surfaces are together. 

3a. For 500, 580, and 1120 frames, apply a small 

bead of silicone RTV at the bearing housing 
parting surfaces. Loctite 518 may be used in 
replace of RTV in environments where silicon is 
prohibited. Do not apply too much sealant as 
excess will be squeezed out and get into 
labyrinth seals, bearing, oil cavities, etc. Apply a 
uniform, thin layer (about 0.05" thick) of Curil T* 
to the floating oil seal surfaces that mate with the 
bearing housing. Allow Curil T to cure on the 
seals for 15 minutes before insertion into bearing 
housing.  

3b. For 680 and 800 frames, apply a small bead of 

silicone RTV to all mating surfaces of parts where 
oil is present, including fixed oil seals and parting 
lines. 

4. Assemble 

parts. 

 

*CURIL-T may be ordered through Siemens Customer Service in 
Norwood, Ohio.  Part number 53-688-487-001 should be used for 
ordering purposes. 

 
 

Grease Lubricated Antifriction Bearings 
 

 

A common mistake is over-lubrication of bearings.  
When grease is added without removing the drain 
plug, the excess grease may be forced into and 
through the inner bearing cap and thrown on to the 
windings.  If bearing is over-lubricated, bearing could 
run hot, and may lead to failure. 

 
All antifriction bearing motors will have an affixed 
plate with lubricating instructions.  The instructions on 
this plate should be followed to achieve optimum 
bearing life and to avoid consequential damage to 
rotating parts. 

 
The frequency of relubricating bearings depends on 
three factors - speed, type of bearing, and service. 
 
Operating environment or application may dictate 
more frequent lubrication. 
 
Relubricate with the type of grease specified on the 
lubrication plate mounted on the motor, or a 
compatible grease.  Mixing of non-compatible 
greases can cause bearing failure. 
 
Higher stator temperatures will result in increased 
bearing temperatures.  Bearing temperatures should 
not exceed the limits as stated in Typical Motor 
Control Settings.  For specific recommendation, 
consult factory. 
 
Procedure for relubrication: 
 
1.  Stop the motor and lock out the switch. 
2.  Thoroughly clean the grease inlet fitting or plug.  

If the motor has plug, remove plug and clean the 
inlet. 

3.  Remove the drain plug and clean out any 

hardened grease. 

4.  Slowly pump the correct amount of grease into 

the grease inlet, per the lubrication plate mounted 
on the motor. 

5.  Start motor and allow to run at least one (1) hour 

to expel any excess grease from the drain 
opening before re-installing the drain plug. 

6.  Stop the motor and lock out the switch. 
7.  Re-install the drain plug. 
8.  Put the motor back in operation. 
 
The amount of grease for bearings may be calculated 
by the following: 

G = 0.1 x D x B 

 

 

Where: 

G = Amount of grease in fluid ounces 

 

D = Outside diameter of bearing in inches 

 

B = Width of bearing in inches