Siemens 680 - Manual (Page 21)

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Maintenance
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.
Bearing Lubrication
Grease Lubricated Antifriction Bearings
NOTE
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