18
DC Motors
In general, mixing of greases is not recommended. If an incompatible
grease is used, the lube system must be repacked completely with the
new grease.
5.
Wipe away any excess grease at the grease drain or relief and replace
drain plugs.
Repacking Bearings or Greasing New Bearings
When existing bearings have been completely cleaned of old grease or
when bearings are replaced, use this procedure for packing the bearing.
1.
Apply one bead of grease all around inboard side of bearing between
bearing and inner cap, making sure that grease adheres to balls or rollers.
2.
Apply one bead of grease all around outboard side of bearing, making
sure grease adheres to balls or rollers.
3.
Completely fill grease inlet and outlet passage holes with grease.
4.
Fill outboard bearing cavity 60% to 90% full of grease.
5.
If possible, rotate shaft of assembled machine at least three revolutions
by hand to distribute grease within bearings before starting motor.
Bearings
These motors are designed to provide a mounting for anti-friction bearings
to give:
•
Maximum protection to windings and interior of machine by preventing
grease leakage from bearing housing.
•
Maximum protection to bearings against excess lubricant, insufficient
lubricant, dirt and moisture.
Various types of anti-friction bearings are used in the wide range of frames
as needed to meet specific load, speed and service requirements.
Most commonly used bearings are:
•
Single row, open ball bearings for coupled and belted duty for frames
C180ATZ. Frames DC180ATZ and DC210ATZ have a single-shielded
bearing on the commutator end.
Frequent bearing checks are recommended. If temperatures become
excessive, investigate immediately for the cause. Total bearing temperatures
should not exceed 90 degrees C (194 degrees F). Causes for high bearing
temperature are:
•
Contaminated grease.
•
Insufficient grease or excessive amount.
•
Incorrect grease.
•
Excessive load or thrust due to misalignment or motor overload.
•
Loose bearings.
•
Bearing failure.
•
Excessive ambient temperature.
