Preventative Pump Maintenance; Maintaining The Pump's Motor; Motor Lubrication - Grundfos CR Installation And Operating Instruction Manual

8. Preventative pump maintenance

At regular intervals depending on the conditions and time of
operation, the following checks should be made:
1. Pump meets required performance and is operating smoothly
and quietly.
2. There are no leaks, particularly at the shaft seal.
3. The motor is not overheating.
4. Remove and clean all strainers or filters in the system.
5. Verify the tripping of the motor overload protection.
6. Check the operation of all controls. Check unit control cycling
twice and adjust, if necessary.
7. If the pump is not operated for unusually long periods, the unit
should be maintained in accordance with these instructions. In
addition, if the pump is not drained, the pump shaft should be
manually rotated or run for short periods of time at monthly
intervals.
8. To extend the pump life in severe duty applications, consider
performing one of the following actions:
– Drain the pump after each use.
– Flush the pump, through system, with water or other fluid
that is compatible with the pump materials and process
liquid.
– Disassemble the pump liquid components and thoroughly
rinse or wash them with water or other fluid that is
compatible with the pump materials and process liquid.
If the pump fails to operate or there is a loss of performance, refer
to Section 15. Diagnosing specific problems.

9. Maintaining the pump's motor

Warning
Do not touch electrical connections before you
first ensure that power has been disconnected.
Electrical shock can cause serious or fatal injury.
Only qualified personnel should attempt
installation, operation, and maintenance of this
equipment.
9.3 Recommended lubricant
Severity of service
Standard
Severe
Extreme
Note: If pump is fitted with a bearing flange that requires grease, see the stickers on either the bearing flange or coupling guards for
proper grease type and greasing schedule.
16
Ambient temp. (max.)
+104 °F (+40 °C)
+122 °F (+50 °C)
>122 °F (+50°C)
or Class H insulation
9.1 Motor Inspection
Inspect the motor at regular intervals, approximately every 500
hours of operation or every three months, whichever occurs first.
Keep the motor clean and the ventilation openings clear.
The following steps should be performed at each inspection:
1. Check that the motor is clean. Check that the interior and
exterior of the motor is free of dirt, oil, grease, water, etc. Oily
vapor, paper, pulp, textile lint, etc. can accumulate and block
motor ventilation. If the motor is not properly ventilated,
overheating can occur and cause early motor failure.
2. Use an Ohmmeter ("Megger") periodically to ensure that the
integrity of the winding insulation has been maintained.
Record the Ohmmeter readings. Immediately investigate any
significant drop in insulation resistance.
3. Check all electrical connectors to be sure that they are tight.

9.2 Motor Lubrication

Electric motors are pre-lubricated at the factory and do not
require additional lubrication at start-up. Motors without external
grease fittings have sealed bearings that cannot be re-lubricated.
Motors with grease fittings should only be lubricated with
approved types of grease. Do not over-grease the bearings.
Over-greasing will cause increased bearing heat and can result in
bearing/motor failure. Do not mix petroleum grease and silicon
grease in motor bearings.
Bearing grease will lose its lubricating ability over time, not
suddenly. The lubricating ability of a grease (over time) depends
primarily on the type of grease, the size of the bearings, the
speed at which the bearings operate and the severity of the
operating conditions.
Good results can be obtained if the following recommendations
are used in your maintenance program. It should also be noted
that pumps with more stages, pumps running to the left of the
performance curve, and certain pump ranges may have higher
thrust loads. Pumps with high thrust loads should be greased
according to the next service interval level.
Environment
Clean, little corrosion
Moderate dirt, corrosion
Severe dirt, abrasive dust,
corrosion
Approved types of grease
Grundfos ML motors are greased
for life or will have the grease type
on the nameplate. Baldor motors
are greased with Polyrex EM
(Exxon Mobile).