Pump maintenance

Daily Pump Maintenance

• Check coupling bushes/rubber spider.
• Check stuffing box, gland etc.
• Clean the pump, motor and other accessories. 

Routine observations of abnormalities

The pump operator should be watchful and should take appropriate action on any abnormality noticed in the operation of the pumps. Particular attention should be paid to following abnormalities.

• Oil leakage from bearings
• Leakage from stuffing box or mechanical seal
• Changes in sound of running pump and motor
• Changes in voltage
• Changes in current
• Abrupt changes in bearing temperature.
• Overheating of motor, starter, switch gear, cable etc.
• Changes in pressure gauge readings 

Monthly pump maintenance

• Check free movement of the gland of the stuffing box; check gland packing and replace if necessary.
• Clean and apply oil to the gland bolts.
• Inspect the mechanical seal for wear and replacement if necessary.
• Check condition of bearing oil and replace or top up if necessary. 

Quarterly Pump Maintenance

• Tighten the foundation bolts and holding down bolts of pump and motor mounting on base plate or frame.
• Check vibration level with instruments if available; otherwise by observation.
• Clean flow indicator, other instruments and appurtenances in the pump house.
• Check alignment of the pump and the drive. The pump and motor shall be decoupled while correcting alignment, and both pump and motor shafts shall be pushed to either side to remove effect of end play in bearings.
• Clean oil lubricated bearings and replenish with fresh oil. If bearings are grease lubricated, the condition of the grease should be checked and replaced/replenished to the correct quantity. An anti-friction bearing should have its housing so packed with grease that the void space in the bearing housing should be between 1/3 to 1/2. A fully packed housing will overheat the bearing and will result in reduction of life of the bearing. 

Yearly Pump Maintenance

• Examine shaft sleeves for wear or scour and necessary rectification. If shaft sleeves are not used, shaft at gland packing’s should be examined for wear.
• Check impeller hubs and vane tips for any pitting or erosion.
• Check interior of volute, casing and diffuser for pitting, erosion, and rough surface.
• Clean and flush bearings with kerosene and examine for flaws developed, if any, e.g. corrosion, wear and scratches. Check end play. Immediately after cleaning, the bearings should be coated with oil or grease to prevent ingress of dirt or moisture.
• Check stuffing box, glands, lantern ring, mechanical seal and rectify if necessary.
• Clean bearing housing and examine for flaws, e.g. wear, grooving etc. Change oil or grease in bearing housing.
• Check clearances in wearing ring. Normally, if the clearance in wearing rings increases by about 100% for small pumps and 50-75% for large pumps the rings shall be renewed or replaced to restore to the original clearance.
• Conduct performance test of the pump for discharge, head and efficiency.
• Check vibration level.
• All vital instruments i.e. pressure gauge, vacuum gauge, ammeter, voltmeter, watt meters, frequency meter, tachometer, flow meter etc. shall be calibrated. 

Record of operations and observations of pump

A log book should be maintained to record the hourly observations, which should cover the following items.

• Current drawn by each pump-motor set and total current drawn at the installation.
• Timings when the pumps are started, operated and stopped during 24 hours.
• Voltage in all three phases.
• Water level in intake/sump.
• Flow meter reading.
• Readings of vacuum and pressure gauges.
• Motor winding temperature.
• Bearing temperature for pump and motor.