| Don't
throttle the pump suction to reduce its delivery |
|
This practice causes the pump to cavitate
. Throttling the discharge is just as easy and is not harmful.
|
| Don't
run a pump dry |
|
Liquid is necessary to lubricate and cool
the internal clearances . A pump running dry will generally
overheat and seize . This means - NEVER START A PUMP WITH
THE SUCTION VALVE CLOSED.
|
| Don't
run a pump at excessively low flows |
|
First, unless reduced capacity operation
is normal for the service the pump design may be one which
results in a high radial reaction and shaft failure . Second
, the hydraulic design may be such that actual impeller failure
will result . Third, part of the power consumed by the pump
goes into heating the liquid and if insufficient flow is available
, the pump will overheat and seize . As a rule of thumb, the
minimum flow to protect against overheating is about 30 gallons
per minute for every 100 horsepower at shut-off .
|
| Make
hourly observations |
|
Watch for irregularities in performance .
Investigate changes in the sound of a running pump immediately
. Observe bearing temperatures and stuffing box operation
hourly . Check pressure gauges and the flow indicator hourly
to see whether pressure and flow correspond to normal operating
conditions .
|
| Don't
stop leakage from stuffing box completely |
|
Some leakage is necessary to provide lubrication
and cooling of the packing .
|
| Don't
use excessive lubricant with anti-friction bearing |
|
If using grease , the bearing , should be
about one third packed with grease . If oil lubricated , the
level should not exceed that marked on the oil gauge
|
| If
stuffing boxes need repacking , use new packing |
|
Do not add one or two rings to the old packing
. This may displace the seal-cage , if used , and plug the
sealing liquid opening .
|
| Semi-annual
inspection |
|
Check for free movement of stuffing box glands,
clean and oil the gland bolts and nuts, and inspect the packing
. Check the pump and driver alignment and correct it , if
necessary . Drain and refill oil lubrication bearings . Check
grease- lubricated bearings for suitable consistency and correct
amount of grease .
|
| Annual
Inspection |
|
Thoroughly inspect a pump annually . Remove
bearings to clean and examine them for flaws . Remove the
packing and examine the sleeves for wear . Disconnect the
coupling and check alignment . Check and flush the drain ,
sealing water and cooling water pumping . Recalibrate all
instructions and run full tests of pump performance
|
