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Bombas Ideal, S.A.
13.- OPERATING ANOMALIES
ANOMALY
1. The pump does not lift
water.
2.
Insufficient flow
3.
The power consumption
is higher than expected.
4.
The pump drains after
starting.
5.
The stuffing box drips too
much.
CAUSE
1.1. Rotating the wrong way.
1.2. Pump not primed.
1.3. Low rotating speed.
1.4. Manometric head higher than
initially considered for the pump.
1.5. Suction head too high.
1.6. Impeller conduit blocked.
1.7. Air getting into suction pipe.
1.8. Insufficient submergence.
2.1. Foot valve partially blocked.
2.2. Insufficient submergence .
2.3. Air getting into suction line.
2.4. Impeller partially jammed.
2.5. Air pockets in suction line.
2.6. Large suction head.
Air getting in stuffing box.
2.8. Rotating direction changed.
2.9. Internal parts worn.
2.10. Leaks on delivery pipes
3.1 Manometric head is lower that
initially considered for the pump.
3.2 Specific gravity and viscosity over
what is expected.
3.3. Stuffing box too tight.
3.4. High speed.
3.5. Excessive consumption.
4.1 Excessive suction head.
4.2. Air taking through the stuffing box. 4.2 Apply 2.7.
4.3. Air taking through
line.
4.4. NPSH
< NPSH
r
d
5.1. Lack of packing, this is worn or
not appropriate.
5.2. Shaft worn, stuffing box bush
scratched.
5.3. Mechanical closure worn.
SOLUTION
1.1 Change connections of electric motor.
Change position of explosion engine.
1.2 Foot valve leaking. Leaks in gaskets or
suction piping. Check these parts.
1.3 Check the speed with a tachometer,
speed up the engine. Electric motor.
Check the reason for this low speed
(excessive
frequency).
1.4 Increase the rotation speed of the
pump
diameter.
1.5 Take the pump closer to the water
level. Change the pump for another
with less NPSH
suction piping.
1.6 Unblock the impeller conduits.
1.7 Test pressure the suction pipeline,
including the pump and observe any
liquid leak.
1.8 Extend the suction pipeline increasing
the submergence.
2.1 Clean.
2.2 Submerge
Reduce the flow.
2.3 Apply 1.7.
2.4 Apply 1.6.
2.5 Change
pipeline. Use air drain keys.
2.6 Apply 1.5.
2.7 Test pressure the suction pipeline,
including the pump and observe any
liquid leak.
2.8 Apply 1.1.
2.9 Change the worn parts.
2.10 Test pressure the pipe and repair the
leaks
3.1 Reduce the diameter of the impeller.
3.2 Reduce the flow with the delivery
valve or change the motor.
3.3 Loosen the stuffing box nuts.
3.4 Reduce speed. Reduce the impeller
diameter
3.5 Check the fastening of the terminals.
Check the mains voltage and make
sure the shaft turns gently by hand.
4.1 Apply 1.5.
the suction
4.3 Apply 1.7.
4.4 Reduce the NPSH
increase the NPSH
enquire at technical service.
5.1 Add packing. Fit the right sort.
5.2 Grind the shaft or box bush. Change
the axle or change the box bush.
5.3 Replace with a new one.
consumption
or
or
increase
the
impeller
. Reduce leaks in the
r
the
foot
valve
the
arrangement
of
of the pump,
r
of the system,
d
24
low
more.
the
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