Maintenance; Repairing The Pump; Disassembling The Pump-Motor Group; Assembling The Pump-Motor Group - DAB SM series Installationsanweisung Und Wartung

The following cases are possible:
Same pressure, same AMPS obsorbed:
If the gauge readings do not differ substantially
–
from previous readings, the impellers are not worn
and motor rotation is correct.
If the AMPS absorber did not change from the
–
original readings, the pump and motor internal
rubbing did not increase and the percentage of
water suspended sand is not representing a
problem for the pump.
Lower pressure:
Lower pressure means worn impellers, or too low
–
main voltage.
Higher AMPS absorbed:
This usually indicates a strong rubbing by the
–
bearing journals due to suspended solids.
SECOND TEST
Open completely the gate valve.
–
Note the AMPS absorbed.
–
Note pressure as reported by the pressure gauge.
–
Note pump delivery as reported by the flow meter.
–
The following case is possible:
– Pump delivery lower than rated delivery. This can
depend from scaling, from a clogged upstream
valve or from leaks along the pipe line.

8. MAINTENANCE

Periodical maintenance is strictly related to the
–
percentage of water suspended sand.
No maintenance is necessary as long as the
–
pump keeps running efficiently, i.e. pump delivery
keeps above 50% of rated delivery or the AMPS
absorbed do not exceeds the 5% allowance.
In some cases it will be necessary to replace worn
–
parts such as impellers, sealing rings or bearings.
In case of an high sand percentage, we suggest a
–
first inspection after a 1000 running hours.
During long idle periods in the well, the pump /
–
motor groups should be shortly started every 2 or
3 months.
– Making sure the group is still fully submersed.

9. REPAIRING THE PUMP

9.1 Disassembling the pump / motor group
Because of its construction features, the pump and
motor group easily disassembled and re-assembled
with normal metric size shop tools.
ENGLISH
If the pump adopts a non return valve, consider
–
the additional weight of the water-filled column
besides the group weight and use therefore a
suited hoist.
We suggest to employ specialized personnel for
–
assembling and disassembling.
9.2 Assembling the pump / motor group
Check the free rotation of pump and motor
–
rotating parts, paying attention not to damage
them.
The axial joint between pump shaft and motor
–
shaft should
Absolutely avoid kicking the shaft, as that could
damage the thrust bearing.
The pump-motor
–
perfectly, a wrong alignment will unavoidably
cause motor bearing failure and vibrations.
The pump joints are provided with screws to lock
–
the rotating part axially.
The coupling screw for 10" - 12" - 14" motors
should be strongly locked on the motor key.
When coupling 6" - 8" motors, the coupling screw
–
shall be aligned to the hole located on the motor
shaft; after locking, the screw must be unscrewed
half turn and locked in this position by a sealing
product (loctite or similar) or in a mechanical
position positive way (calking), paying attention
not to damage the screw thread. The locking of
the screw on the shaft could cause an
eccentrical rotation of the rotating part and
consequently damage the bearings.

10. DECOMMISSIONING AND

DISMANTLEMENT
When the pump will be permanently stopped and
dismantled, the various materials composing it should
be properly disposed of. It is important to make sure that
no residual polluting liquids are trapped within the pump.
The materials used in pump construction are:
- Steel and cast iron.
- Aluminum.
- Rubber and plastic.
- Copper.
The disposal of polluting liquids and materials should
follow current environmental regulations.
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be installed without
coupling should
forcing.
be done