ITT Goulds Pumps 3500XD, Инструкции по установке, эксплуатации и обслуживанию

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• Amp meter or percent motor load for Model 3500XD drive motor
• Signal lights showing Model 3500XD running, vacuum pump running, and air removal valve posi-
tion
• Alarms for vacuum pump not running, Model 3500 shutdown, seal water flow, and standpipe high
and low level
Monitors at the pump location include:
• Seal water flow to the Model 3500XD, vacuum pump, and vacuum chamber
• Vacuum level in the air removal system
The actual value of the level control (LCI) should be within the range of ± 5% of the set value. The
normal output signal should be as indicated in the IOM Appendix for the specific service. If it is con-
tinuously lower than the set value, the regulation of the level control valve may be disturbed.
If the pressure indicator (PI) in the air removal system varies ± 1 ft., the set value of the standpipe level is
too low, the pulp in the standpipe contains large amounts of air, or the level control is not working proper-
ly.
The Model 3500XD motor load should be relatively stable, although consistent variations would be con-
sidered normal. Sudden changes in motor load usually indicate that more air is entering the pump from
the standpipe, which can be corrected by increasing the standpipe level set point.
Usually the main cause for pumping problems is that the stock in the standpipe contains large void
areas, the stock is bridging in the standpipe, the stock consistency is too high, or because changes in
consistency, pH or temperature have caused a significant increase in the discharge piping head loss.
The above causes can be remedied by increasing the dilution water flow.
Table 4: Troubleshooting the model 3500XD standpipe installation
Problem Symptoms Possible cause Solutions
Pump will not start pump-
ing Amps to drive motor normal Control valve LCV does not
open Check that the supply air
pressure to the actuator is
sufficient
Discharge pipe plugged Open by flushing, check that
any manual valves in the
discharge pipe are open
Amps to drive motor below
normal ARV has not opened Open manually and check
setting on LCV limit switch
Pressure in air removal pip-
ing too high Check that the vacuum
pump is running and the set-
ting of the vacuum relief
valve
Air removal pipe plugged
with stock Flush air removal piping
Pump discharge flow too
low Level control valve 100%
open Standpipe dilution valve not
operating, or dilution water`
pressure too low Check that dilution valve is
operating, check dilution wa-
ter pressure
Flow too high compared to
pump capacity Check pump and motor
speed, check V belts if V
belt driven
Pump power consumption and
air removal pressure unstable Level in standpipe too low,
or air removal pressure too
high Raise the level set point in
the standpipe, or reduce
pressure in air removal pip-
ing
Stock discharge pipe vi-
brates Power consumption and air
removal pipe pressure stable Discharge piping inade-
quately supported Improve discharge pipe sup-
ports and anchors
5.7 Monitoring during operation
32 3500XD Installation, Operation and Maintenance Instructions