ITT Goulds Pumps 3409, Инструкция по установке, эксплуатации и обслуживанию

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Symptom Cause Remedy
The pump leaks ex-
cessively at the stuff-
ing box. The shaft is bent. Straighten the shaft or replace it if necessary.
The pump and driver are not aligned
properly. Realign the pump and driver.
The bearings are worn out or improper-
ly lubricated. Inspect the bearings and replace them if necessa-
ry.
The motor requires ex-
cessive power. The discharge head has dropped be-
low the rated point and is pumping too
much liquid. Install a throttle valve. If this does not help, then
trim the impeller diameter.
If this does not help, then consult an ITT represen-
tative.
The liquid is heavier than expected. Check the specific gravity and viscosity.
The shaft is rotating in the wrong direc-
tion. Change the rotation. The rotation must match the
arrow on the bearing housing or pump casing.
The impeller is damaged. Inspect the impeller and replace it if necessary.
Rotating parts are binding. Check the internal wearing parts for proper clear-
ances.
The shaft is bent. Check the deflection of the rotor by turning it on the
bearing journals. The total indicator runout must
not exceed 0.05 mm | 0.002 in. on the shaft and
0.10 mm | 0.004 in. on the impeller wearing sur-
face.
The motor speed is too high. Check the motor voltage or the steam pressure re-
ceived by turbines. Make sure the motor speed
matches the speed on the nameplate.
The stuffing box is improperly packed. Check the packing and repack the stuffing box. If
the packing is too tight, then try releasing the gland
pressure and tightening again.
The bearings are worn out or improper-
ly lubricated. Inspect the bearings and replace them if necessa-
ry.
The running clearances between the
wear rings are incorrect. Check for the proper clearances. Replace the cas-
ing or impeller wear rings if necessary.
There is excessive pipe strain on the
pump casing. Relieve the strain and check the alignment. Con-
sult ITT if necessary.
The amount of available NPSH is not
sufficient. 1. Increase the positive suction head by low-
ering the pump or increasing the suction
pipe and fittings size.
2. Sub-cool the suction piping at the inlet to
lower the temperature of liquid that is en-
tering the pump.
3. Pressurize the suction vessel.
The pump and driver are not aligned. Realign the pump and driver.
The suction inlet is not submersed
deep enough. If the inlet cannot be lowered or if the problem per-
sists after the inlet is lowered, then chain a board
to the suction pipe. The board will be drawn into
the eddies and smother the vortex.
The casing is distorted due to exces-
sive strains from the suction and dis-
charge piping. Check the alignment. Examine the pump for rub-
bing between the impeller and the casing. Replace
damaged parts and redo the piping.
7.1 Troubleshooting
Model 3409 Installation, Operation, and Maintenance Manual 61