Maintenance; Disassembly; Reassembly; Trouble Shooting - Xylem Goulds VB Serie Manuel D'instructions

MAINTENANCE

FAILURE TO DISCONNECT AND
WARNING
LOCKOUT ELECTRICAL POWER
Hazardous
BEFORE ATTEMPTING ANY
voltage
MAINTENANCE CAN CAUSE SHOCK,
BURNS OR DEATH.
• Motors have permanently lubricated bearings. No
lubrication is possible or necessary. Follow the motor
manufacturer's recommendations for maintenance.
• To REMOVE pump from service drain all pumpage
from pump and piping.
• To RETURN pump to service replace all plugs and
piping using PTFE tape or equivalent on male threads.
• Refer to "OPERATION" section of manual.
VB SERIES DISASSEMBLY
• Place wrenches on adapter (18) and suction head (1),
and unscrew suction head and casing (3).
NOTE: CASING HAS A LEFT HAND THREAD
ON BOTH ENDS AND IS SEALED WITH
O-RINGS (2).
• Remove klip ring (10) from end of shaft (15). The
stages, each comprising a bowl (11), impeller (12) and
diffuser (13) may now be removed. If pump has been
clogged by foreign matter, but otherwise undamaged,
further dismantling may be unnecessary. If shaft assem-
bly (15), shaft seal (17) or motor are to be replaced
proceed as follows:
• Remove plug from rear of motor and hold motor
shaft with screwdriver. Unscrew pump shaft coupling
assembly (15) from motor shaft. This is a left hand
thread. Remove four motor mounting bolts (19), sep-
arate the motor from frame by withdrawing it straight
back.
• Motor may have to be pried with two screwdrivers if
the shaft seal sticks. The shaft seal stationary seat may
be pushed out of adapter from the motor side. There
is a rubber coupling o-ring (21) between motor shaft
and coupling which will usually remain on the motor
shaft as the seal is pulled over it.
VB SERIES REASSEMBLY
•
Check that the rubber deflector (22) and the coupling
o-ring (21) are on the motor shaft. If they are worn or
damaged, replace. Install stationary seal seat in motor
adapter (18) and mount motor adapter (18) to motor.
Install seal rotating element, making sure faces are
clean and that the last rubber member goes over the
coupling o-ring and onto the motor shaft. Screw the
pump shaft and coupling assembly (15) on until it seats
up against the motor shaft. This is a left hand thread.
Place the spacer (16) into the counterbore on the
motor adapter. Place 2 or 3 shims on top of coupling
to start with, then place diffuser (13), impeller (12) and
bowl (11) over shaft. With a feeler gage check the gap
between the face of the impeller and the stainless bowl.
This gap should be maintained at .020 – .030". Check
this gap as stages are added and shim as required. After
4
all stages are on the shaft, add shims over shaft until
klip ring (10) can be inserted tightly into groove.
•
Check o-ring on both motor adapter (18) and suction
head (1) and replace if damaged. Install bearing spider
(8), adapter ring (9) and screw on casing (3). Note
casing is a left hand thread. Thread on suction head (1).
This is a left hand thread. Torque to 70 ft-lbs.
•
With screwdriver in the slotted end of the pump shaft,
turn the unit over before replacing plug. It should turn
with no resistance except that of the shaft seal.

TROUBLE SHOOTING

FAILURE TO DISCONNECT AND
WARNING
LOCKOUT ELECTRICAL POWER
BEFORE ATTEMPTING ANY
MAINTENANCE CAN CAUSE
SHOCK, BURNS OR DEATH.
Hazardous voltage
can shock, burn or
cause death.
SYMPTOM
MOTOR NOT RUNNING
See Probable Causes 1 thru 5
LITTLE OR NO LIQUID DELIVERED
See Probable Causes 6 thru 13
EXCESSIVE POWER CONSUMPTION
See Probable Causes 3, 13, 14 & 15
EXCESSIVE NOISE & VIBRATION
See Probable Causes 3, 7, 8, 11, 14, 16 & 17
PROBABLE CAUSES
1. Motor thermal protector tripped
2. Open circuit breaker or blown fuse
3. Impeller binding
4. Motor improperly wired
5. Defective motor
6. Liquid in tank below suction
7. Pump is not primed, air or gases in pumpage
8. Discharge, suction plugged or valve closed
9. Incorrect rotation (3 phase only)
10. Low voltage or phase loss
11. Impeller worn or plugged with debris
12. System head too high
13. Incorrect impeller diameter
14. Discharge head too low — excessive flow rate
15. Fluid viscosity and/or specific gravity too high
16. Worn bearing
17. Pump, motor or piping loose