Bell & Gossett VTP2006 Series VTP – Vertical Turbine Pumps - Manual (Page 19)

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interchanging any two leads. (For three phase only.
For single phase motors see motor manufacturer’s
instructions.)
Never check motor rotation with the drive
coupling in place. The bore clearance
between the drive coupling and the pump shaft O. D.
is so close that should the motor spin with this shaft
stationary, galling and locking together is very likely to
take place.
11. Install motor drive coupling. (Be sure to line up the
match mark made at step 6.) Inserting the ratchet
pins if a non-reverse ratchet is used. Match the
coupling lugs with corresponding holes in motor.
Tighten hold down bolts evenly, making sure driver
coupling is properly seated in the register fit.
12. Fit gib key (730) into keyway, by filing if necessary,
to where there is a snug but sliding fit. This key
must be able to be removed by gentle leverage with
a screwdriver under it.
13. Be careful that the gib key (730) is not too high so
as to hold up the adjusting nut (604) from seating
on the drive coupling. If it is, cut off some length of
the key.
14. Install adjusting nut (604) to hand tight.
COMBINATION ENGINE AND MOTOR DRIVES
1. On combination drivers, the motor is invariably on
top with a projecting head shaft extension.
2. Follow all procedures outlined in the previous
paragraph, except that the motor must be lowered
over this extended head shaft and great care must be
taken to center it exactly so as not to bump or miss-
align the shaft while the motor is being lowered into
place.
3. There are several methods of running engines
without electric motors and vise versa, requiring
simple adjustment to the combination drive, but
they are too numerous to mention here and can be
obtained from the gear manufacturers instructions
included with the shipment.
IMPELLER ADJUSTMENT FOR ALL
HOLLOW SHAFT DRIVERS
NOTE: Shaft adjustment up or down is accomplished by
turning the adjusting nut (604) Figure 13.
NOTE: There are five holes in the adjusting nut and only
four in the motor coupling. See Figure 13.
1. With shafting all the way down and the impellers
resting on their seats, turn the adjusting nut (604)
in counter-clockwise direction, thus lifting the shaft,
until the impellers just clear their seats and the
shaft/motor turns free by hand. This removes all
deflection from the shaft.
2. If pump setting is 200 ft. or less, make another two
turns on the adjusting nut for the first 100 ft. (3
turns for 12 thread/inch shaft). Line-up one of the
holes in the adjusting nut with the nearest hole in
CAUTION
the driver coupling. Insert the capscrew in the hole
and tighten it.
NOTE: 1.00” and 1.18” diameter shafts are 12 thread
per inch. All the larger sizes are 10 thread per
inch.
3. For pump setting over 200 ft. see IOM for DWT.
FOR OPEN IMPELLERS
1. With shafting all the way down and the impellers
resting on their seats, turn the adjusting nut (604)
in counter-clockwise direction, thus lifting the shaft,
until the impellers just clear their seats and the
shaft/motor turns free by hand. This removes all
deflection from the shaft.
2. Align hole “A” in the
adjusting nut (604) and
hole “C” in the driver
coupling (See Figure13) or
whatever similar holes are
in like position. If care is
exercised, this will give an
initial impeller clearance
of 0.001” to 0.003”
depending on shaft size or
the pitch of the thread.
3. Insert capscrew into hole
“B” provided these are the
nearest matching holes
for counter-clockwise
rotation of adjusting nut,
turn adjusting nut counter-
clockwise until holes “B”
and “D” line up. This
gives 1/20 of a turn
which is 0.004” on
12 threads per inch
shaft or 0.005” on
10 threads per inch
shaft.
4. Normal impeller
clearance for the open
impeller is consider to be 0.015”
for the first 10 ft of the column
length and 0.010” additional clearance for each
10 ft of length thereafter. This can be reduced in
some instances where is necessary, but should not be
attempted without consulting the factory or factory
serviceman is present.
INSTALLATION OF A SOLID SHAFT DRIVER
NOTE: When pump is supplied with an oil lubricated
thrust pot, do not secure driver to discharge
head until after the thrust pot and flexible
coupling are installed. (See page 22 for thrust
pot installation instruction.)
Do not work under a heavy suspended
object unless there is a positive support
and safe guard which will protect personnel should a
hoist or sling fail.
(604) ADJUSTING NUT
LOWER IMPELLER
RAISE IMPELLER
MOTOR COUPLING
ROTATION
A
B
G
D
H
C
E
F
Figure 13
WARNING