Xylem IMVIT R01 Model VIT Vertical Industrial Turbine Pumps - Manual (Page 15)

15
15. Install the top shaft or stub shaft and coupling.
Do not drop any foreign object into the
bowl assembly. Such an object can cause
serious damage to the pump and any downstream
components. Any foreign object dropped into the bowl
assembly must be retrieved prior to continuing assembly.
INSTALLING THE DISCHARGE HEAD
VIT Pumps are provided with either a cast iron or
fabricated steel type head. For pump with below
ground discharge, a motor stand is provided instead the
discharge head. Install the discharge head as follows:
1. If the stuffing box (See Fig. 9) or tension nut (See
Fig. 10) is assembled to the head, remove it and all
the attached piping.
2. For threaded column, check to be sure that the
column flange (637) is securely attached to the
bottom of the discharge head. Check and tighten
the capscrews (or socket head screw) gradually in
diametrically opposite pairs.
3. Remove coupling guard if provided. Attach a sling
to the lifting lugs on the side of the discharge head
through windows and hoist discharge head over the
protruding top shaft (or stub shaft).
Do not bump or scrape the shaft protrud-
ing above the column. This could result in
bending or damaging the shaft.
4. Orient the discharge head in the required position
and lower the head. Center the vertical hole with
the top shaft protruding above the column. For
threaded column, continue to lower the discharge
head until the large threaded hole in the bottom
of the discharge head rests squarely on top of
column. Clean the threads at upper end of column
assembly and lubricate with thread compound.
Rotate discharge head, screw it onto the column,
for short set-pump, (without the column adjusting
nipple) butting the top of column tightly against the
discharge head.
5. For flanged column, continue to lower the discharge
head until the discharge head engages the column
flange. Install capscrews and secure discharge head
to the column flange. Tighten capscrews gradually
in diametrically opposite pairs. Lift the pump
assembly high enough to allow rotation of the
supports. Realign and lower assembly. Install and
tighten remaining capscrews. Repeat the rotating
and the tightening procedure until all capscrews are
uniformly tight.
6. Hoist the discharge head by lifting lug and remove
the elevator clamp attached to column.
7. Remove the support timbers or I-beams and clean
the top of foundation or base plate. Orient the
discharge head in the required position.
NOTE: Sling should be rated to handle in excess of the
pump weight.
8. Lower bowl, column and head assembly, until
discharge head mounting flange engages base plate.
Secure discharge head to the foundation or base
plate. Check the levelness of the discharge head in
all directions, utilizing a machinist level across the
driver’s mounting surface of the discharge head.
9. Check whether the top shaft (or stub shaft) is in the
center of the stuffing box bore. If not, the shaft must
be centered by shimming the head base and the sub
base (or the foundation).
10. Rotate the shaft approximately 90º. Check again
whether the shaft is at the center of the stuffing box
bore or not. If not, either the top shaft is bent or the
first shaft below it did not butt properly. Correction
must be made before the installation procedures can
proceed.
INSTALLING THE STUFFING BOX
Assemble stuffing box as shown in Figure 9.
1. Clean the surface of the discharge head where
the stuffing box will be mounted and remove
any nicks or burrs with a fine flat file. Position
gasket on surface. Slide stuffing box (616) down
over headshaft and into position on the gasket.
Secure stuffing box with capscrews. Make sure
the capscrews are torqued equally to prevent
misalignment.
2. Grease the packing ring (620) for easier installation.
3. Twist the packing ring sideways to get it around the
shaft easily. Start the first ring into the stuffing box.
When the entire ring is worked in using the fingers,
tamp it down using a split wood bushing (or equal)
and push the packing ring down firmly. It must seal
on the shaft and bore of the stuffing box. Install all
three (3) rings in this manner. Stagger ring joints 90º
apart. The split gland may be used as a tamper for
the top ring.
4. Insert lantern ring (622) into stuffing box. Be sure
it is properly positioned so that it aligns with the
lubrication passage in the stuffing box.
5. Insert three (3) additional rings of packing. Stagger
ring joint 90º apart.
6. Install the split gland and screw nuts on the split
gland studs. Tighten nuts then relieve the nuts and
tighten finger tight.
Check that the split gland is square in the
stuffing box. Cocking can cause uneven
compression of packing and damage to the shaft or sleeve
and heat up the shaft and stuffing box.
CAUTION
CAUTION
CAUTION
Figure 9
(619) STUD (2)
(735) HEX NUT
(2)
PORT “A”
(624) BYPASS LINE
(618) GLAND
PORT “B”
(621) O-RING
(620) PACKING
(6 RING)
(616) STUFFING
BOX
(617) BEARING
(622) LANTERN
RING