Xylem A-C Fire Pump – Vertical Turbine Fire Pump AC8499 - Manual (Page 13)

13
Installing the Discharge Head
OPEN LINESHAFT
1. A-C Fire Pumps are provided with either a cast iron or fab
steel type head. Install the discharge head as follows:
2. If the stuffing box is assembled to the head, remove it and
all attached piping. See Figure 5 for the stuffing box pro-
vided for the A-C Fire Pump being assembled.
3. Remove coupling guard if provided. Attach a sling through
windows (hand holes) or thread two eyebolts in the head
driver support mounting holes diametrically opposite and
hoist discharge head over the protruding headshaft.
4. Orient the discharge head in the required position and
lower the head, centering the vertical hole with the head-
shaft or stub 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 the column. Rotate the dis-
charge head, screwing it onto the column, butting the top
of the column tightly against the discharge head.
5. For flanged column, continue to lower the discharge head
until the discharge head engages the column. Install cap-
screws and secure discharge head to the column flange.
Tighten capscrews gradually in diametrically opposite
pairs.
6. Lift pump assembly high enough to allow rotation of the
supports. Realign and lower assembly. Install and tighten
remaining capscrews. Repeat rotation and tightening pro-
cedure, until all capscrews are uniformly tight.
7. Using a device with the capacity to support the weight of
the entire pump assembly, hoist bowl, column, and head
assembly and remove supports.
NOTE
: Eyebolts or 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 dis-
charge head to mounting plate. Check the levelness of the
discharge head in all directions, utilizing a spirit level
across the driver mounting surface of the discharge head.
Stuffing Box Installation
Assemble stuffing box in accordance with Figure 5, below.
STANDARD CONSTRUCTION
1. Position gasket on discharge head. Slide stuffing box
(616) down over shaft and into position on the gasket.
Secure stuffing box with capscrews.
2. Insert lantern ring (621) into stuffing box. Be sure it is prop-
erly positioned so that it aligns with the lubrication passage
in the stuffing box.
3. Grease the packing rings (620) for easier installation.
4. 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 five (5) rings in this manner. Stagger
ring joints 90º apart. The split gland may be used as a tam-
per for the top ring.
5. Install the split gland and threaded nuts on the split gland
studs. Tighten nuts then relieve the nuts and tighten finger
tight. Attach bypass line to tube fitting in the stuffing box.
6. Final adjustment of the stuffing box must be made at pump
start up. This final adjustment applies to all stuffing box
styles.
7. A properly packed stuffing box should be loose enough to
allow the shaft to be turned manually.
Figure 5
CAUTION:
Do not bend or scrape the shaft protruding
above the column. This could result in bending or
damaging the shaft.
CAUTION: Check that the split gland is square in
the stuffing box. Cocking can cause uneven compres-
sion of packing and damage to the shaft or sleeve.
CAUTION: Do not overtighten packing or excessive
wear can occur on the shaft or sleeve.