Xylem 8100 Series Centrifugal Pumps AC2515 REV.C - Manual (Page 37)

26. PACKING (NON ASBESTOS)
Install 12 full rings of packing (6 per
stuffing box) so that the ends butt, leaving
no gap between the packing and the
stuffing box. (Refer to the table in Figure
17 for packing size.) Press the packing to
the bottom of the stuffing box. Stagger the
joints of each packing ring at least 90
degrees. For 3 adjacent rings, use the 4, 8
and 12 o’clock positions. NOTE: The last
ring in each box may not be required until
after the pump has operated for a period
of time.
FIGURE 26 – UPPER CASING HALF REMOVED
NOTE: When supplied, the seal cage will replace
the third packing ring from the bottom, requiring
only 10 rings of packing. The seal cage must be
aligned with the seal water inlet when the packing
is compressed.
CAUTION:
Do not cut or damage O-rings when
lowering the rotating element into position. When
all four anti-rotation pins (3-943-9) are correctly
located, there will be some casing ring looseness.
Assemble the glands (1-014-9), washers (0-909-
0), and bolts (1-904-9) square with the stuffing box
and pull up tight. Then loosen the gland bolts (1-
904-0) to permit the packing to expand. Then
retighten finger tight. Final adjustment of the gland
bolts must be done with the pump running. Allow
30 minutes between adjustments. A good
adjustment should allow approximately one (1)
drip per second.
23. Lower the upper half casing (2-001-0) into
place using the tapered dowel pins (2-
916-1) and install casing main joint bolts
(2-904-1). The casing joint bolts should be
tightened to the following torques: 140 ft-lb
minimum for 5/8"-11 hex head cap screws
(Grade 5); 350 ft-lb minimum for 7/8"-9
Ferry Cap Counterbore screws (Grade 8).
Bolt torquing pattern is shown in Figure
59.
OPTIONAL METHOD FOR INSTALLING
PACKING (AFTER PUMP DISASSEMBLY)
NOTE: Torque values are essential in
obtaining proper gasket compression so no
leakage can occur at main joint.
Place stuffing box (3-073-9) on a table or
workbench with the stuffing box opening up.
Assemble the packing per step 26 with the shaft
sleeve placed in the stuffing box. After completing
step 26, remove shaft sleeve and continue to
assemble pump per step 4.
24. Rotate the shaft by hand to assure that it
turns smoothly and is free from rubbing or
binding.
25. Install seal water piping (0-952-0), if
supplied.
The entire assembly may then be placed into
position over the sleeve in step 11.
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