Xylem 8100 Series Centrifugal Pumps AC2515 REV.C - Manual (Page 48)

FIGURE 50 – UPPER CASING HALF REMOVED
CAUTION:
Do not cut or damage O-ring 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.
27. 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.
NOTE: Torque values are essential in
obtaining proper gasket compression so no
leakage can occur at main joint.
28. Rotate the shaft by hand to assure that it
turns smoothly and is free from rubbing or
binding.
29. Install seal water piping (0-952-0).
ADJUSTABLE WEAR RINGS
Adjustable rings are an assembly of two threaded
rings. The outer, stationary ring is held in the
casing by a tongue and groove and an anti-
rotation pin in the lower half main joint. The inner,
adjustable ring can be moved axially, in either
direction, by rotating it. The ring is held in position
by a stainless steel locking pin. All rings have
clockwise threads.
Adjustment
When the clearance between the impeller
wear face and the adjustable wearing ring
becomes excessive; i.e., approximately .020"
to .030", remove the upper half casing and
pull the locking pin.
Rotate the inner rings clockwise to restore
.005"-.008" clearance greater than shaft end
float between the ring and the impeller. Drill a
new hole in the inner ring for the locking pin.
This is a blind hole – do not drill through.
Replace the locking pin and upper half
casing.
(3-009-9)
SLEEVE
FIGURE 51 – ADJUSTABLE WEAR RINGS
Disassembly and Reassembly
Adjustable rings are removed in the same
manner as standard casing rings. They can
be separated for cleaning. Adjustable rings
are installed in the pump with stationary and
the adjustable members assembled but not
pinned. Turn the adjustable member
counterclockwise to provide maximum
impeller clearance and slide over shaft ends.
With the rotating element in pump, the rings
can be adjusted. Be sure that stationary
member has its flange flush against casing
lower half.
Move rotating element toward outboard end
as far as bearings permit. Screw outboard
end adjustable ring toward impeller to obtain
.005"-.008" axial impeller clearance. Drill
through stationary ring hole into adjustable
ring and insert locking pin. Move rotating
element toward coupling and set coupling
end ring in the same manner.
OIL LUBRICATED BEARINGS
This section describes how to change the oil for oil
lubricated bearings. Figure 52 shows a typical oiler
assembly.
(3-570-3)
STATIONARY RING
(3-571-3)
ADJUSTABLE RING
LOCKING PIN
(3-943-9)
CASING
(2-001-0)
IMPELLER
(4-002-0)
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