Xylem GOULDS AC8743, Инструкция по эксплуатации

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DISMANTLING THE PUMP
(when removing the rotating element of the pump
is required)
WARNING: Unexpected Startup Hazard
Disconnect and lockout power before servicing.
Failure to follow these instructions could result in
serious personal injury or death, or property
damage
.
CAUTION: Extreme Temperature Hazard
Allow pump temperatures to reach acceptable
levels before proceeding. Open the drain valve.
Do not proceed until liquid stops coming out of the
drain valve. If liquid does not stop flowing from the
drain valve, isolation valves are not sealing and
should be repaired before proceeding. After liquid
stops flowing from drain valve, leave the valve
open and continue. Remove the drain plug located
on the bottom of the pump housing. Do not
reinstall the plug or close the drain valve until
reassembly is completed.
Failure to follow these instructions could result in
moderate personal injury or property damage.
1. Close valves on suction and discharge sides
of pump. If no valves have been installed, it
will be necessary to drain the system.
2. Remove the coupler guard. For spacer
couplers, loosen the capscrews which secure
the coupler flanges to the coupler hubs.
Remove the coupler flanges and sleeve by
compressing the flanges and pulling out from
beneath the hubs or by loosening the Allen set
screws and sliding the hubs back on the
shafts. Remove the coupler hub from the
pump shaft. For non-spacer couplers, loosen
Allen set screws and slide flanges back on
shafts and remove rubber element.
3. Remove all casing main joint capscrews and
dowel pins.
4. Tighten the jacking screws in the upper half of
the casing to separate the upper and lower
casing halves. Then lift off the upper half of
the casing.
5. Tap the stuffing boxes with a soft-headed
hammer to break the seal between the stuffing
box and lower casing half, and lift the rotating
element out of the lower casing. Rotating
element may be removed to a suitable
location for repair.
NOTE: A spare rotating element can be installed
at this point. See Figure 21.
6. Remove the capscrews from each of the
bearing housings and remove the bearing
housings by placing two capscrews in the
jackscrew holes provided.
7. Bend back the lockwasher tab and remove
both the lockwasher and locknut from the
outboard end of the shaft (the opposite side of
the coupling).
8. Remove the capscrews holding gland plate to
the stuffing box.
9. Insert threaded rods into the tapped holes in
the gland plate and install a fixture on the
threaded rods to use as a puller. See Figure
14 for dimensions of Universal Fixture. Using
the puller, tighten the bolt in the center of the
fixture to remove the bearing and gland plate
from the shaft. If the bearing does not come
off the shaft, insert a spacer between the
center bolt and the shaft, and retighten the
bolt. Remove the inboard bearing and gland
plate in the same manner. See Figures 15 and
16.
NOTE:
The locknut and lockwasher are not used
on the inboard bearing.
10. Remove the gland plates from the stuffing
boxes and remove the O-rings from the
stuffing boxes.
CAUTION: Do not reuse the ball
bearings.
11. Remove the mechanical seal head from the
pump shaft.
12. Drive the lip-seals, the mechanical seal seats,
from each of the gland plates by tapping on
them from the rear.
13. Remove the O-rings from each of the gland
plates.
14. Remove the two casing rings from the impeller
and remove the O-rings from each of the
casing rings.
15. Remove the impeller-retaining ring with
retaining pliers. See Figure 22. Heat the
impeller hub on both ends to 350°F maximum,
and pull or push the impeller from the shaft.
25
(Instead of heating the impeller, you may
press impeller off the shaft, if press is
available.)
NOTE: Press away from the coupling end.
NOTE: For impellers with replaceable rings;
remove the rings, if necessary, by cutting with a
cold chisel.
16. Remove the impeller key from the shaft.
Figure 21: Rotating Element
Figure 22: Removing Impeller Retaining Ring
Figure 23: Trimming Casing Gasket
REASSEMBLING THE PUMP
(when removing the rotating element of the pump
is required)
NOTE:
All bearings, O-rings, lip-seals, mechanical
seals, gaskets, impeller rings, and casing rings
should be replaced with the new parts during
assembly. All reusable parts should be cleaned of
all foreign matter before reassembling. The main
casing joint gasket can be made using the upper
and lower half as a template. Lay the gasket
material on the casing joint. Trim the gasket by
lightly tapping with a ball peen hammer so that it is
flush with the inside edges of the casing. See
Figure 23. Do not hit casing edge with hammer
hard enough to round edge.
NOTE: Precut-casing gaskets can be ordered to
minimize the amount of trimming.
1. Before assembling the rotating element
prepare the casing and install the casing
gaskets to the parting line.
2. Clean the gasket surfaces of the casing. Apply
Scotch 3M-77 spray adhesive or equivalent to
the lower half of the casing.
3. Within one minute of spraying, set the
untrimmed gaskets in place on the lower half
of the casing, align the holes in the gaskets
with the holes in the casing, and press the
gaskets firmly against the lower half of the
casing face in the area coated by the
adhesive.
4. Trim the gaskets flush with the lower casing
bores. See Figure 23.
CAUTION
Machined-casing bores must remain sharp at the
casing parting line. Gaskets must be flush with the
bore in order to contact O-rings. Leakage can
result around the stuffing box O-ring if this step is
not properly followed.
5. Assemble the impeller key in the shaft key
slot.
NOTE: For impeller with replaceable rings, heat
each new ring (approximately 300°F-400°F for
bronze) and slide onto the impeller. Using gloves,
hold rings against the impeller shoulder until cool.
6. Check the impeller and casing to determine
the correct relationship. Heat the impeller
evenly to 300°F maximum to expand the bore.