Goulds Pumps 3408A - IOM - Manual (Page 39)

DISASSEMBLY & REASSEMBLY
DISMANTLING THE PUMP
(when removing the rotating element of the pump is
required)
s
! WARNING
Unexpected Startup Hazard
Disconnect and lockout power before servicing.
Failure to follow these instructions could result in seri-
ous 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. (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.
3408A IOM 6/08
31
4