weld from between the ring and the casing before prying out
the ring.
q) If necessary, remove the casing back cover ring (6) by prying it
out of the casing back cover (22). If the ring is tack-welded into
the casing back cover, grind the weld from between the ring
and the casing back cover before prying out the ring.
r) If necessary, press the throat bushing (54) out of the casing
back cover (22), using care to not damage the gland studs (14)
nor the casing back cover (22).
s) I so desired, the bearing housing foot (9) can be removed from
he bottom of the bearing housing (26).
t) Clean and inspect all parts.
REASSEMBLY PROCEDURE
WARNING:
Use only high quality tools.
Wear protective equipment as advised at the beginning of this
section.
Use mechanical lifting equipment to lift assemblies and components.
Do not hammer on any parts. Personal injury and/or damage to
equipment may occur.
Do not attempt to manufacture parts or modify Dean Pump parts in
any manner. Death, personal injury, and/or damage to equipment
may occur. One example of the above would be overboring the
stuffing box or the seal chamber, which removes metal that is
required to contain fluids. Removal of this metal reduces the pres-
sure containing capability of the part and may create a leak path
through the part. If the part separates two different fluids, mixing of
the fluids could cause an explosion. Water leakage into a heat
transfer liquid is one example of an explosive possibility.
Replace all gaskets, seals, bearings, and lubricants. Replace all parts
that have worn, corroded, eroded, or otherwise deteriorated.
Use only Dean Pump Division of Met-Pro Corporation parts.
To reassemble the pump, perform the following steps:
a) Clean all parts thoroughly.
b) If needed, press a new throat bushing (54) carefully into the casing
backcover (22).
c) If needed, press a new casing backcover ring (6) into the casing
backcover (22).
d) If needed, press a new casing ring (6A) into the casing (5).
e) If the bearing housing foot (9) was removed, bolt it back to the
bearing housing (26). Be sure that the dowel pins are in place
between the foot (9) and the housing (26). Tighten the cap-
screws to 50 ft. lb.
f) If the bull’s eye sight glass was removed, apply pipe sealant to
the threads of a new bull’s eye sight glass and tighten it into the
side of the bearing housing (26). Torque to 50 ft. lb.
g) If the bearing housing vent (80) was removed, install a new
vent (80), without thread sealant, into the top of the bearing
housing (26). Tighten to 20 ft. lb.
h) Install new “O” rings onto the O.D. and into the I.D. of both the
labyrinth seals (76 and 76A). Lubricate the “O” rings on the
O.D. of both labyrinths.
i) Press the front labyrinth seal (76) into the seal ring (27).
j) Press the rear labyrinth seal (76A) into the bearing end cover
(28). The “expulsion port” (the slot in the O.D.) of the labyrinth
(76A) must be positioned at the bottom of the end cover. This
will be inline with the machined “oil return” slot in the end
cover (28).
k) Press the bearings (25 and 25A) onto the pump shaft (29).
Press only on the inner races of the bearings. Do not press on
the outer races. The thrust bearing is a matched pair of angular
contact bearings and must be assembled “back to back”. See
the illustration on page 15. Be sure to place the snap ring (75B)
over the shaft before pressing on the last bearing(s).
I) Place a new bearing lock washer (31A) onto the pump shaft
(29). Tighten the bearing lock nut (31) against the lock washer,
to 75 ft. lb., while holding the shaft (29) against rotation with a
hook spanner wrench in the keyway. Another way to keep the
shaft from turning is to place the coupling hub onto the shaft
and hold it with a wrench. Bend one of the tabs of the lock-
washer (31A) into the corresponding slot in the locknut (31).
m) Lubricate the O.D. of the bearings (25 and 25A) and the bores
of the bearing housing (26). Slide the shaft (29) bearing (25
and 25A) assembly into the rear of the bearing housing (26).
After the radial bearing (25) has passed through the rear bore
of the housing, reach into the opening, with snap ring pliers,
and place the retaining ring (75B) into the rear bore of the
housing. Install the retaining ring with the opening in the ring at
the bottom of the housing so that it is centered with the oil return
groove in the housing. The ring does not have to be in it’s
groove. The bearing housing is machined with a long chamfer
that allows the thrust bearing (25A) to push the ring into it’s
groove as the shaft assembly is pushed into the bearing hous-
ing. The shaft may now be fully inserted until the thrust bearing
(25A) is firmly against the retaining ring (75B), and the retain-
ing ring is firmly in it’s groove.
n) Lubricate the end cover gasket (77B), which is an “O” ring.
Place the end cover gasket (77B) onto the end cover (28).
Lubricate the I.D. of the rear labyrinth seal (76A), which is in the
end cover (28). Lubricate the area of the pump shaft (29), just
behind the thrust bearing (25A), where the rear labyrinth seal
(76A) will be mounted. Slide the bearing end cover (28), labyrinth
seal (76A) assembly carefully over the end of the pump shaft (29).
Be careful that the “O” ring in the I.D. of the labyrinth seal (76A)
does not contact the keyway of the shaft (29) and become dam-
aged. Placing a piece of plastic electrical tape over the keyway,
before this assembly operation, will give a measure of protection.
Rotate the end cover (28) so that the machined “oil return slot” is
towards the bottom of the bearing housing (26). Seat the end
cover fully into the bearing housing and tighten the end cover bolts
to 25 ft. lb.
o) Re-install the bearing housing oil cooler (109) into the bearing
housing (26). Install the oil cooler (109) into the open 1” NPT con-
nection and carefully guide the end of the tubing through the tub-
ing connector on the opposite side of the bearing housing (26).
Apply pipe sealant to the 1” male pipe threads, and tighten the 1”
tube connector into the bearing housing (26) with a torque of 50
ft. lb. The ferrules used in these tube connectors are plastic, to
enable disassembly and re-assembly without damaging the cooling
tube. When tightening these connectors, tighten to only 5 ft. lb.
p) Lubricate the I.D. of the front labyrinth seal (76), which is in the
seal ring (27). Lubricate the area of the pump shaft (29), just in
front of the radial bearing (25), where the front labyrinth seal (76)
will be mounted. Slide the seal ring (27), labyrinth seal (76) assem-
bly carefully over the end of the pump shaft (29). Be careful that
the “O” ring in the I.D. of the labyrinth seal (76) does not contact
the keyways of the shaft (29) and become damaged. Press the
seal ring (27), labyrinth seal (76) assembly into the front of the
bearing housing (26). The “expulsion port” (the slot in the O.D.) of
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