Flowserve MF - Manual (Page 42)

MF USER INSTRUCTIONS ENGLISH 71569191 12/04
Page 42 of 50
®
Check the position of the bearing on the shaft with a
feeler gauge to ensure it is pressing firmly against the
shaft shoulder.
The entire rotating element (bearing frame, stuffing
box head, and impeller) should be assembled before
the bearing endplay is set. The assembly weight is
necessary to properly set the bearing endplay.
a) Mount a dial indicator on the thrust end of the
housing with its arm resting on top of the pump
shaft.
b) With the bearing assembly supported vertically
on the impeller, oscillate the frame to allow the
line bearing rollers to fully seat. If this is not done
false readings will be obtained. Record the dial
indicator reading.
c) Now lift the bearing frame and oscillate the shaft
to allow the thrust bearing rollers to fully seat.
Record the dial indicator reading.
d) The bearing endplay is the difference in readings
in items (b) and (c) above. Repeat (b) and (c)
above to assure measurement consistency.
e) Once the endplay is set, bend over the closest
lock washer tab into one of the thrust bearing
locknut slots. This will secure the bearing locknut
in place.
6.8 Examination of parts
Used parts must be inspected before
assembly to ensure the pump will subsequently run
properly. In particular, fault diagnosis is essential to
enhance pump and plant reliability.
6.8.1 Casing, seal housing and impeller
a) Inspect for excessive wear, pitting, corrosion,
erosion or damage and any sealing surface
irregularities.
b) Replace as necessary.
6.8.2 Shaft and sleeve (if fitted)
Replace if grooved, pitted or worn.
6.8.3 Gaskets and O-rings
After dismantling, discard and replace.
6.8.4 Bearings
a) It is recommended that bearings are not re-used
after any removal from the shaft.
b) The plain liquid lubricated bearings may be re-
used if both the bearing bush and bearing sleeve
show no sign of wear, grooving or corrosion
attack. (It is recommended that both the bush
and sleeve are replaced at the same time.)
6.8.5 Bearing isolators, labyrinths or lip seals
(if fitted)
a) The lubricant, bearings and bearing housing
seals are to be inspected for contamination and
damage. If oil bath lubrication is utilized, these
provide useful information on operating
conditions within the bearing housing.
b) If bearing damage is not due to normal wear and
the lubricant contains adverse contaminants, the
cause should be corrected before the pump is
returned to service.
c) Labyrinth seals and bearing isolators should be
inspected for damage but are normally non-
wearing parts and can be re-used.
d) Bearing seals are not totally leak free devices.
Oil from these may cause staining adjacent to the
bearings.
6.9 Assembly
To assemble the pump consult the sectional
drawings, see Section 8, Parts list and drawings .
Ensure threads, gasket and O-ring mating faces are
clean. Apply thread sealant to sealing pipe thread
fittings.
Torque all bolts per torque specifications listed in
section 6.5
6.9.1 Assembly of bearing frames 3A, 4A and 5A
a) For oil lubricated frames install oil slingers and oil
ring collar on the shaft.
b) Be sure the shoulders where bearings seat are
free of burrs and contaminants.
c) Mount bearings on shaft. Note that the line
bearing can face either way. However, the thrust
bearing must have the retaining ring on coupling
end. See "Maintenance of Bearings".
d) Install bearing lock-washer and thread on bearing
locknut snug. Press together the tab and slot
which line up.
e) Pack each bearing with grease only if the pump is
grease lubricated.
f) Install shaft and bearing assembly in bearing
housing from coupling end until the thrust bearing
retaining ring contacts the edge of the housing.
g) Install line and thrust bearing lip seals into their
respective covers and grease their lips. Be sure
the thrust bearing cover seal ring is properly
seated in its groove.
h) Install line and thrust bearing covers. For oil
lubricated frames be sure that line bearing cover
gasket does not cover oil drain hole.
i) Install deflector.