Flowserve Durco Mark 3 ISO Frame Mounted - Manual (Page 31)

DURCO MARK 3 ISO FRAME MOUNTED ENGLISH 85392719 12-14
Page 31 of 52
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6.9.3 Gaskets, O-rings and V-ring when fitted
After dismantling, discard and replace.
6.9.4
Bearings
It is recommended that bearings are not re-used after
any removal from the shaft.
6.9.5
Bearing labyrinths/isolators
Labyrinth seals and bearing isolators should be
inspected for damage but are normally non-wearing
parts and can be re-used.
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. 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.
Bearing seals are not totally leak free devices. Oil from
these may cause staining adjacent to the bearings.
6.9.6
Bearing housing and carrier
Inspect the bearing carrier circlip groove. Ensure it is
free from damage and that housing lubrication
passages are clear. Replace grease nipples or the filter
breather (where fitted) if damaged or clogged. On oil
lubricated versions, the oil level sight glass should be
replaced if oil stained.
6.10 Assembly
To assemble the pump consult the sectional drawings.
See section 8, Parts lists and drawings.
Ensure threads, gasket and O-ring mating faces are
clean. Apply thread sealant to non-face-sealing pipe
thread fittings.
6.10.1
Bearing housing and rotating element
assembly
a)
Clean the inside of the bearing housing [3200],
bearing carrier [3240] and bores for bearings.
b) Attach bearing housing support foot [3134].
c) Fit the thrust ball bearing [3013] on to shaft [2100].
The double row thrust bearing must not
have a filling slot, as such bearings are limited to
taking thrust in only one direction. If the pair of
angular contact thrust bearings are to be fitted,
these must be mounted back-to-back, as shown
below:
Grease
retainer
[3864]
Grease retainer (clearance type) is only
fitted on grease lubricated units
The following methods are recommended for fitting
the bearings onto the shaft:
Method 1: Use a hotplate, hot bath, oven or
induction heater to heat the bearing race so it can
easily be placed in position then allowed to shrink
and grip the shaft. It is important that the
temperature is not raised above 100 ºC (212 ºF).
Method 2: Press the bearing onto the shaft using
equipment that can provide a steady, even load to
the inner race. Take care to avoid damaging the
bearing and shaft.
d) With bearings at ambient temperature, screw on the
self-locking bearing locknut [3712.1] (with its
polyamide insert facing away from the bearing) until
tight.
e) With the double row thrust bearing place the
bearing circlip [6544] over the shaft, with the
tapered face facing the impeller end.
f) With the heavy duty thrust bearing option, the lock nut
[3712.2], [3864] grease retainer and [3712.2] if grease
lubricated, should be placed on the shaft with the
larger diameter end facing the impeller end.
g) Fit pump radial ball bearing [3011] onto the shaft
using Method 1 or 2 above.
h) With the NUP roller bearing option, the loose ring
should be against the shaft shoulder.
i) Fit O-ring [4610.2] on the bearing carrier. Lightly
lubricate the bearing carrier bore and O-ring.
j) Ensure the shaft keyway edges are free of burrs.
During installation, use shimming or tape over the
keyway to avoid damaging the drive side bearing
seals.
k) On grease lubricated pumps, ¾ fill the space between
bearing races with the appropriate grease.
l) Slide the bearing carrier [3240] onto the shaft/bearing
assembly and insert inner circlip [6544] into the carrier
groove or screw up the bearing locking ring.
m) Check shaft [2100] for free rotation.
n) Fit the labyrinth ring [4330] into the bearing housing
[3200] ensuring the drain hole faces the bearing
and is at the 6 o'clock position.