Flowserve WPG IDP - Manual (Page 22)

WPG and WPH USER INSTRUCTIONS ENGLISH 26999969 10-12
Page 22 of 40
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6.8.5 Bearing isolators, labyrinths or lip seals (if
fitted)
The lubricant, bearings and bearing housing seals
are to be inspected for contamination and damage. If
oil bath lubrication is utilised, 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.
If the pump is fitted with lip seals they should be
replaced at overhaul.
Labyrinth seals and bearing isolators should be
inspected for damage but are normally non-wearing
parts and can be re-used.
Bearing seals are not totally leak free devices. Oil from
these may cause staining adjacent to the bearings.
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.
6.9 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.
6.9.1 Bearing housing and rotating element
assembly
a)
Clean the inside of the bearing housing, bearing
carrier and bores for bearings.
b) Attach bearing housing support foot.
c) Press drive side bearing(s) on to shaft. If duplex
bearings are to be fitted, these must be mounted
back-to-back, as shown below:
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°C (212°F).
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 damage to the bearing
and shaft.
a)
Fit bearing locknut (and lockwasher where
applicable).
b) On grease lubricated pumps, pack the bearings
with grease and pack the bearing cover cavity
approximately one third full with grease.
c) Insert the shaft, complete with bearings, into the
bearing housing/frame towards the pump end.
d) When fitting a labyrinth flinger, the groove in the
pump end bearing cover should be filled with
grease and the labyrinth flinger positioned to give
a clearance of 0.5 to 0.65 mm in front of the
bearing cover. Screws for the drive end bearing
cover should be tightened uniformly to 6.8 Nm
(5 lbf
•ft).
e) Refit the liquid thrower.
f) Fit the shaft sleeve (if applicable) ensuring the
O-seal ring is correctly fitted.
6.9.2 Packed gland units
a) The stuffing box should be packed with good quality
packing suitable for the liquid being handled.
b) Assemble the gland packing into the stuffing box
housing before fitting on to the shaft.
c) Stagger the joints in the gland packing by 90
degrees to each other.
d) The lantern ring halves (if required) should be
positioned mid-way along the packing.
e) Position the gland squarely against the last ring
and tighten the gland nuts finger-tight only.
f) Install into bearing housing assembly and fit the
two screws to hold the seal housing in place.
g) Check that the shaft rotates freely.
6.9.3 Seal housing and seal assembly
a)
Extreme cleanliness is required. The sealing
faces and shaft or sleeve surface must be free
from scratches or other damage.
b) Carefully press the stationary seat into the
mechanical seal housing or cover, ensuring that
the seating ring is not deformed.
c) Where an anti-rotation pin is fitted ensure that
correct engagement with the slot is achieved.
d) Place any separate seal covers over the shaft.