SPP Pumps Thrustream - Extended - Manual (Page 17)

Operators Instructions for Horizontal
Extended Thrustream Centrifugal Pumps
Manual No/Rev
W12-005E / 3
Our policy is one of continuous improvement and we reserve the right to alter specifications at any time
Page 15 of 28
Removal of the Rotating Assembly Procedure
1. Remove the remaining screws (62A) that
retain the bearing housings (62) to the bottom
half casing (B1).
2. Tap the inserts (41/53) with a soft-faced
hammer to break the seal between the insert
and the bottom half casing (B1).
3. Lift the rotating assembly clear of the bottom
half casing and support the shaft on suitable V
blocks with the impeller clear of the work
surface.
4 If necessary, remove the case wear ring
dowels (23A) from the bottom half casing
(B1).
5 With feeler gauges, check the clearance
between the case wear rings (23) and the
impellers (21), compare clearance with the
figures below.
Internal
Clearances
Diametral
mm
Radial
mm
Min Max Min Max
TR20A, TL30A, TT25A,
TP15T & TR20T
0.440 0.651 0.220 0.325
TN25A, TQ25A, TR30A
& TM35A
0.440 0.659 0.220 0.330
TP30A, TV30A, TN35A
& TQ35A
0.460 0.689 0.230 0.345
TT35A 0.460 0.549 0.230 0.275
Note Increase in the wear ring clearance allows
increased internal leakage with resultant loss
of pump performance, head and efficiency.
When the clearance is double the original
clearance, it is recommended that new wear
rings are fitted. It is permissible to run the
pump with increased clearance due to wear
but the loss of pump efficiency will significantly
increase the pump running costs.
Procedure to Dismantle the Rotating Assembly
1. Remove the screws (64A) and slide the
bearing cap (64) along the shaft towards the
liquid thrower (72).
2. Remove the screws (53A) to free the bearing
housing (52) for removal.
3. Using a suitable puller, withdraw the drive end
bearing housing from the shaft (71).
4. Remove the cover plate (62Y) from the non-
drive end bearing housing and using a suitable
puller, withdraw the non-drive end bearing
housing from the shaft (71).
5. Using a suitable punch, flatten the lock washer
(75F) and remove the bearing locknut (75)
and the lock washer.
6. Using a suitable bearing puller on the inner
race of each bearing, pull the bearings (66 &
67) off the shaft.
7. Release the screws (72A) and remove the
liquid throwers (72) from the shaft.
8. For pumps fitted with mechanical seals: Slide
the mechanical seal assemblies off the shaft
(71), remove the inserts (53) complete with
throttle bush (45) and set aside for inspection.
9. For pumps fitted with soft packed glands:
Slide the gland (50) off the end of the shaft
(71) and remove the inserts (53) complete
with packing rings (51) and lantern rings (46)
and set aside for inspection.
10. If not already removed, remove the case wear
rings (23) and set aside for inspection and
measurement.
For Clockwise pump construction:
11. Using a suitable ‘C’ spanner, unscrew and
remove the non-drive end sleeve (B47) on a
soft packed pump or impeller nut (A21) when
a mechanical seal is fitted.
For Counter Clockwise pump construction:
12. Using a suitable ‘C’ spanner, unscrew and
remove the drive end sleeve (A47) on a soft
packed pump or impeller nut (B21) when a
mechanical seal is fitted.
Note Light tapping with a soft faced mallet may be
needed to free the impeller from the shaft, do
not damage the impeller if it is to be reused.
13. Using suitable pullers or levers, slide the
impeller (21) of the shaft (71).
14. Scribe a line on the shaft to mark the position
of the locked sleeve or nut for reassembly.
15. Withdraw the impeller key (116) and unscrew
and remove the remaining sleeve or the
impeller nut.
Cleaning and Inspection of Parts
1. Clean the bearings thoroughly with an
approved cleaning fluid, kerosene or white
spirit.
2. Dry the bearings with dry compressed air or
with a clean soft cloth by hand and by spinning
by hand. Confirm that the bearings rotate
smoothly without slackness.