SPP Pumps Thrustream - Extended - Manual (Page 16)

Manual No/Rev
W12-005E / 3
Operators Instructions for Horizontal
Extended Thrustream Centrifugal Pumps
Our policy is one of continuous improvement and we reserve the right to alter specifications at any time
Page 14 of 28
and lift the tab of the lock washer.
7. Fit the bearing housing as per the drive end
bearing replacement procedure, paragraphs
17 to 20.
8. Refit the cover plate (62Y).
6.6 Mechanical Seal Replacement
Mechanical seals will need replacement when
failure has occurred, they may not be replaced
without removal of the rotating assembly
unless the motor is demounted and the
coupling is removed from the pump shaft.
It is recommended that new mechanical seals
are fitted when conducting a full pump strip-
down for overhaul to give maximum operating
life.
Refer to the seal manufacturer’s instructions
in Appendix III and lock the seal before
removing the retaining nuts (52A) and sliding
the seals back from the face of the insert
(A/B53).
Mechanical Seal Replacement Procedure
1 Isolate the pump and drain the casing using
the air vent valves (308) and drain plugs (1P &
1M) provided.
2 Disconnect the seal flush pipe, remove the
four hexagon screws (52A) that retain the
mechanical seal, and slide the seal assembly
off the shaft.
3 Proceed as per the bearing replacement
instructions, paragraphs 1 to 10.
4 Remove the nuts (52F) from the studs (52A)
and withdraw the mechanical seal (52) from
the shaft (71).
5 Fit a new mechanical seal as per the
manufacturer’s instructions in Appendix III
6 Reconnect the seal flush pipe.
7 Proceed as per the bearing replacement
instructions, paragraphs 11 to 21.
6.7 Pump Overhaul and Repairs
Refer to a certified Pump Section drawing or
the typical cross section drawing in Section 8.
Note the hazards outlined in Section 6.
Impeller Inspection Procedure
1 Isolate the pump and drain the casing using
the air vent valves (308) and drain plug (1M)
provided.
2 Remove the seal lubrication pipes (A107) from
the inserts (53) for soft packed pumps or from
the mechanical seal (52).
3 Remove the screws (62A) that retain the
bearing housings (62) to the top half casing
(A1).
4 Remove the nuts (1F) from the casing studs
(1B) securing the top half casing (A1) to the
bottom half casing (B1).
5 Press or tap out the dowels (1C).
6 Using a pair of pry bars in the slots provided
between the top and bottom casings, apply
pressure to break the gasket seal and lift the
top half casing (1A) off the bottom half casing
(1B).
7 If the top half casing is trapped between the
bearing housings, release the remaining
screws (62A) from the non-drive-end bearing
housing (62) and back it off by about 1mm.
5 Using the eyebolt and a suitable lifting device,
lift the top half casing (A1) clear of the
impeller, place to one side on a clean flat
surface.
6 At this stage, the impeller may be inspected
for damage or blocking and cleaning if
necessary.
To check the pump shaft (71) and impeller
(21) and to replace the wear rings (23) or soft
packed seal sleeves (B26 & B27), it is
necessary to remove the rotating assembly
from the bottom half casing.
Preparation for Removal of the Rotating Assembly
Disconnect the motor coupling.
For pumps fitted with mechanical seals, refer
to the seal manufacturer’s instructions and
lock the seal before removing the retaining
screws (52A) and sliding the seals back from
the face of the insert (A/B53).
Provide a suitable lifting strap and support the
weight of the rotating assembly thus: