SPP Pumps Unistream - Manual (Page 12)

Manual No/Rev
W21-002E / 10
Operators Instructions for
Unistream Centrifugal Pumps
Our policy is one of continuous improvement and we reserve the right to alter specifications at any time
Page 12 of 24
Undo the impeller nut (92.2) in a counter
clockwise direction and withdraw the impeller
(23.0) from the shaft (21.1).
For pumps fitted with a soft packed stuffing
box:
Removal of the packed stuffing box depends
on the pump construction:
a)
For pumps with shaft sizes 25, 35 and 45
with a bolted casing cover construction only,
remove stud nuts (92.02) from the bearing
housing
first, before proceeding with
instruction b).
For pumps with shaft size 25 or 35 and with
clamped
casing cover construction,
commence disassembly with instruction b).
b)
Using screwdrivers or similar tools as levers
in the recesses provided, carefully prise
apart and remove the casing cover (16.1)
complete with stuffing box packing (46.1),
lantern ring (45.8) and gland (45.2), from the
bearing housing (33.0).
c)
Dismantle the shaft sleeve (52.4), gland
(45.2), stuffing box packing (46.1) and
lantern ring (45.8).
For pumps fitted with a mechanical seal:
Remove the impeller key (94.01) and
carefully withdraw the shaft sleeve (52.3)
complete with the rotating element of the
mechanical seal (43.3).
Note: If after examination of the rotating
element, it is found necessary to remove the
rubber bellows from the shaft sleeve, the
complete mechanical seal assembly will
have to be replaced.
Removal of the mechanical seal depends on
the pump construction:
For pumps with shaft sizes 25, 35 and 45
with a bolted casing cover construction only.
a) Remove stud nuts (92.02) from the bearing
housing
first, before proceeding with
instruction b).
For pumps with shaft size 25 or 35 and with
clamped
casing cover construction,
commence with instruction b).
b)
Using screwdrivers or similar tools as levers
in the recesses provided, carefully prise
apart and remove the casing cover (16.1)
complete with the stationery element of the
mechanical seal (43.3), from the bearing
housing (33.0). Care must be taken to
ensure that the stationery element of the
seal and the shaft are not damaged when
extracting the shaft.
c)
The stationery element of the seal may be
removed from the casing cover by pressing
out by hand from the drive end. If the
stationery element is damaged or shows
signs of wear, it must be replaced.
Pull off thrower (50.7) from shaft (21.1).
Unscrew the hexagon screws (90.1) and
remove both bearing covers (36.0) from the
bearing housing (33.0).
Using a soft faced hammer or suitable drift,
carefully drive the pump shaft (21.1) out with
its bearings in the direction of the drive end,
i.e. away from the pump end, ensuring that
the impeller nut thread is not damaged.
Care must be taken to ensure that the pump
end bearing passes centrally through the
bore of the drive end bearing housing.
The bearings (32.1) may be cleaned and
checked without removing them from the
shaft. If they need to be replaced, remove
them by use of a suitable puller or by
applying force to the inner ring using a drift
or punch, taking care to turn the shaft such
that the inner ring is kept square to the shaft
until the bearing is free.
Pump & Drive End Bearing Specifications
Shaft Unit 25 35 45
Bearing
Specification
DIN 625 6305
C3 6307
C3 6309
C3
If the bearings (32.1) are to be re-used,
ensure they are thoroughly flushed with
white spirit or similar cleaning fluid, dried and
protected to prevent any abrasive media
from coming into contact with the races balls
and rollers. Bearings should be lightly oiled
and wrapped for storage.
Check the shaft (21.1) for straightness by
mounting between centres and measuring
the runout with a dial gauge at the coupling,
bearing, sleeve and impeller positions. Fit
the stuffing box sleeve and check again on
this diameter. The run-out should not exceed
0.08 mm in any of the positions measured.
Wear rings may be measured and compared
with the dimensions shown in the table
below. If pump efficiency has reduced the
wear rings may be replaced, contact the
SPP Pumps Ltd. Spares and Service
Departments for fitting new wear rings.