SPP Pumps Unistream - Manual (Page 11)

Operators Instructions for
Unistream Centrifugal Pumps
Manual No/Rev
W21-002E / 10
Our policy is one of continuous improvement and we reserve the right to alter specifications at any time
Page 11 of 24
and without Lantern Ring 6 6 6
If the packing rings are to be cut from a coil,
or length of packing, the size, number of
rings and length are shown in the tables.
Wrap the packing strip around a dummy
shaft of the required diameter, overlapping
the coils as shown. Cut diagonally at 45° to
produce rings with an overlapped split joint.
Note that if packing is cut from flat material
or with square joint lines, a good seal will not
be achieved.
6.3.3 Re-packing
Insert the first ring and gently push it to the
bottom of the stuffing box using a suitable
tool taking care not to score the sleeve or
stuffing box bore.
Install the lantern ring checking that its
position coincides with the lubrication
connection.
Insert the second ring as above but with its
joint advanced by 120° from the first ring's
joint position.
Install the required number of further rings to
complete the packing ensuring that the last
ring fitted does not protrude from the stuffing
box bore.
Refit the gland (45.2) and tighten the
retaining nuts finger tight only.
Run the pump for 10 minutes at full pressure
and tighten the retaining nuts by 1/6 of a turn
(one flat). Repeat this at ten-minute intervals
until leakage is reduced to a trickle (30 to
120 drops per minute), this being required to
ensure that the gland packing is lubricated.
6.3 Maintenance of Mechanical Seals
Generally there are is no maintenance
required on mechanical seals, but if it is
required, the manufacturer's information is
given in Appendix l.
6.4 Bearing Lubrication
It is important to maintain the correct level of
oil in the bearing housing. The level must be
maintained at the mark on the sight glass on
the side of the bearing housing.
Avoid over filling with oil that will cause the
bearings to overheat.
If the bearing temperature is always below
50°C, change the oil once per year. If the
pump bearings reach 80°C or if there is a
risk of oil contamination, change the oil every
6 months or after 5000 hours running.
Oil Capacity of Bearing Housings
Shaft Unit 25 35 45
Capacity in Litres 0.2 0.55 0.9
Recommended Lubricants:
International
Standard /
As Supplied
For continuous bearing
temperatures up to 80°C
Speed up to
1500 rpm.
Speed above
1500 rpm.
Standard ISO VG 100 ISO VG 68
TEXACO RANDO
HD 100 RANDO
HD 68
6.5 Disassembly of the Pump
Refer to Section 8 - Pump Cross-Section
Drawings.
The pump is designed to allow removal of
the bearing housing, shaft and impeller
assembly
without disconnecting the
pipework. If the pump is fitted with a spacer
coupling, the motor need not be removed.
Remove coupling and motor if necessary to
allow withdrawal of the pump assembly.
Remove the bolts connecting the bearing
mounting bracket (18.3) to the baseplate.
If fitted, disconnect the seal lubrication
pipe(s) and drain the bearing housing by
removal of the drain plug (90.31).
Unscrew the nuts (92.0) from the volute
casing studs.
Remove the casing cover (16.1) and the
bearing housing (33.0) complete with rotor
using screwdrivers or similar tools as levers
in the gap between the volute casing (10.2)
and the casing cover (16.1).