SPP Pumps Thrustream - Manual (Page 11)

Operators Instructions for Horizontal
Standard Thrustream Centrifugal Pumps
Manual No/Rev
W12-003E / 6
Our policy is one of continuous improvement and we reserve the right to alter specifications at any time
Page 11 of 28
6.2 Preparation for Maintenance
Electric Shock & Accidental Starting
Hazard
ISOLATE the equipment before any
maintenance work is done. Switch off the
mains supply, remove fuses, apply lock-outs
where applicable and affix suitable isolation
warning signs to prevent inadvertent re-
connection.
During maintenance personnel should be
aware of the risks of inhaling dangerous
fumes or vapours.
No special tools are required for pump
dismantling and re-assembly. However, it is
important to ensure the suitable lifting
equipment is available and that the work is
carried out in a clean area.
6.3 Repacking the Stuffing Box
Where a soft packed gland seal is fitted it will
be necessary to replace the packing rings
periodically when the gland can no longer be
tightened to reduce leakage to the normal
level, or if the gland is overheating.
Packing Removal Procedure
1 Close the suction & discharge valves and
release pressure from the casing, remove the
gland retaining nuts (41C) and pull the gland
(50) clear of the stuffing box.
47
47R 51 71
41C
41G
50
2
Carefully withdraw the old packing and lantern
ring (46), using a pair of extractor tools of the
correct size placed on opposite sides of the
pump shaft (71).
3 Clean the sleeve, the bore of stuffing box, the
lantern ring and the split gland with a clean oily
cloth.
50 51
4
Check the sleeve for concentricity with the
stuffing box bore and that that the surface
under the packing rings is free from scores,
pitting or grooves.
5
Examine the gland for general condition and
replace if damaged.
Packing Preparation
6 If the packing is to be cut from a coil or long
length the size, number of rings and length is
thus:
Stuffing Box Data
PUMP
SHAFT
MODULE
SLEEVE
DIA.
mm
PACKING SIZE
SIZE of
RING
ID x OD
mm x mm
NO. OF
RINGS
PER
BOX
SQUARE
SECTION
mm
LENGTH
of ONE
RING
mm
1 45 10 173 45 x 65 4
2 61 12 230 61 x 85 4
3 76 15 283 75 x 100 4
7 Wrap the packing around a dummy shaft, of
the same diameter as the sleeve.
8 To assist in cutting rings, two guide lines
parallel to the shaft axis and separated by a
distance equal to the packing section may be
drawn on the spiral.
9
Cut each ring from the spiral at an angle of 45°
diagonally across the guidelines.