KSB WKT - Dismantling the Pump Body; Dismantling of Pumps Installed Very Deep Down; Examination of Individual Components; Shafts

WKT
18
7.4.2.3 Dismantling the pump body
After a prolonged period of operation, it
may happen that individual rotor
components (impeller and distance bushes) are difficult to
pull off the shaft, in such cases, do not use force or
hammer blows. First try using a suitable rust solvent or a
puller device. If these measures do not lead to the
desired result, the components concerned can be
warmed up slightly and then pulled off or forced off. The
shaft should remain as cold as possible during the
warming up process. If rotor components are dismantled
by warming up, the shaft should subsequently be
checked for radial run out.
1. Unscrew studs and nuts (902.1 and 920.5) between
distributor casing (10-1) and column pipe main, force
off pump body together with column pipe, and
dismantle distributor casing. Carefully underpin the
drive shaft (213).
2. Dismantle the column pipe.
3. Unscrew the intermediate shaft coupling or
disassemble the muff coupling and remove drive shaft
(213).
4. Unscrew nuts (920.1) of tie rods (905) at suction end,
remove them and pull out the tie rods.
5. Force off suction casing (106).
6. Undo nut (920.2) and remove it together with the lock
washer (931.1).
7. Pull suction impeller (231) off pump shaft (211), and
remove key.
Underpin the stage casing.
8. Force off and remove stage casing (108) including first
stage diffuser (171.1) and suction side bearing. Do not
damage the sealing faces.
9. Pull the stage sleeve (521.1) from the shaft and
remove the split ring (501.2).
10. Pull the impeller (230) off the pump shaft (211) and
remove key. Support the stage casing.
11. Press off and remove the stage casing (108) and
diffuser (171.2).
12. Press the stage sleeve (521) from the shaft.
13. Dismantle all the remaining stages in the same way
as described in points 10 to 12 above.
In the case of multistage pumps, mark the impellers
and stage casings in their correct sequence, to
facilitate reassembly.
14. Pull discharge casing (107) off the shaft and store the
shaft with due care.
7.4.2.4 Dismantling of pumps installed very deep
down
1. Carry out preparations as described in section 7.4.1.
2. Dismantle thrust bearing as described in section
7.4.2.1
3. Dismantle shaft seal as described in section 7.4.2.2.
4. Pull the pumping set far enough out of the barrel by
means of the distributor casing (10-1) to enable a pipe
clip to be attached some 50 cm beneath the next
column pipe joint.
Firmly fasten the pipe clip and lower the pumping set
again until the pipe clip rests on top of the barrel.
Unscrew the pipe joint connecting the lengths of
column pipe main, and lift the distributor casing and
the upper length of column pipe main (711.1) over the
drive shaft. Unscrew the intermediate shaft coupling or
disassemble the muff coupling and remove drive shaft
(213). Force off the complete intermediate shaft
bearing and pull it off over the shaft.
Examine the bearing and shaft for signs of galling
(seizure). If necessary, raise the pumping set by a
further length of column pipe main, again fit a pipe clip
and lower the pumping set until the pipe clip rests on
the barrel. Then dismantle the length of column pipe
main and the bearing. Lift the pump body out of the
barrel, then set it down and underpin it in the
horizontal position for dismantling.
5. Dismantle the pump body in accordance with section
7.4.2.3, points 4 to 14.
7.4.3 Examination of individual components
7.4.3.1 Shafts (211, 212, 213)
Inspect the bearing sleeves (529) on the shafts for signs
of galling (seizure). Slight traces of damage can be
removed by grinding within the permissible clearance
limits. If the touching up works should result in the
permissible clearances being exceeded, then new
bearing sleeves (529) must be placed on.
Carry out an out-of-round check on a lathe between dead
centres. The max. permissible shaft whip must not
exceed 0,03 mm.
Make sure the shaft is accurately
centered on the lathe, as otherwise the
readings will be erroneous.
If certain rotor components are replaced by new ones, or
have been touched up, or if a new shaft has been fitted,
the pump rotor must be balanced dynamically, preferably
at the max, operating speed of the pump, but at least at
1000 1/min. The max. permissible residual eccentricity is
5 microns.
7.4.3.2 Bearing arrangement
Antifriction bearings (320)
Even if they only exhibit slight discoloration marks or
specks of rust, or signs of damage to the running
surfaces, the bearings must be replaced by new ones.
Caution
Caution