WK
11.5 Inspection of individual Pump Components
1.
Shaft (210)
Check true running (out-of-round) between centres on a
lathe. Max. permissible out-of-round (shaft whip) : 0.03
mm. In principle, a bent shaft should never be straightened
out, either warm or cold, but replaced by a new shaft if
the permissible shaft whip is exceeded.
Caution : Make sure the shaft is accurately centred on
the lathe as otherwise erroneous measurement results
will be obtained.
2.
Stage Casings (108)
Examine al contact faces for flawless condition. The plane
parallelism of the contact faces must be checked at 4
points around the circumference. The deviation should
not exceed 0.05 mm. Touch up any damage contact faces
on a lathe. The surface roughness must not exceed
Ra = 1.6 m.
3.
Bearings (322)
The bearings should be replaced by new ones even if
there are only slight discolorations or rust specks, or signs
of damage on the contact faces tracks and ball or rollers.
The outer race of the cylindrical roller bearing should be
inserted as illustrated in Fig. 76.
Fig. 75 Stacking the stage casings on top of one another
As new clearance
Max. permissible clearance
for material alternative
value for material alternative
Chrome steel
Chrome steel
C.I. Bz
throughout
C.I. Bz
throughout
and bronze
and bronze
mm on dia.
mm on dia.
mm on dia.
mm. on dia.
Casing Wearing ring Impeller neck
0.30
0.40
1.0
1.0
Diffuser -- stage sleeve
0.30
0.35
1.0
1.0
Discharge casing -- spacer sleeves
0.30
0.35
1.0
1.0
Suction head
Shaft -- Suction casing
1.0
1.0
2.0
2.0
operation
Fig. 76 Inserting the outer race of the roller bearing
Observe the greatest cleanliness when mounting the
bearings (322). If the existing bearings are to be used
again, they should be cleaned with petrol gasoline or
benzol. After washing, they should immediately be
sparyed with oil.
4. Impellers (230) spacer sleeve suction/discharge (525),
stage sleeve (521), Casing Wearing Rings (502) and
Diffusers (171).
Inspect the impellers (230) for signs of damage by solids
entrained with the fluid pumped.
The impeller necks -- in the case of material construction
CA6NM (chrome steel construction throughout) these are
provided with impeller wearing rings (503) -- and the
casing wearing rings (502, stage sleeve diffusers in the
Fig. 77 Alternative material construction in chrome steel
throughout (e.g. CA6NM)
540.2
503
171.2
400.2
541
521
106
210
107
412.2
230
108
171.1
502
540.3
525.1
525.2
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