APV W+ Series, Manual, Page: 28 / 78

Checking wearing
parts
18
9.
Clean the stator and rotor ring chambers, if necessary with air or
water.
9a.
In the case of water-flushed/aseptic shaft seals, the back plate
must be removed to dismantle the back shaft seal. The back seal
stator ring (pos 16) is mounted in the holding ring (pos 20) and
the rotor ring (pos 15) is mounted on the shaft (pos 6). These are
removed in the same way as the front seal components.
10.
Check O-rings (pos 12,13) for signs of stiffness, lack of elasticity,
brittleness and/or perishing. Replace worn or defective parts.
11.
Check the stator ring (pos 11) and rotor ring (pos 10) for signs of
wear too. The wearing surfaces must be completely free of
scratches/cracks. If not, the rotor ring and stator ring must both
be replaced.
11a.
In the case of water-flushed shaft seals, check the back seal
rings (pos 15,16) for wear too, and replace if necessary.
12.
Fit new O-rings on the stator ring and rotor ring.
NB!
Remember to moisten these with water.
13.
Fit the rotor ring(pos 10) on the impeller without using tools.
NB!
The "notch" in the rotor ring must be fixed so that it fits the
carrier pin (pos 8) in the impeller.
13a.
Where there are water-flushed/aseptic seals, you should also fit a
rotor ring (pos 15) (with O-ring pos 18) on the shaft - again
without using tools.
14.
Fit the stator ring (pos 11) on the back plate without using tools.
NB!
The "notches" in the stator ring must be fixed so that they fit
the carrier in the back plate. Check that the stator ring is posi-
tioned so that it slides back and forward easily in the back plate.
14a.
Where there are water-flushed/aseptic seals, remove the "Drain
pipe" (pos 19) from the stator rings for both the front and back
seal before fitting them in the seal cover (pos 20) and back
plate (pos 7) respectively.
15.
After fitting, clean the wearing surfaces.
15a.
For liquid-flushed/aseptic seals, install the rear flange (Pos. 7).
16.
Fit the impeller (pos 4). Remember to use the proper tension:
M10: 45 Nm
(33 lbf ft)
M14: 70 Nm (52 lbf ft)
M20: 200 Nm (148 lbf ft)
17.
Press the pump body (pos 1) in over the O-ring (pos 3) and
fasten with the clamp ring (pos 2).
Fitting
Positioning the water supply
connections
5 Maintenance