7.5.6.2
Fitting the bellmouth for pressure class B
On impellers of pressure class B, the outer contour of the vanes and the inner
contour of the casing wear ring are spherical.
For this pressure class the clearance is axially adjusted with the impeller nut.
502
112
138
901.01
922
903.06
914.07
230
902.01
920.01
550.01
Fig. 26: Impeller of pressure class B
✓
Bellmouth 138 has been positioned on wooden supports on a level and solid
surface.
✓
Suitable hoisting tackle is provided.
✓
The pump set has been completely pre-assembled.
✓
A new casing wear ring 502 has been fitted in bellmouth 138.
1.
Attach a lifting accessory to eyebolts 900.
2.
Carefully pull the pump set upright by means of the lifting accessory and
hoisting tackle.
3.
Center the pump set above bellmouth 138.
4.
Slowly lower the pump set. While lowering the pump set, make sure that studs
920.01 are aligned with the drilled holes.
5.
Lower the pump set until it sits on bellmouth 138.
6.
Fasten all studs 902.01 with corresponding nuts 920.01 and discs 550.01.
Observe the tightening torque!
7.
Close the threaded holes with screw plugs 903.05.
8.
Loosen the impeller nut to adjust clearance "A" between impeller 230 and
casing wear ring 502.
9.
Use a sensor to check that the required clearance "A" is met, see the following
table.
10. Align the holes of impeller 230 and impeller nut 922 and fasten them with
hexagon socket head cap screws 914.07.
Table 16: Clearance "A"
Type series
Standard
A [mm] / [inch]
Large clearance
4)
A [mm] / [inch]
700 - 470
0.4 / 0.0157
1.2 / 0.0472
800 - 540
0.5 / 0.0197
1.3 / 0.0512
900 - 540
0.5 / 0.0197
1.5 / 0.0591
1000 - 700
0.7 / 0.0276
1.7 / 0.0669
1200 - 870
0.9 / 0.0354
2.0 / 0.0787
1500 - 1060
1.1 / 0.0433
2.0 / 0.0787
4)
For activated sludge or fluids containing long fibers
7 Servicing/Maintenance
50 of 68
Amacan P
