HALE AP, Technical Manual

Page: 65 / 177

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Table 23. Impeller And Clearance Ring Diameters And Clearance Values
Booster
Pump
Model
Maximum
Clearance Ring
Inner Diameter
in (mm)
Minimum
Impeller Hub
Outer Diameter
in (mm)
Maximum
Acceptable
Radial Clearance
in (mm)
AP 4.777
(121.336)
4.760
(120.904)
0.006 — 0.0085
(0.153 — 0.216)
CBP 3.6326
(92.268)
3.620
(91.948)
0.0045 — 0.0065
(0.114 — 0.165)
MBP 5.638
(143.205)
5.620
(142.748)
0.0075 — 0.01
(0.1905 — 0.254)
RSD
(750-1250 gpm)
6.022
(152.959)
5.987
(152.070)
0.0075 — 0.01
(0.1905 — 0.254)
RSD
(1500 gpm)
6.492
(164.897)
6.419
(163.043)
0.0075 — 0.01
(0.1905 — 0.254)
Often, replacement of the clearance rings will reduce the bypass and restore the pump to near
original performance. A complete restoration requires that the impeller also be replaced. Inspect
the front and back of both clearance ring IDs in several places for signs of wear. Measure the
diameter of each ring in several places. Using a caliper as shown on Figure 14, measure the ID of
each clearance ring and the OD of the impeller.
Figure 15. Measuring For Worn Clearance Rings And Impeller Hubs