WACKER Group 0007659, Repair Manual

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PG Pumps Maintenance
wc_tx000607gb.fm
23
4.3 Adjusting Impeller Clearance
See Graphic: wc_gr000838
If it is necessary to replace impeller or volute, be sure clearance
between impeller and volute is adjusted correctly. The impeller
(a)
should be as close to the volute (b) as possible without rubbing against
it. Clearance is adjusted by adding or removing shims (c) from behind
impeller. To adjust the clearance do the following:
4.3.1 Remove pump housing but do not remove impeller.
4.3.2 Measure the distance (d) of volute.
4.3.3 Measure the distance (e) of impeller.
4.3.4 Subtract the distance (e) from (d) .
(d) - (e) = (f) clearance.
4.3.5 The clearance between the volute and the impeller should be 0.3 mm
(0.012 in.) to 0.7 mm (0.028 in.). Adjust the distance by removing the
impeller and adding shims as needed.
Each shim measures 0.3 mm (0.012 in.).
As the impeller wears down, additional shims may be required to
maintain the clearance between the impeller and the volute. Check the
clearance whenever the mechanical seal
(g) , impeller, volute, or rear
flange plate are replaced.
w c _ g r 0 0 0 8 3 8
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A
C
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B
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