WACKER Group 0007659, Руководство по ремонту

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Disassembly/Assembly Procedures PG Repair
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5.4 Description and Operation
See Graphic: wc_gr003495
PG Series Pumps use an impeller (1) and volute (2) to create the
suction and discharge pressures required for pump operation.
The impeller is threaded directly to the engine drive shaft (3) and
rotates inside the volute casing. Water is drawn into the pump inlet (4)
by the low pressure area created at the eye of the impeller. Vanes on
the impeller move the liquid into the volute where it is gathered and
directed to the discharge port (5).
Clearance between the impeller and the volute is maintained by the
addition of shim washers (6) behind the impeller.
A mechanical seal (8), mounted behind the impeller, prevents water
from running along the engine drive shaft and seals the rear of the
pump housing to prevent leakage.
The flapper valve (9) at the pump inlet closes when the pump stops.
This valve seals the inlet port and prevents the prime water in the
suction hose from being lost.
The pump case is easily filled with water by removing the priming plug
(10).