STAGE OF MULTI-STAGE CENTRIFUGAL PUMP Russian patent published in 2011 - IPC F04D13/10 F04D29/41 

FIELD: engines and pumps.

SUBSTANCE: stage of multi-stage centrifugal pump consists of impeller 1 and pump diffuser with collar-axle bearing. Impeller 1 has drive and driven discs 3, 4 with blades 5 located between them forming flowing cavities. Impeller 1 is installed with the possibility of free movement along pump shaft within collar-axle bearings of mated diffusers. In coupling place of at least one blade 5 of impeller 1 with drive and driven discs 3, 4 there is at least one through-hole 9 forming a channel isolated from flowing cavities. The channel goes through blade 5 and both discs 3, 4. The channel connects both areas adjacent to discs 3, 4 outer surfaces.

EFFECT: increase of pump efficiency and stage-head within delivery range by means of provision impeller lower position in delivery range.

3 cl, 2 dwg