MULTI-STAGE SUBMERSIBLE PUMP (VERSIONS) Russian patent published in 2014 - IPC F04D13/10 F04D29/62 

FIELD: engines and pumps.

SUBSTANCE: multi-stage submersible pump is described in the application. Impellers are pressed with wavy springs (51) to hold rotary blades (37) of impellers near appropriate guide vanes (21). The full row of impellers is assembled to ensure their adjacency to each other via wavy springs (51) and permanent axial load. Wavy springs (51) also absorb any variations of permissible deviations in the row of impellers for their retention in the correct working position. To retain impellers in their correct positions they also use thrust orifices (61) from hard materials placed between adjacent impellers making it possible to avoid their erosion.

EFFECT: invention is aimed at provision of steps creation with a shorter row of wheels, which makes it possible to produce more steps and higher head in respect to a certain body.

18 cl, 7 dwg