MULTISTAGE CENTRIFUGAL DOWNHOLE PUMP STAGE (VERSIONS) Russian patent published in 2011 - IPC F04D13/10 F04D29/62 

FIELD: engines and pumps.

SUBSTANCE: proposed pump stage comprises impeller 1 and guide vane 2. Impeller 1 comprises hub 4, inlet and outlet plates 5 and 6, and vanes 7. Guide vane 2 comprises bush 17, casing 18, inlet and outlet plates 20 and vanes 21. Antifriction bushes 3 are arranged between impeller contact surfaces and on guide vanes, Impeller and guide vane are prefabricated structures. Plates 5, 6, 20 and impeller and guide vane vanes 7, 21 are made from metal sheets and welded together. Hub 4 and impeller flow part, as well as bush 17, guide vane flow section and casing 18 are split elements. Impeller flow section is jointed with hub 4 while and guide vane flow section is jointed with bush 17 and casing 18 by means of latches made up of tabs 8, 22 on outlet plate 6, inlet and outlet plates 20, and by means of stops 15, 25, 28 on hub 4, bush 17 and casing 18. Said joints are locked by flexible rings 26, 29. Outlet plate 6 comprises ledges 9. Deflecting ring 30 is arranged on casing 18.

EFFECT: improved hydraulic characteristics of pump stage, longer life and better reparability.

22 cl, 6 dwg