MULTI-STAGE SUBMERSIBLE PUMP Russian patent published in 1999 - IPC

FIELD: pumping-out formation fluid. SUBSTANCE: pump has many stages connected in succession. Each stage is provided with impeller including drive and driven disks with blades arranged between them and guide apparatus with vanes. Mounted over periphery of driven disk of impeller on its lateral surface are three-sided cells open on outer side of disks; surface of inner wall of guide apparatus has lateral circular passage. Distance between surface of lateral circular passage on guide apparatus of one stage and upper edge of cells on impeller of other stage is at least 0.3 of depth of cells and length of cells in radial direction is no more than 0.3 of radius of driven disk. EFFECT: increased pressure head at low output; enhanced stability of working characteristics in case of gas bubbles in fluid being handled. 3 cl, 1 dwg