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

FIELD: oil engineering; multi-stage oil well pumps for pumping out formation fluid. SUBSTANCE: stage of submersible multi-stage pump includes impeller with drive and driven disks and blades between them and guide apparatus with profiled blades whose leading edges extend beyond external diameter of outer cover of apparatus. Three sided cells open on external side of disk are mounted on lateral surface of impeller drive disk over its periphery. Lateral circular passage is provided on surface of outer cover of guide apparatus which is engageable with impeller. Distance between surface of lateral circular passage on guide apparatus and upper edge of cells on impeller is no less than 0.3 of their depth; length of cells in radial direction is no more than 0.3 of radius of drive disk. EFFECT: increased head at low delivery and enhanced stability of working characteristics in case of presence of gas bubbles in medium being handled. 3 cl, 1 dwg