MULTI-STAGE CENTRIFUGAL PUMP Russian patent published in 1998 - IPC

FIELD: handling various fluids; production of oil. SUBSTANCE: pump has shaft on which impellers are fitted. Impeller of each stage is located between two adjacent guide vanes at radial and axial clearances. Impeller is made in form of hub on which open blades are mounted at acute angle of inclination at outlet relative to plane perpendicular to axis of rotation. Lower end of hub is mounted on inner ring of previous guide vane. Outer radius of cover disk and plate separating two adjacent passages of guide vane is reducing from the beginning of concave wall of passage to minimum distance between concave and convex walls of next passage. Circular chamber is formed between passages of guide vanes and its inner ring. Outlet angle is lesser than 90 deg. EFFECT: enhanced operational reliability; increased pressure head and enhanced efficiency. 2 dwg