HORIZONTAL PUMP UNIT WITH UNIT OF PRIMARY STAGE AND SEPARATE UNIT OF STAGE WITH HEAD ON SUCTION SIDE OF PUMP (NPSH) (VERSIONS) Russian patent published in 2020 - IPC F04D9/04 F04D1/06 F04D13/06 

FIELD: engines and pumps.

SUBSTANCE: invention relates to the field of pumping units characterized by low effective pressure on the suction side of the pump. Horizontal pump unit comprises motor, suction chamber and pump driven by motor. Pump comprises a primary stage assembly comprising a pump housing and a step assembly with a low head on the pump suction side (NPSH), connected between unit of primary stage and suction chamber and containing diffuser connected between pump housing and suction chamber, impeller located inside diffuser, and intermediate shaft. Unit of stage with low NPSH is located outside relative to unit of primary stage. Unit of stage with low NPSH comprises diffuser connected to pump housing and impeller with low NPSH located inside diffuser. Diameter of stage assembly with low NPSH, as an option, exceeds diameter of primary stage assembly.

EFFECT: low input flow coefficient.

18 cl, 10 dwg