MULTISTAGE PUMP UNIT Russian patent published in 2010 - IPC F04C2/344 F04C11/00 

FIELD: engines and pumps.

SUBSTANCE: proposed device is intended for pumping over of gases, liquids and multi-phase mixes. Device comprises at least two pump stages fitted successively on common shaft. Every said stage represents vane-type positive-displacement pump and comprises rotor 8 arranged inside housing 6 with its inner surface formed by two pairs of symmetric different-radius circular arcs and sections of smooth transition from larger diametre circular arcs to smaller diametre circular arcs. Said rotor is limited by side covers on its faces. Lateral inlet cover has at least two main inlet openings 15 and at least two additional inlet openings 16, while at least two main outlet openings 17 and at least additional outlet openings 18 are made in opposite cover. Flat sectors of inlet cover are turned relative to flat sectors of outlet cover through slant angle. Covers are secured on housing 6 with said flat sectors arranged opposite aforesaid smooth transition sections of rotor inner surface. Stator 7, rotor 8, vanes 10 and side covers are made from hard alloys.

EFFECT: multistage design allows increasing operating pressure multiply with number of vanes by reducing load on every stage.

4 dwg