摘要：Both twin--screw and helico-axial pumps were operated successfully and consideredavailable for onshore and offshoye development. The multiphase pump can reach to itshighest efficiency only at the design point, which is far lower than ordinary pump. So howto design the multiphase pump and how to increase the efficiency of the pump are the focusof researchers’ attention. This paper presents some discussions on the multiphase pump andefficiency of pump, on the basic of this, a conceptual design method--named as segmentalincompressible method and variable compression efficiency are given.