●　增强型反向环流型（HR）

●　Reverse Circulation with adapter(HR Type)

结构上由于电机腔体内的压力接近泵的出口压力，适用于介质的饱和蒸汽压较高的液体如液化气，氯乙烯等。

Pressure in rotor chamber is the same as discharge pressure, Avoiding evaporation in rotor chamber,Self venting at start-up,Liquids with rapidly increasing,vapour pressure,i.e liquefied gases,VCM,hydrocarbons,chlorine.