Modular compact pump

Abstract

The present invention relates to a modularized pump. The pump has end lids 12, 13 with an inlet and an outlet for pumped fluid, and at least two pump modules 7 sandwiched between the end lids 12,13. Each pump module includes a casing 1 with an enclosed volume 20 and at least two pump stages 6. At least one coolant inlet 10 and outlet and a separate power connection 16 for connection to a VSD is included in each module. Each pump stage 6 includes an impeller 5 with a rotor 4, a stator 2 surrounding the rotor 4, provided to drive the rotor and a can 3 between the impeller 5 and the stator 2.

1 . A modularized pump comprising an inlet side end lid with a process fluid inlet and an outlet side end lid with a process fluid outlet and at least two pump modules sandwiched between the inlet side end lid and the outlet side end lid, each pump module including a casing, an enclosed volume inside said casing, at least one pump stage, at least one coolant inlet, at least one coolant outlet and a separate power connection for connection to a VSD; and
 wherein each pump stage includes an impeller with a rotor, a stator surrounding the rotor, and a can between the impeller and the stator.   
     
     
         2 . The modularized pump of  claim 1 , wherein each module includes a pressure compensator limiting a pressure difference over the can between a pumped media in an impeller side of the modularized pump and a dielectric fluid inside the casing. 
     
     
         3 . The modularized pump of  claim 1 , wherein the at least one coolant inlet, and the at least one coolant outlet are in fluid communication with spiral shaped coolant channels surrounding each stator. 
     
     
         4 . The modularized pump of  claim 1 , further including a metal to metal face seal between the at least two modules. 
     
     
         5 . The modularized pump of  claim 1 , further including a polymeric face seal between the at least two modules. 
     
     
         6 . The modularized pump of  claim 1 , wherein each module includes two stages.