Variable Pump

Abstract

The present invention relates to a centrifugal pump and a method of varying the properties of a centrifugal pump. The centrifugal pump has a pump housing, which in the preferred form comprises a front casing 22 and a back casing 24 . The pump also includes an impeller 26 . The present invention provides the centrifugal pump with one or more grooves 29 in the housing adjacent the impeller 26 . The one or more grooves are adapted to removably receive a cutwater 28.

1 - 23 . (canceled) 
   
   
       24 . A centrifugal pump having a pump housing and an impeller, the centrifugal pump comprising one or more grooves provided in the housing adjacent the impeller to removably receive a cutwater, wherein the one or more grooves are adapted to interchangeably receive different-sized cutwaters. 
   
   
       25 . The centrifugal pump as claimed in  claim 24  wherein the pump housing comprises two housing halves that are attached together, with grooves provided in each housing half. 
   
   
       26 . The centrifugal pump as claimed in  claim 24  wherein two or more discrete grooves are provided in the pump housing. 
   
   
       27 . The centrifugal pump as claimed in  claim 24  wherein a single continuous groove is provided in the pump housing. 
   
   
       28 . The centrifugal pump as claimed in  claim 27  wherein ridge-like formations are provided in the continuous groove. 
   
   
       29 . The centrifugal pump as claimed in  claim 24  wherein the cutwater comprises a strip of plastic or metal. 
   
   
       30 . The centrifugal pump as claimed in  claim 29  wherein the cutwater is provided in a single size from which smaller sizes may be made by machining the cutwater. 
   
   
       31 . The centrifugal pump as claimed in  claim 29  wherein the cutwater is provided in various discrete sizes. 
   
   
       32 . The centrifugal pump as claimed in  claim 31  wherein the various sizes may be machined to a specific size. 
   
   
       33 . The centrifugal pump as claimed in  claim 24  wherein the cutwater comprises a pre-curved strip of material. 
   
   
       34 . The centrifugal pump as claimed in  claim 24  wherein the cutwater comprises a flexible strip of material that can be curved for insertion into the one or more grooves. 
   
   
       35 . A centrifugal pump housing to receive an impeller, the pump housing including one or more grooves to removably receive a cutwater, wherein the one or more grooves are adapted to interchangeably receive different-sized cutwaters. 
   
   
       36 . A centrifugal pump adapted to receive different-sized impellers, the centrifugal pump comprising a housing having one or more grooves to receive a cutwater, wherein the one or more grooves are positioned such that different-sized cutwaters may be interchangeably placed adjacent the periphery of different-sized impellers. 
   
   
       37 . A method for varying the operating characteristics of a centrifugal pump, the pump having an interchangeable impeller and one or more grooves to interchangeably receive different-sized cutwaters, the method comprising:
 selecting an impeller having one or more desired characteristics,   selecting a cutwater for use with the selected impeller, and   installing the selected impeller and cutwater into the centrifugal pump.   
   
   
       38 . The method as claimed in  claim 37  wherein selecting an impeller comprises selecting an impeller with a desired diameter. 
   
   
       39 . The method as claimed in  claim 37  wherein selecting an impeller comprises selecting an impeller with a desired contour. 
   
   
       40 . The method as claimed in  claim 37  further comprising machining the selected cutwater to better suit the selected impeller before the step of installing the cutwater into the centrifugal pump. 
   
   
       41 . The method as claimed in  claim 37  further comprising:
 removing the selected cutwater from the pump,   machining the selected cutwater to better suit the selected impeller, and   installing the machined cutwater into the centrifugal pump.   
   
   
       42 . The method as claimed in  claim 37  further comprising:
 removing the selected cutwater from the pump,   selecting a replacement cutwater, and   installing the replacement cutwater into the centrifugal pump.   
   
   
       43 . A method for varying the operating characteristics of a centrifugal pump, the pump having an interchangeable impeller and a housing provided with one or more grooves to interchangeably receive different-sized cutwaters, the method comprising:
 disassembling the pump so as to gain access to the impeller and cutwater,   removing the cutwater from the one or more grooves,   machining or replacing the cutwater,   inserting the machined or replacement cutwater into the one or more grooves, and   reassembling the pump.   
   
   
       44 . The method as claimed in  claim 43  further comprising:
 removing the impeller,   machining or replacing the impeller, and   inserting the machined or replacement impeller into the pump.