Centrifugal electric pump

Abstract

A centrifugal electric pump, of the type comprising a shell for the containment of a set of impellers, interleaved with fixed diffusers and of a motor that drives the impellers to rotate, since they are keyed on a same shaft as the motor, a sealing chamber is provided between the impellers and the motor and is extended around the shaft to collect condensation water and water seepage originating from the set of impellers, the sealing chamber is connected to the outside of the pump by means of at least one water discharge duct.

What is claimed is: 
     
         1 . A centrifugal electric pump, of the type comprising a shell for the containment of a set of impellers interleaved with fixed diffusers, and of a motor that drives said impellers to rotate, since they are keyed on a same shaft as said motor, said pump being wherein a sealing chamber is provided between said impellers and said motor and is extended around said shaft to collect condensation water and water seepage originating from the set of said impellers, said sealing chamber being connected to the outside of said pump by means of at least one water discharge duct. 
     
     
         2 . The pump according to  claim 1 , wherein said shell has at least one discharge hole at said at least one discharge duct. 
     
     
         3 . The pump according to  claim 2 , wherein said shell comprises a substantially cylindrical portion, which surrounds said impellers, said sealing chamber and said motor, and is constituted by two jackets which are mated on the transverse plane at said discharge hole and two opposite heads for closing the end faces of said cylindrical portion, respectively a first head at the intake and a second head at the delivery of the pump. 
     
     
         4 . The pump according to  claim 3 , wherein said two jackets are substantially two cylindrical bodies which are hollow and open at their end faces, have the same shape and dimensions and are coupled symmetrically on the transverse plane so as to constitute the substantially cylindrical portion of said shell. 
     
     
         5 . The pump according to  claim 4 , wherein each one of said jackets has, at its two opposite end faces, respectively a first flange and a second flange, the latter for mating with the other one of said jackets. 
     
     
         6 . The pump according to  claim 5 , wherein said second flange is provided laterally with one half of said discharge hole, said jackets, by mating symmetrically, providing said discharge hole. 
     
     
         7 . The pump according to  claim 5 , wherein said two jackets and said first and second heads that compose said shell are joined by means of threaded tension members that pass in succession through:
 a first annular element of said first head and said first flange of the jacket that surrounds said impellers, with which said first head and said jacket are associated,   said two second flanges of said two jackets, at right angles to the transverse plane on which they mate,   said first flange of the jacket that surrounds said motor, and a second annular element of said second head, with which said jacket and said second head are associated.   
     
     
         8 . The pump according to  claim 3 , wherein said first head has at least one duct for aspirating the flow that enters said impellers and said second head has at least one duct for delivery of the flow. 
     
     
         9 . The pump according to  claim 3 , wherein each one of said two jackets has stiffening ribs.