Centrifugal pump intake pipe with a helical flow path

Abstract

An intake pipe for directing a slurry towards an impeller of a centrifugal pump defines a helical flow path oriented to swirl the slurry in a rotational direction of the impeller.

We claim: 
     
         1 . An intake pipe for directing a slurry towards an impeller of a centrifugal pump, wherein the intake pipe defines a helical flow path oriented to swirl the slurry in a rotational direction of the impeller. 
     
     
         2 . The intake pipe as claimed in  claim 1 , wherein the intake pipe comprises a helical portion having a diameter and a length, a pitch over diameter of about 2, and an eccentricity radius over diameter of about 0.2. 
     
     
         3 . The intake pipe as claimed in  claim 1 , wherein the intake pipe comprises a helical portion having a length of about 15,000 mm, a pitch of about 1,500 mm, and an eccentricity radius of about 150 mm. 
     
     
         4 . The intake pipe as claimed in  claim 1 , wherein the intake pipe comprises a helical portion having a length of 15,000 mm, a pitch of 1,500 mm, and an eccentricity radius of 150 mm. 
     
     
         5 . A pump assembly for a slurry, the assembly comprising:
 (a) a volute defining an axial pump inlet, a radial pump outlet, and a pump chamber for an impeller rotatable about an axial impeller axis; and   (b) an intake pipe in fluid communication with the pump inlet and defining a helical flow path oriented to swirl the slurry in a rotational direction of the impeller.   
     
     
         6 . The pump assembly as claimed in  claim 5 , wherein the intake pipe comprises a helical portion having a diameter and a length, a pitch over diameter of about 2, and an eccentricity radius over diameter of about 0.2. 
     
     
         7 . The pump assembly as claimed in  claim 5 , wherein the intake pipe comprises a helical portion having a length of 15,000 mm, a pitch of 1,500 mm, and an eccentricity radius of 150 mm. 
     
     
         8 . A pump system comprising:
 (a) a first pump;   (b) a second pump, wherein the second pump is a centrifugal pump comprising an impeller; and   (c) an intake pipe for directing a slurry from the first pump to the impeller of the second pump, wherein the intake pipe defines a helical flow path oriented to swirl the slurry in a rotational direction of the impeller.   
     
     
         9 . The pump assembly as claimed in  claim 8 , wherein the intake pipe comprises a helical portion having a diameter and a length, a pitch over diameter of about 2, and an eccentricity radius over diameter of about 0.2. 
     
     
         10 . The pump system as claimed in  claim 8 , wherein the intake pipe comprises a helical portion having a length of 15,000 mm, a pitch of 1,500 mm, and an eccentricity radius of 150 mm.