Sealing Rings for Abrasive Slurry Pumps

Abstract

There are a number of applications today where the pumping of abrasive slurries is necessary. The pumping mechanisms, though, can be complex, employing multiple transfer cylinders and movable pipes. These designs have their problems, specifically wear between poorly sealing surfaces. To reduce this problem, seals are provided that have multiple wear surfaces which include harder tiles secured over a softer core to benefit from the relative hardness or flexibility of each of the respective materials.

1 .- 9 . (canceled) 
   
   
       10 . A pipe seal for an abrasive materials pump, comprising:
 a base ring formed of a fracture-tough metal, the base ring having opposing front and rear faces;   an aperture extending through the base ring from the front face to the rear face, the aperture having an inner surface;   at least one inner-surface tile formed of a hard metal and secured to the inner surface of the aperture;   at least one front face tile formed of a hard metal and secured to the front face of the base ring adjacent the aperture; and   at least one second face tile formed of hard metal and secured to the front face of the base ring and spaced-apart from the aperture, the second face tile being harder than the fracture-tough metal, the inner-surface tile being harder than the second face tile, and the face tile being harder than the inner-surface tile.   
   
   
       11 . The pipe seal according to  claim 10 , wherein the fracture-tough metal is steel and the hard metal is tungsten carbide. 
   
   
       12 . The pipe seal according to  claim 10 , wherein the tiles are secured to the base ring by brazing. 
   
   
       13 . The pipe seal according to  claim 10 , wherein the aperture is circular and the inner surface is generally cylindrical. 
   
   
       14 . The pipe seal according to  claim 10 , wherein:
 the at least one inner-surface tile is a plurality of tiles that form a substantially continuous wear surface on the inner surface of the base ring;   the at least one front face tile is a plurality of tiles that forms a substantially continuous wear surface on the front face of the base ring adjacent and surrounding the aperture; and   the at least one second face tile is a plurality of tiles that forms a substantially continuous wear surface on the front face of the base ring surrounding the front face tiles.   
   
   
       15 . A pump assembly for moving abrasive slurries, the pump assembly comprising:
 a pair of slurry conduits, each conduit having a circular opening;   a transfer conduit having a circular opening, the opening of the transfer conduit being movable between the openings of each of the pair of conduits to establish fluid communication between one of the slurry conduits and the transfer conduit; and   a seal ring associated with at least one of the openings in the slurry and transfer conduits, the seal ring including:
 a base ring formed of a fracture-tough metal, the base ring having opposing front and rear faces; 
 an aperture extending through the base ring from the front face to the rear face, the aperture having an inner surface; 
 at least one inner-surface tile formed of a hard metal and secured to the inner surface of the aperture; 
 at least one inner face tile formed of a hard metal and secured to the front face of the base ring adjacent the aperture; and 
 at least one outer face tile formed of hard metal and secured to the front face of the base ring and spaced-apart from the aperture, the outer face tile being harder than the fracture-tough metal, the inner-surface tile being harder than the outer face tile, and the inner face tile being harder than the inner-surface tile. 
   
   
   
       16 . The pump assembly according to  claim 15 , wherein the fracture-tough metal is steel and the hard metal is tungsten carbide. 
   
   
       17 . The pump assembly according to  claim 15 , wherein the tiles are secured to the base ring by brazing. 
   
   
       18 . The pump assembly according to  claim 15 , wherein:
 the at least one inner-surface tile is a plurality of tiles that forms a substantially continuous wear surface on the inner surface of the base ring;   the at least one front face tile is a plurality of tiles that forms a substantially continuous wear surface on the front face of the base ring adjacent and surrounding the aperture; and   the at least one second face tile is a plurality of tiles that forms a substantially continuous wear surface on the front face of the base ring surrounding the front face tiles.   
   
   
       19 . A pump assembly for moving abrasive slurries, the pump assembly comprising:
 a pair of slurry conduits, each conduit having a circular opening;   a transfer conduit having a circular opening, the opening of the transfer conduit being movable between the openings of each of the pair of conduits to establish fluid communication between one of the slurry conduits and the transfer conduit; and   a seal ring associated with at least one of the openings in the slurry and transfer conduits, the seal ring including:
 a base ring formed of a fracture-tough metal, the base ring having opposing front and rear faces; 
 a circular opening extending through the base ring from the front face to the rear face, the aperture having an inner surface; 
 a plurality of inner-surface tiles formed of a hard metal and secured to the inner surface of the aperture to define a substantially continuous wear-resistant inner surface; 
 a plurality of inner face tiles formed of a hard metal and secured to the front face of the base ring adjacent the circular opening to define a substantially continuous wear-resistant surface surrounding the circular opening of the base ring; and 
 a plurality of outer face tiles formed of hard metal and secured to the front face of the base ring and spaced-apart from the aperture, the outer face tile being harder than the fracture-tough metal, the inner-surface tile being harder than the outer face tile, and the inner face tile being harder than the inner-surface tile. 
   
   
   
       20 . The pump assembly according to  claim 19 , wherein the fracture-tough metal is steel and the hard metal is tungsten carbide. 
   
   
       21 . The pump assembly according to  claim 19 , wherein the tiles are secured to the base ring by brazing.