Multi-Piece Fluid End

Abstract

A fluid end is formed from a first body attached to a separate second body. Each body includes an external surface. When the bodies are attached, their respective external surfaces are in flush engagement. A plurality of bores are formed in the second body that are alignable with a plurality of corresponding bores formed in the first body. The fluid end may be used with seals disposed within recesses within each bore to seal against corresponding sealing surfaces. Further, retaining closures may be bolted to the fluid end bodies, such that the closures have a threadless connection to the fluid end bodies. Various combinations of such components may be utilized.

1 . A fluid end assembly, comprising:
 a housing comprising one or more fluid end bodies, the housing having an external surface and an internal chamber;   a first bore formed in the housing and having first and second sections, each section independently interconnecting the internal chamber and the external surface;   a second bore formed in the housing, intersecting the first conduit and independently interconnecting the internal chamber and the external surface; and   an endless groove formed in the wall or walls defining one of the bores and extending concentrically around that conduit.   
     
     
         2 . The fluid end assembly of  claim 1  further comprising:
 a valve seat disposed within the first bore comprising:
 an annular body having a first end and a second end, in which:
 the first end defines a tapered exterior surface having a frusto-conical first taper conforming to a portion of the first bore; and 
 the second end defines an internally disposed strike face; and 
 
 an insert disposed within the second end of the body, in which the insert is harder than the body and in which a portion of the insert is integrated with the strike face. 
 
 
     
     
         3 . The fluid end assembly of  claim 2  further comprising:
 a component configured for removable installation within one of the bores; 
 a retainer element engagable with the component when the component is installed within one of the bores; and 
 a fastening system configured to releasably hold the retainer element against the component when the component is installed within the bore; 
 in which the bore has no internal threads formed within that portion that surrounds the component when the component is installed within the bore. 
 
     
     
         4 . The fluid end of  claim 3  in which the housing comprises:
 a first fluid end body, comprising:
 an external surface having a front side and an opposed back side; and 
 a plurality of bore pairs, each bore pair comprising one of the first bores and one of the second bores; and 
 
 a second fluid end body, formed as a different piece from the first fluid end body, and comprising:
 an external surface having a front side and an opposed back side; and 
 a plurality of bores extending through the second fluid end body, each bore terminating at an opening formed in the external surface, each opening alignable with a corresponding opening formed in the external surface of the first fluid end body; 
 
 in which the first fluid end body is attached to the second fluid end body such that the back side of the first fluid end body is held against the front side of the second fluid end body. 
 
     
     
         5 . A pump assembly comprising:
 a power end comprising a plurality of plungers; and   the fluid end of  claim 4 ;   in which the plurality of plungers are receivable within one of the plurality of bores of the second fluid end body.   
     
     
         6 . The fluid end of  claim 4  further comprising:
 a valve assembly disposed within one of the sections of the first bore, in which the first bore has a center axis and a tapered wall disposed at a non-zero angle relative to the center axis, the valve assembly comprising:
 a valve body having spaced inner and outer peripheries, the valve body characterized by a strike face having a shape complementary to the strike face of the valve seat, the valve body comprising:
 a first insert disposed at the outer periphery of the valve body strike face; and 
 a second insert disposed at the inner periphery of the valve body strike face; 
 wherein the first insert and second insert are each composed of a different material than the valve body strike face. 
 
 
 
     
     
         7 . The fluid end of  claim 1  in which the housing comprises:
 a first fluid end body, comprising:
 an external surface having a front side and an opposed back side; and 
 a plurality of bore pairs, each bore pair comprising one of the first bores and one of the second bores; and 
 
 a second fluid end body, formed as a different piece from the first fluid end body, and comprising:
 an external surface having a front side and an opposed back side; and 
 a plurality of bores extending through the second fluid end body, each bore terminating at an opening formed in the external surface, each opening alignable with a corresponding opening formed in the external surface of the first fluid end body; 
 
 in which the first fluid end body is attached to the second fluid end body such that the back side of the first fluid end body is held against the front side of the second fluid end body. 
 
     
     
         8 . An apparatus, comprising:
 a first fluid end body, comprising:
 an external surface having a front side and an opposed back side; and 
 at least one bore pair, comprising:
 a first bore extending through the first body and terminating at an opening formed in the external surface; and 
 a second bore extending through the first fluid end body, intersecting the first bore, and terminating at an opening formed in the external surface; and 
 
   a second, flangeless fluid end body, formed as a different piece from the first fluid end body, and comprising:
 an external surface having a front side and an opposed back side; and 
 at least one bore extending through the second fluid end body and terminating at an opening formed in the external surface, the opening alignable with a corresponding opening formed in the external surface of the first fluid end body; and 
   an endless groove formed in the wall or walls defining one of the bores and extending concentrically around that bore;   a valve seat disposed within the first bore comprising:
 an annular body having a first end and a second end, in which:
 the first end defines a tapered exterior surface having a frusto-conical first taper conforming to a portion of first bore; and 
 the second end defines an internally disposed strike face; and 
 
 an insert disposed within the second end of the body, in which the insert is harder than the body and in which a portion of the insert is integrated with the strike face; 
   a valve body disposed within the first bore having a strike face complementary to the strike face of the valve seat;   a component configured for removable installation within one of the bores;   a retainer element engagable with the nut when the component is installed within one of the bores;   a fastening system configured to releasably hold the retainer element against the component when the component is installed within one of the bores; and   a seal disposed within the endless groove and contacting the component when the component is installed within one of the bores;   in which the bore has no internal threads formed within that portion that surrounds the component when the component is installed within the bore;   in which the first and second fluid end bodies are attached such that the front side of the second fluid end body engages the back side of the first fluid end body.   
     
     
         9 . A pump assembly comprising:
 a power end configured to reciprocate at least one plunger;   the apparatus of  claim 8  in which the at least one plunger extends partially within the second bore; and   at least one fastener to connect the power end and the apparatus.   
     
     
         10 . The apparatus of  claim 8  in which the first fluid end body is made of stainless steel. 
     
     
         11 .- 150 . (canceled)