Fluid end with curved internal cavity profile

Abstract

A fluid end assembly includes a fluid end and a plurality of valve assemblies each located within a cavity that has curved internal profiles. The curved internal profiles of the cavities are concaved outward. A plunger is included to provide variations in pressure within the fluid end so as to facilitate movement of the working fluid. A discharge plug is included in communication with the fluid end. The discharge plug may include a curved profile along an inner surface that corresponds with one of the cavities therein. A suction plug is releasably coupled to the fluid end and includes a curved profile along an inner surface. The suction plug also includes a recess for acceptance of a spring retainer. The spring retainer is included to support a suction valve assembly.

What is claimed is: 
     
         1 . A fluid end assembly, comprising:
 a fluid end;   a plunger for reciprocation through a plunger bore in the fluid end;   a suction valve located within a suction cavity in the fluid end, the suction cavity having a curved internal profile; and   a discharge valve located within a discharge cavity in the fluid end, the discharge cavity having a curved internal profile;   wherein the curved internal profiles of the suction cavity and the discharge cavity are concaved outward.   
     
     
         2 . The assembly of  claim 1 , wherein the plunger bore is radiused so as to open or expand away from the plunger adjacent to the suction cavity and the discharge cavity. 
     
     
         3 . The assembly of  claim 1 , wherein the plunger bore has a plurality of radiused curves, the plurality of radiused curves having at least two different curve diameters joined together tangentially and cause the diameter of the plunger bore to vary. 
     
     
         4 . The assembly of  claim 1 , wherein the suction cavity has a plurality of radiused curves joined together tangentially. 
     
     
         5 . The assembly of  claim 4 , wherein the plurality of radiused curves in the suction cavity each have a different curve diameter. 
     
     
         6 . The assembly of  claim 1 , wherein the discharge cavity has a plurality of radiused curves joined together tangentially. 
     
     
         7 . The assembly of  claim 6 , wherein the plurality of radiused curves in the discharge cavity each have a different curve diameter. 
     
     
         8 . The assembly of  claim 1 , further comprising:
 a suction plug releasably coupled to the fluid end and located linearly with the plunger, the suction plug including a curved profile along an inner surface.   
     
     
         9 . The assembly of  claim 8 , wherein the suction plug includes a recess along the inner surface, the recess being radiused adjacent the inner surface. 
     
     
         10 . The assembly of  claim 9 , further comprising:
 a spring retainer in communication with the suction valve, the spring retainer configured to pass into the recess.   
     
     
         11 . The assembly of  claim 8 , wherein the suction plug includes a mating surface and a seal groove, the seal groove located below the mating surface and includes a seal having a diameter, the mating surface configured to engage a corresponding mating surface of the fluid end upon installation; and
 wherein the diameter at the intersection of the suction plug mating surface and the seal groove is the same as the seal diameter to avoid extrusion gap.   
     
     
         12 . The assembly of  claim 11 , wherein a clearance gap is maintained between the suction plug and the fluid end above the mating surface. 
     
     
         13 . The assembly of  claim 1 , further comprising:
 a spring retainer in communication with the suction valve, the suction cavity including one or more parallel faces tangential to the curved profile of the suction cavity, the parallel faces configured to align and position the spring retainer.   
     
     
         14 . The assembly of  claim 1 , further comprising:
 a discharge plug in communication with both the discharge valve and the discharge cavity, the discharge valve and the discharge plug are on opposing ends of the discharge cavity.   
     
     
         15 . The assembly of  claim 14 , wherein the discharge plug includes a discharge plug curve profile adjacent the discharge cavity. 
     
     
         16 . The assembly of  claim 15 , wherein the curve of the discharge plug curve profile is configured to match that of the discharge cavity curved profile, such that the curved profile of the discharge cavity is continued along the discharge plug curve profile. 
     
     
         17 . The assembly of  claim 14 , wherein the discharge plug includes a mating surface and a seal groove, the seal groove located below the mating surface and includes a seal having a diameter, the mating surface configured to engage a corresponding mating surface of the fluid end upon installation; and
 wherein the diameter at the intersection of the discharge plug mating surface and the seal groove is the same as the seal diameter to avoid extrusion gap.   
     
     
         18 . The assembly of  claim 18 , wherein a clearance gap is maintained between the discharge plug and the fluid end above the mating surface. 
     
     
         19 . A fluid end assembly, comprising:
 a fluid end;   a plunger for reciprocation through a plunger bore in the fluid end;   a suction valve located within a suction cavity in the fluid end, the suction cavity having a curved internal profile;   a discharge valve located within a discharge cavity in the fluid end, the discharge cavity having a curved internal profile;   a discharge plug in communication with both the discharge valve and the discharge cavity, the discharge valve and the discharge plug are on opposing ends of the discharge cavity, the discharge plug includes a discharge plug curve profile adjacent the discharge cavity;   a suction plug releasably coupled to the fluid end and located linearly with the plunger, the suction plug including a curved profile along an inner surface, the suction plug includes a recess along the inner surface, the recess being radiused adjacent the inner surface; and   a spring retainer in communication with the suction valve, the spring retainer configured to pass into the recess of the suction plug;   wherein the curved internal profiles of the suction cavity and the discharge cavity are concaved outward.   
     
     
         20 . The assembly of  claim 19 , wherein the curve of the discharge plug curve profile is configured to match that of the discharge cavity curved profile, such that the curved profile of the discharge cavity is continued along the discharge plug curve profile.