Fluid End for a Pump

Abstract

A fluid end for a pump is described herein. The fluid end includes a suction end, a discharge end, and a plunger end. The fluid end defines a main chamber which when viewed in cross section has a substantially elliptical outer boundary. The fluid end can further include an access end.

What is claimed is: 
     
         1 . A fluid end for a positive displacement pump, the fluid end comprising:
 a) a suction end defining a suction bore extending therethrough, the suction end extending along a suction end centerline and further defining a suction end transition portion;   b) a discharge end defining a discharge bore extending therethrough, the discharge end extending along a discharge end centerline and further defining a discharge end transition portion; and   c) a plunger end defining a plunger bore extending therethrough, the plunger end extending along a plunger end centerline and further defining a plunger end transition portion;   wherein the fluid end defines a main chamber which when viewed in cross section has a substantially elliptical outer boundary; and wherein each transition portion places its respective bore in fluid communication with the main chamber.   
     
     
         2 . The fluid end of  claim 1  wherein the main chamber comprises a center point, the center point being distal from the one or more centerlines. 
     
     
         3 . The fluid end of  claim 2 , wherein the main chamber has a semi-major axis, a semi-minor axis, and a focal distance, wherein the center point of the main chamber is positioned from the one or more centerlines in a range that is the greater of (a) about 0% to about 50% of the focal distance, and (b) about 0% to 25% of the length of the semi-major axis. 
     
     
         4 . The fluid end of  claim 1  wherein all of the centerlines share a common intersection that is disposed in the main chamber. 
     
     
         5 . The fluid end of  claim 4  wherein the main chamber comprises a center point, the center point being distal from the common intersection. 
     
     
         6 . The fluid end of  claim 5 , wherein the main chamber has a semi-major axis, a semi-minor axis, and a focal distance, wherein the center point of the main chamber is positioned from the common intersection in a range that is the greater of (a) about 0% to about 50% of the focal distance, and (b) about 0% to 25% of the length of the semi-major axis. 
     
     
         7 . The fluid end of  claim 2  wherein the main chamber comprises an outer boundary which forms a substantially ellipsoid shape. 
     
     
         8 . The fluid end of  claim 5  wherein the main chamber comprises an outer boundary which forms a substantially ellipsoid shape. 
     
     
         9 . The fluid end of  claim 1  wherein the maximum von Mises stress of an internal surface of the fluid end is in a range of less than about 75,000 psi when the internal surface of the fluid end is subjected to about 15,000 psi hydrostatic pressure. 
     
     
         10 . The fluid end of  claim 2  wherein a planar cross section passing through the center point of the main chamber forms an ellipse on a surface of the planar cross section. 
     
     
         11 . The fluid end of  claim 1  wherein the suction end centerline is substantially coaxial with the discharge centerline. 
     
     
         12 . The fluid end of  claim 11  wherein the plunger end centerline is substantially perpendicular to the suction end centerline and the discharge end centerline. 
     
     
         13 . The fluid end of  claim 1  wherein when the plunger end centerline intersects with the suction end centerline at a bore intersection point, an angle is formed between the two centerlines that is greater than about 90 degrees. 
     
     
         14 . The fluid end of  claim 1  wherein when the plunger end centerline intersects with the discharge end centerline, an angle is formed between the two centerlines that is greater than about 90 degrees. 
     
     
         15 . The fluid end of  claim 1  further comprising an access end defining an access bore extending therethrough, the access end extending along an access end centerline and further defining an access end transition portion. 
     
     
         16 . The fluid end of  claim 1  wherein the main chamber is formed by multi-axis mill machining. 
     
     
         17 . The fluid end of  claim 1  wherein the main chamber is formed by electrical discharge machining. 
     
     
         18 . The fluid end of  claim 1  wherein the main chamber comprises at least one material selected from the group consisting of an investment casted material, a strength treated material, and a surface treated material. 
     
     
         19 . The fluid end of  claim 7  wherein the outer boundary of the main chamber is defined by an internal surface of the main chamber. 
     
     
         20 . The fluid end of  claim 8  wherein the outer boundary of the main chamber is defined by an internal surface of the main chamber.