Welded Downhole Components and Method of Forming Same

Abstract

Welded downhole tools and methods are provided. The downhole tool is deployable into a wellbore penetrating a subterranean formation. The downhole tool includes a first downhole component having a first mating feature on at least one end thereof and at least one second downhole component weldably connectable to the end of the first downhole component. The second downhole component has a second mating feature on an end thereof. The first and second mating features include at least one raised ridge for concentric self-alignment along a common axis with the other of the first and second mating features whereby, upon frictional engagement of the end of the first downhole component with the end of the second component under heat and pressure, a welded connection is formed therebetween.

What is claimed is: 
     
         1 . A downhole tool deployable into a wellbore penetrating a subterranean formation, the downhole tool comprising:
 a first downhole component having a first mating feature on at least one end thereof; and   at least one second downhole component having a second mating feature on an end thereof weldably connectable to the at least one end of the first downhole component;   wherein at least one of the first and second mating features comprises at least one raised ridge for concentric self-alignment along a common axis with the other of the first and second mating features whereby, upon frictional engagement of the end of the first downhole component with the end of the second component under heat and pressure, a welded connection is formed therebetween.   
     
     
         2 . The downhole tool of  claim 1 , wherein at least one of the first and second mating features comprises at least one channel for receiving the at least one raised ridge. 
     
     
         3 . The downhole tool of  claim 1 , wherein the first downhole component comprises a base pipe and the second downhole component comprises a pair of tool joints weldable to each end of the base pipe to form a drill pipe. 
     
     
         4 . The downhole tool of  claim 1 , wherein the first and second downhole components each comprise a pipe. 
     
     
         5 . The downhole tools of  claim 1 , wherein the first downhole component comprises a pipe and the second downhole component comprises a bar. 
     
     
         6 . The downhole tool of  claim 1 , wherein the first and second components are concentric along the common axis. 
     
     
         7 . The downhole tool of  claim 1 , wherein the first and second components are non-concentric along the common axis. 
     
     
         8 . The downhole tool of  claim 1 , wherein the first downhole component has the same outer diameter as the at least one second downhole component. 
     
     
         9 . The downhole tool of  claim 1 , wherein the first downhole component has a different outer diameter from the at least one second downhole component. 
     
     
         10 . The downhole tool of  claim 1 , wherein the at least one ridge is one of conical, rounded, and beveled. 
     
     
         11 . The downhole tool of  claim 1 , wherein the at least one channel is one of conical, rounded, and beveled. 
     
     
         12 . The downhole tool of  claim 1 , wherein the first and second mating features are complimentary. 
     
     
         13 . The downhole tool of  claim 1 , wherein the first and second mating features are non-complimentary. 
     
     
         14 . The downhole tool of  claim 1 , wherein the at least one end of the first downhole component and the end of the second downhole component each have a seating surface. 
     
     
         15 . The downhole tool of  claim 14 , wherein the seating surface is perpendicular to a longitudinal axis of the first and second downhole components. 
     
     
         16 . The downhole tool of  claim 1 , wherein the first downhole component is recessable a distance into the at least one second downhole component. 
     
     
         17 . The downhole tool of  claim 16 , wherein the second downhole component comprises a flange recessed a distance therein for receiving the first downhole component. 
     
     
         18 . The downhole tool of  claim 1 , further comprising a third downhole component positionable between the first and second downhole components. 
     
     
         19 . The downhole tool of  claim 18 , wherein the third downhole component comprises one of a ferrel, a sleeve, a disc, a mandrel and combinations thereof. 
     
     
         20 . The downhole tool of  claim 1 , wherein each of the first and second components are one of hollow, solid, and combinations thereof. 
     
     
         21 . A downhole tool deployable into a wellbore penetrating a subterranean formation, the downhole tool comprising:
 a first downhole component having a first mating feature on at least one end thereof;   at least one second downhole component having a second mating feature on an end thereof weldably connectable to the at least one end of the first downhole component; and   a third downhole component positionable between the first and second downhole components for concentric alignment therebetween along a common axis whereby, upon frictional engagement of the end of the first downhole component with the end of the second component under heat and pressure, a welded connection is formed therebetween.   
     
     
         22 . The downhole tool of  claim 21 , wherein the third downhole component is removable. 
     
     
         23 . The downhole tool of  claim 21 , wherein the third downhole component is consumed during welding. 
     
     
         24 . A method for welding a downhole tool deployable into a wellbore penetrating a subterranean formation, the method comprising:
 providing a first downhole component having a first mating feature on at least one end thereof and at least one second downhole component having a second mating feature on an end thereof weldably connectable to the at least one end of the first downhole component, the first and second mating features comprising at least one raised ridge;   concentrically self-aligning along a common axis the first and second mating features; and   forming a welded connection between the first downhole component and the second downhole component by frictionally engaging the at least one end of the first downhole component with the end of the at least one second component under heat and pressure.   
     
     
         25 . The method of  claim 24 , wherein the forming further comprises rotating the first component. 
     
     
         26 . The method of  claim 24 , wherein the forming further comprises maintaining the second component in a stationary position. 
     
     
         27 . The method of  claim 24 , wherein the matingly engaging comprises interfitting the first mating feature with the second mating feature. 
     
     
         28 . The method of  claim 24 , wherein the step of mating comprises self-aligning the first mating feature with the second mating feature. 
     
     
         29 . The method of  claim 24 , further comprising inserting at least one additional component between the first downhole component and the second downhole component. 
     
     
         30 . The method of  claim 29 , further comprising consuming the at least one additional component in the forming of a welded connection. 
     
     
         31 . The method of  claim 24 , further comprising consuming at least a portion of the first and second mating features in the forming of a welded connection. 
     
     
         32 . The method of  claim 24 , wherein the forming comprises one of friction welding, fusing and combinations thereof. 
     
     
         33 . The method of  claim 24 , wherein the first and second downhole components are fused together according to concentricity and angularity tolerances.