Ultra-hard matrix reamer elements and methods

Abstract

Reamer elements for use with roller reamers and other types of reamer apparatuses, methods for forming such reamer elements, and methods for performing drilling operations using such reamer elements are disclosed. The reamer element includes a body formed from a matrix of tungsten carbide and at least one binding metal, and can include a tube disposed therethrough. In use, the body resists compressive forces, while the tube resists tensile forces, thereby preventing deformation of the reamer element. The matrix material of the body provides increased wear resistance, decreased magnetic interference, decreased yield, and increased weight on a drill bit when compared to conventional steel components.

1 . A reamer element for use within a drill string, the reamer element comprising:
 a body formed from a matrix of tungsten carbide and at least one binding metal, wherein the body comprises a longitudinal bore extending therethrough, and wherein the body resists compressive forces;   a tube disposed within the longitudinal bore, wherein the tube has a bore extending therethrough, and wherein the tube resists tensile forces; and   at least one reaming member disposed on the body for contacting and reaming a borehole wall during drilling operations.   
     
     
         2 . The reamer element of  claim 1 , wherein the tube comprises a metal tube having a length greater than the length of the body, thereby defining a first end and a second end, wherein the first end and the second end comprise connections for engaging adjacent components. 
     
     
         3 . The reamer of  claim 1 , wherein the reamer element comprises a roller element. 
     
     
         4 . A method for reaming a borehole, the method comprising the steps of:
 securing within a drill string a component comprising at least one reamer element having a body formed from a matrix of tungsten carbide and at least one binding metal, wherein the body comprises at least one reaming member extending therefrom, and a tube disposed within a longitudinal bore of the body, wherein the tube has a bore extending therethrough; and   performing an operation using the drill string, wherein said at least one reaming member contacts and reams a wall of a borehole, prevents lateral displacement of the drill string, or combinations thereof, wherein the body resists compressive forces and the tube resists tensile forces to prevent deformation of or damage to said at least one reamer.   
     
     
         5 . A method for forming a reamer element, the method comprising the steps of:
 providing particles of tungsten carbide into a mold comprising a first end, a second end, and a void having the shape of a reamer body with a longitudinal axis;   providing a spacer element into the void;   providing at least one binding metal in fluid communication with the mold;   heating said at least one binding metal, wherein said at least one binding metal is melted and flows into spaces between the particles of tungsten carbide to form a tungsten carbide matrix material;   permitting the tungsten carbide matrix material to cool to form a reamer body having a longitudinal bore with the spacer element therein, disposed within the void of the mold, wherein the reamer body is adapted to resist compressive forces;   removing the reamer body and the spacer element from the mold; and   providing a bore through the spacer element, wherein the spacer element is adapted to resist tensile forces.   
     
     
         6 . The method of  claim 5 , wherein the step of providing the particles of tungsten carbide into the mold comprises orienting the mold in a substantially vertical orientation such that the longitudinal axis is generally perpendicular to the earth's surface. 
     
     
         7 . The method of  claim 6 , wherein the step of providing the particles of tungsten carbide into the mold further comprises providing particles of tungsten carbide having a size configured to permit said at least one binding metal to flow from the first end of the mold to the second end. 
     
     
         8 . The method of  claim 5 , wherein the step of providing the particles of tungsten carbide into the mold comprises providing a homogeneous selection of particles of tungsten carbide into the mold. 
     
     
         9 . The method of  claim 5 , wherein the step of providing the spacer element into the void comprises providing a generally solid metal tube into the void, a filled metal tube into the void, or combinations thereof, and wherein a solid or filled interior of the solid metal tube, the filled metal tube, or combinations thereof resists deformation and weakening of the spacer element during the step of heating said at least one binding metal. 
     
     
         10 . The method of  claim 5 , wherein the step of providing the bore through the spacer element comprises forming a channel through a solid rod, removing a filling material from a hollow rod, or combinations thereof. 
     
     
         11 . The method of  claim 5 , further comprising the step of heat treating the reamer body after removing the reamer body from the mold. 
     
     
         12 . The method of  claim 5 , further comprising the steps of:
 providing a fusible material into a shell;   fusing the fusible material to form a solid insert within the shell; and   modifying the solid insert to form the mold comprising the shape usable to form a the reamer body.   
     
     
         13 . The method of  claim 12 , wherein the fusible material comprises foundry sand, a mixture of silica sand and a binder, a resin, a plasticizer, one or more polymers, or combinations thereof.