Downhole tool and uses thereof

Abstract

There is provided a downhole tool that can be used to grind down and remove scale and debris that has built up within a wellbore. The downhole tool has a drill bit that has an outer surface for engaging a wellbore and defines a bit bore. The drill bit has a first end defining a bit face and a second end adapted to engage a drive pipe. The drill bit also has a projection coupled to the outer surface of the drill bit, the projection being adapted to remove debris from a wellbore. In some cases, the projection comprises a plurality of projections. Generally, the scale and debris are at least partially removed from the wellbore when ground down by the downhole tool comprising the projection.

What is claimed is: 
     
         1 . A downhole tool, comprising:
 a drill bit,   the drill bit having an outer surface for engaging a wellbore and defining a bit bore,   the drill bit having a first end defining a leading face and a second end adapted to engage a drive pipe; and   a projection coupled to the outer surface of the drill bit, the projection being adapted to remove debris from the wellbore.   
     
     
         2 . The tool of  claim 1 , wherein the projection comprises a plurality of projections. 
     
     
         3 . The tool of  claim 2 , wherein each of the plurality of projections is circumferentially displaced relative to each other. 
     
     
         4 . The tool of  claim 3 , wherein each of the plurality of projections is longitudinally displaced relative to each other. 
     
     
         5 . The tool of  claim 4 , wherein each of the plurality of projections are circumferentially and longitudinally displaced relative to each other and spiral along the outer surface of the drill bit. 
     
     
         6 . The tool of  claim 5 , wherein the outer surface of the drill bit has a substantially frustoconical-shaped section proximal the first end, and a substantially cylinder-shaped section. 
     
     
         7 . The tool of  claim 6 , wherein the outer surface of the drill bit has a substantially cylinder-shaped section abutting the second end, and a substantially frustoconical-shaped section abutting the substantially cylinder-shaped section and terminating at the first end. 
     
     
         8 . The tool of  claim 7 , wherein the projection extends substantially perpendicular from the outer surface of the drill bit. 
     
     
         9 . The tool of  claim 8 , wherein the projection extends from the outer surface between about 1 mm and about 10 mm. 
     
     
         10 . The tool of  claim 9 , wherein at least one of the plurality of projections extends beyond an outer diameter of the cylinder-shaped section, by an undercut height. 
     
     
         11 . The tool of  claim 10 , wherein the undercut height is a maximum of 10 mm. 
     
     
         12 . The tool of  claim 11 , wherein the undercut height is between about 2.5 mm and about 10 mm. 
     
     
         13 . The tool of  claim 1 , wherein the projection is substantially frustoconical-shaped. 
     
     
         14 . The tool of  claim 1 , wherein the projection is substantially shaped as a cone tip, a wedge-shape, a wedge-tip, a random clustering or a combination thereof. 
     
     
         15 . The tool of  claim 1 , wherein the projection is composed of one or more of substantially tungsten carbide, hardened metal, carbon steel or stainless steel. 
     
     
         16 . The tool of  claim 6 , wherein the projection is coupled to the substantially frustoconical-shaped section of the outer surface of the drill bit. 
     
     
         17 . The tool of  claim 7 , wherein the projection is coupled to the substantially frustoconical-shaped section of the outer surface of the drill bit. 
     
     
         18 . The tool of  claim 1 , wherein the projection is integral with the outer surface of the drill bit. 
     
     
         19 . The tool of  claim 1 , wherein the projection is pressed into the outer surface of the drill bit. 
     
     
         20 . The tool of  claim 1 , wherein the leading face comprises a plurality of pegs extending longitudinally from the leading face, adapted to facilitate drilling. 
     
     
         21 . The tool of  claim 1 , wherein the leading face is substantially a saw-tooth face. 
     
     
         22 . The tool of  claim 20 , wherein the leading face defines an elliptical plane having a pitch greater than 0 degrees. 
     
     
         23 . The tool of  claim 21 , wherein the leading face defines an elliptical plane having a pitch greater than 0 degrees. 
     
     
         24 . The tool of  claim 22 , wherein the pitch is between about 15 degrees and about 30 degrees. 
     
     
         25 . The tool of  claim 24 , wherein the pitch is about 24 degrees. 
     
     
         26 . The tool of  claim 20 , wherein at least a portion of the leading face is angled at a face angle. 
     
     
         27 . The tool of  claim 21 , wherein at least a portion of the leading face is angled at a face angle. 
     
     
         28 . The tool of  claim 26 , wherein the face angle is greater than 0 degrees. 
     
     
         29 . The tool of  claim 28 , wherein the face angle is between about 15 degrees and about 30 degrees. 
     
     
         30 . The tool of  claim 29 , wherein the face angle is about 24 degrees. 
     
     
         31 . The tool of  claim 6 , wherein the projection comprises a tungsten carbide coating providing a plurality of tungsten carbide clusters (clusterite) spaced about the frustoconical-shaped section. 
     
     
         32 . The tool of  claim 6 , wherein the frustoconical-shaped section comprises a taper. 
     
     
         33 . The tool of  claim 32 , wherein the taper is between about 2 degrees and about 8 degrees. 
     
     
         34 . The tool of  claim 33 , wherein the taper is about 5 degrees. 
     
     
         35 . In a downhole tool, comprising:
 a drill bit,   the drill bit having an outer surface for engaging a wellbore and defining a bit bore,   the drill bit having a first end defining a leading face and a second end adapted to engage a drive pipe; and   a projection coupled to the outer surface of the drill bit, the projection being adapted to remove debris from the wellbore, the use of the tool with an oil and gas well service rig or an oil and gas drilling rig.   
     
     
         36 . In a downhole tool, comprising:
 a drill bit,   the drill bit having an outer surface for engaging a wellbore and defining a bit bore,   the drill bit having a first end defining a leading face and a second end adapted to engage a drive pipe; and   a projection coupled to the outer surface of the drill bit, the projection being adapted to remove debris from the wellbore, the use of the tool with a tubular.   
     
     
         37 . In a downhole tool, comprising:
 a drill bit,   the drill bit having an outer surface for engaging a wellbore and defining a bit bore,   the drill bit having a first end defining a leading face and a second end adapted to engage a drive pipe; and   a projection coupled to the outer surface of the drill bit, the projection being adapted to remove debris from the wellbore, the use of the tool to remove debris from a wellbore.   
     
     
         38 . The use of  claim 37 , wherein the debris comprises hard scale. 
     
     
         39 . A method for servicing a well having a defined wellbore restricted by debris, comprising:
 inserting a clean-out string into the wellbore of the well, the clean-out string having a downhole tool coupled thereto the downhole tool, comprising:   a drill bit,   the drill bit having an outer surface for engaging a wellbore and defining a bit bore,   the drill bit having a first end defining a leading face and a second end adapted to engage a drive pipe;   a projection coupled to the outer surface of the drill bit, the projection being adapted to remove debris from the wellbore, the use of the tool; and   rotating the clean-out string to engage the downhole tool with the debris restricting the wellbore to remove the debris from the wellbore.   
     
     
         40 . The method of  claim 39 , further comprising circulating or reverse circulating a fluid through the well to carry the debris removed from the wellbore out of the well. 
     
     
         41 . The method of  claim 39 , wherein inserting the clean-out string into the wellbore comprises positioning the downhole tool within the wellbore at a point restricted by the debris. 
     
     
         42 . The method of  claim 39 , wherein engaging the downhole tool with the debris restricting the wellbore comprises rotating the downhole tool to engage a projection of the downhole tool with the debris to grind down or break apart the debris within the wellbore. 
     
     
         43 . The method of  claim 40 , wherein the fluid is a drilling fluid or a well-servicing fluid. 
     
     
         44 . The method of  claim 39 , wherein the well is a hydrocarbon recovery well or a water well. 
     
     
         45 . The method of  claim 39 , wherein the debris comprises hard scale or well-bottom debris or both.