Tapered reamer bit

Abstract

A tapered reamer bit which achieves a reaming function at least in part by tension fracturing a geographic formation such that the resulting fragments of the formation are forced upward and/or backward and without relying on multiple rotatably positionable cylinders disposed on the reamer bit. Because of the tooth placement of the tapered reamer bit, a rotational force applied thereto results in a downward/forward force while reaming out a hole through a geographic formation.

1 . A tapered reamer bit comprising: 
 a tapered outer surface;    one or more teeth attached to said reamer bit at a pitch angle relative to a plane perpendicular to an axis of said reamer bit;    said teeth attached to said reamer bit at a tilt such that said teeth are disposed at an angle relative to a normal of said outer surface of said tapered reamer bit.    
   
   
       2 . The tapered reamer bit of  claim 1  wherein said pitch angle comprises an angle of about 1° to about 15°.  
   
   
       3 . The tapered reamer bit of  claim 2  wherein said pitch angle comprises an angle of about 3° to about 8°.  
   
   
       4 . The tapered reamer bit of  claim 1  wherein a plurality of said teeth comprise different pitch angles.  
   
   
       5 . The tapered reamer bit of  claim 4  wherein said pitch angles vary from about 3.6° to about 4° across a length of said tapered reamer bit.  
   
   
       6 . The tapered reamer bit of  claim 1  wherein said angle relative to a normal comprises an angle of about 5° to about 25°.  
   
   
       7 . The tapered reamer bit of  claim 6  wherein said angle relative to a normal comprises an angle of about 10° to about 20°.  
   
   
       8 . The tapered reamer bit of  claim 7  wherein said angle relative to a normal comprises an angle of about 15°.  
   
   
       9 . The tapered reamer bit of  claim 1  wherein one or more of said teeth comprise a groove axially disposed along a length thereof.  
   
   
       10 . The tapered reamer bit of  claim 1  wherein each of said teeth maintains a consistent distance from the other teeth when at rest and when in use.  
   
   
       11 . A self-advancing reamer bit comprising: 
 a single, continuous, outer surface with a plurality of teeth protruding therefrom;    said teeth disposed such that rotation of said reamer bit causes teeth to exert an upward force on a material to be reamed, thus resulting in a downward force exerted on said reamer bit.    
   
   
       12 . The tapered reamer bit of  claim 11  wherein said teeth protrude from said reamer bit at a pitch angle relative to a plane perpendicular to an axis of said reamer.  
   
   
       13 . The tapered reamer bit of  claim 12  wherein said pitch angle comprises an angle of about 1° to about 15°.  
   
   
       14 . The tapered reamer bit of  claim 13  wherein said pitch angle comprises an angle of about 3° to about 8°.  
   
   
       15 . The tapered reamer bit of  claim 12  wherein a plurality of said teeth comprise different pitch angles.  
   
   
       16 . The tapered reamer bit of  claim 15  wherein said pitch angles varies from about 3.6° to about 4° across a length of said tapered reamer bit.  
   
   
       17 . The tapered reamer bit of  claim 11  wherein said teeth are at an angle relative to a normal of said outer surface of said reamer bit.  
   
   
       18 . The tapered reamer bit of  claim 17  wherein said angle comprises an angle of about 5° to about 25°.  
   
   
       19 . The tapered reamer bit of  claim 17  wherein said angle relative to the normal comprises an angle of about 10° to about 20° 
   
   
       20 . The tapered reamer bit of  claim 19  wherein said angle relative to the normal comprises an angle of about 15°.  
   
   
       21 . A method for reaming a hole in a subsurface formation comprising: 
 rotating a reamer bit comprising a single, continuous outer surface with a plurality of teeth protruding therefrom; and    exerting an upward force on a subsurface formation with one or more of teeth until one or more fragments of the subsurface formation break free from the formation and are forced upwardly, thus producing a downward force on the reamer.    
   
   
       22 . The method of  claim 21  comprising maintaining a consistent distance between each of the teeth.  
   
   
       23 . The method of  claim 21  comprising disposing the teeth at a plurality of pitch angles relative to a plane that is perpendicular to the axis of the reamer.  
   
   
       24 . The method of  claim 21  composing disposing the teeth at one or more angles relative to a normal of the outer surface of the reamer bit.  
   
   
       25 . The method of  claim 23  wherein at least one of the pitch angles comprises an angle of about 1° to about 15°.  
   
   
       26 . The method of  claim 25  wherein at least one of the pitch angles comprises an angle of about 5° to about 25°.