Flat and bevel chipbreaker insert

Abstract

A cutting insert for use on a metal cutting tool downhole in an oil or gas well, with at least one land on a leading edge of the insert, and at least one bevel surface angled relative to the axis of the insert and rising above the adjacent land in the direction of travel of the insert. Multiple bevels and lands can be used on each insert, and multiple inserts can be used on each tool.

1 . A metal cutting insert for use on a downhole tool in an oil or gas well, said insert comprising: 
 a solid body, said body having an axis;    a rear face on said body, for mounting said body to a downhole type metal cutting tool;    a front face on said body, opposite said rear face, for presentation to a downhole metal object to be cut;    a plurality of lands formed on said front face of said body, each said land being substantially orthogonal to said axis of said body; and    a plurality of bevels formed on said front face of said body, each said bevel being angled relative to said axis of said body, forward of an adjacent said land.    
   
   
       2 . The metal cutting insert recited in  claim 1 , wherein each said land is angled no less than 75 degrees relative to said axis of said body.  
   
   
       3 . The metal cutting insert recited in  claim 1 , wherein each said bevel is angled between 20 degrees and 70 degrees relative to said axis of said body.  
   
   
       4 . The metal cutting insert recited in  claim 1 , wherein a first said land is formed at an edge of said front face.  
   
   
       5 . The metal cutting insert recited in  claim 4 , wherein a first said bevel is formed adjacent to said first land.  
   
   
       6 . The metal cutting insert recited in  claim 5 , wherein said plurality of lands and said plurality of bevels are formed at alternating locations across said front face.  
   
   
       7 . The metal cutting insert recited in  claim 1 , wherein: 
 each said land is a substantially planar rectilinear surface; and    each said bevel is a substantially planar rectilinear surface.    
   
   
       8 . The metal cutting insert recited in  claim 7 , wherein said insert body is a substantially rectilinear solid.  
   
   
       9 . The metal cutting insert recited in  claim 1 , wherein: 
 each said land is a substantially planar annular surface; and    each said bevel is a substantially frusto-conical surface.    
   
   
       10 . The metal cutting insert recited in  claim 9 , wherein said insert body is substantially cylindrical.  
   
   
       11 . A downhole metal cutting tool for gas or oil wells, comprising: 
 a tool body adapted for lowering into an oil or gas well to rotatingly cut a downhole metal object;    at least one metal cutting insert for mounting on said downhole tool body, said at least one insert having a solid body with an axis;    a front face on said at least one insert body, for presentation to said downhole metal object;    at least one land formed on said front face of said at least one insert body, said at least one land being substantially orthogonal to said axis of said at least one insert body; and    at least one bevel formed on said front face of said at least one insert body, said at least one bevel being angled above said at least one land, relative to said axis of said at least one insert body.    
   
   
       12 . The downhole metal cutting tool recited in  claim 11 , further comprising: 
 a plurality of said lands; and    a plurality of said bevels;    wherein said plurality of lands and said plurality of bevels are formed at alternating locations across said front face of said at least one insert body.    
   
   
       13 . The downhole metal cutting tool recited in  claim 12 , wherein: 
 a first said land is formed at an edge of said front face of said at least one insert body; and    a first said bevel is formed adjacent to said first land.    
   
   
       14 . The downhole metal cutting tool recited in  claim 12 , wherein each said land is angled no less than 75 degrees relative to said axis of said at least one insert body.  
   
   
       15 . The downhole metal cutting tool recited in  claim 12 , wherein each said bevel is angled between 20 degrees and 70 degrees relative to said axis of said at least one insert body.  
   
   
       16 . The downhole metal cutting tool recited in  claim 12 , wherein: 
 each said land is a substantially planar rectilinear surface; and    each said bevel is a substantially planar rectilinear surface.    
   
   
       17 . The downhole metal cutting tool recited in  claim 16 , wherein said insert body is a substantially rectilinear solid.  
   
   
       18 . The downhole metal cutting tool recited in  claim 12 , wherein: 
 each said land is a substantially planar annular surface; and    each said bevel is a substantially frusto-conical surface.    
   
   
       19 . The downhole metal cutting tool recited in  claim 18 , wherein said insert body is substantially cylindrical.