Cutter Pocket Inserts

Abstract

A method for optimizing drill bit design and an optimized drill bit for drilling a well in an earth formation, wherein, in one embodiment, the optimized drill bit comprises a bit body with a plurality blades spaced along the bit body, each blade having a curved outer edge, a substantially flat forward face, and a number of insert pockets milled into each blade. A cutter insert is preferably secured into each insert pocket. The inserts are selected to give a desired cutter orientation, which is preferably independent of the orientation of the insert. Finally, a cutter is preferably secured at least partially within each cutter insert. The insert pockets may be formed by a cylindrical flat ended mill oriented substantially orthogonal to an outer edge of the blade, thereby creating the insert pockets with two substantially flat sidewalls, a curved endwall, and a substantially flat bottom.

1 . A method of optimizing a drill bit, such as for drilling a well into an earth formation, the method comprising the steps of:
 producing a bit body having a number of blades, each blade having at least one insert pocket formed therein;   selecting a cutter insert having a cutter pocket to give a desired orientation to a cutter;   securing the insert at least partially within the insert pocket; and   securing the cutter at least partially within the cutter pocket of the insert.   
   
   
       2 . The method at set forth in  claim 1 , wherein the insert pocket comprises two sidewalls substantially parallel to each other and a substantially flat bottom substantially perpendicular to the sidewalls. 
   
   
       3 . The method at set forth in  claim 1 , wherein the insert pocket comprises a flat bottom substantially perpendicular to a face of the blade. 
   
   
       4 . The method at set forth in  claim 1 , wherein the insert is selected from a plurality of inserts, each insert potentially providing a different orientation to the cutter. 
   
   
       5 . The method at set forth in  claim 1 , wherein an orientation of the insert is independent of the orientation of the cutter, such that the orientation of the cutter pocket within the insert provides the orientation of the cutter. 
   
   
       6 . The method at set forth in  claim 1 , wherein the insert is welded to the bit body. 
   
   
       7 . The method at set forth in  claim 1 , wherein the cutter is brazed to the insert. 
   
   
       8 . The method at set forth in  claim 1 , wherein the orientation comprises a back rake. 
   
   
       9 . The method at set forth in  claim 1 , wherein the orientation comprises a side rake. 
   
   
       10 . The method at set forth in  claim 1 , wherein the orientation comprises a cutter exposure. 
   
   
       11 . A method of optimizing a drill bit, such as for drilling a well into an earth formation, the method comprising the steps of:
 producing a bit body having a number of blades;   milling a number of insert pockets into each blade using a cylindrical flat ended mill, each insert pocket having an insert orientation;   selecting, for each insert pocket, a cutter insert to give a desired cutter orientation, the cutter orientation being independent of the insert orientation;   securing, for each insert pocket, the selected insert within the insert pocket; and   securing a cutter at least partially within each cutter insert.   
   
   
       12 . The method at set forth in  claim 11 , wherein the insert pocket comprises two sidewalls substantially parallel to each other and a flat bottom substantially perpendicular to the sidewalls and substantially perpendicular to a face of the blade. 
   
   
       13 . The method at set forth in  claim 11 , wherein each insert is selected from a plurality of inserts, each insert potentially providing a different cutter orientation. 
   
   
       14 . The method at set forth in  claim 13 , wherein the different cutter orientations potentially provided by the plurality of inserts comprise different back rakes, side rakes and exposures. 
   
   
       15 . The method at set forth in  claim 11 , wherein the cutter orientation comprises a back rake. 
   
   
       16 . The method at set forth in  claim 11 , wherein the cutter orientation comprises a side rake. 
   
   
       17 . The method at set forth in  claim 11 , wherein the cutter orientation comprises a cutter exposure. 
   
   
       18 . The method at set forth in  claim 11 , wherein, during the milling step, the mill is oriented substantially orthogonal to an outer edge of the blade. 
   
   
       19 . An optimized drill bit, such as for drilling a well into an earth formation, the drill bit comprising:
 a bit body having a number of blades;   a number of insert pockets milled into each blade, each insert pocket having an insert orientation;   a cutter insert welded into each insert pocket, the insert selected to give a desired cutter orientation, the cutter orientation being independent of the insert orientation; and   a cutter brazed at least partially within each cutter insert.   
   
   
       20 . The drill bit as set forth in  claim 19 , wherein the insert pockets are formed by a cylindrical flat ended mill oriented substantially orthogonal to an outer edge of the blade, such that the insert pocket comprises two sidewalls substantially parallel to each other and a flat bottom substantially perpendicular to the sidewalls and substantially perpendicular to a face of the blade.