Method and apparatus for reaming well bore surfaces nearer the center of drift

Abstract

A well bore reaming device and method are disclosed. The device includes a drill string, a bottom eccentric reamer coupled to the drill string, and a top eccentric reamer coupled to the drill string, wherein the bottom and top eccentric reamers have a prearranged spacing and orientation.

1 . A well bore reaming device, comprising:
 a drill string;   a bit coupled to the drill string;   a bottom hole assembly coupled to the drill string;   a bottom eccentric reamer coupled to the drill string; and   a top eccentric reamer coupled to the drill string;   wherein the bottom and top eccentric reamers are diametrically opposed on the drill string.   
     
     
         2 . The well bore reaming device of  claim 1 , further comprising cutting elements coupled to the top eccentric reamer and to the bottom eccentric reamer. 
     
     
         3 . The well bore reaming device of  claim 2 , wherein the cutting elements of the bottom eccentric reamer have a prearranged orientation with respect to the orientation of the cutting elements coupled to the top eccentric reamer. 
     
     
         4 . The well bore reaming device of  claim 2 , wherein each eccentric reamer comprises multiple sets of cutting elements. 
     
     
         5 . The well bore reaming device of  claim 4 , wherein each set of cutting elements are arranged along a spiral path along the surface of each eccentric reamer. 
     
     
         6 . The well bore reaming device of  claim 4 , further comprising a flow area adjacent to each set of cutting elements. 
     
     
         7 . The well bore reaming device of  claim 1 , wherein the bottom eccentric reamer and the top eccentric reamer are spaced at a prearranged position. 
     
     
         8 . The well bore reaming device of  claim 1 , wherein the outermost radius of the bottom and top eccentric reamers is less than the innermost radius of the well bore and casing. 
     
     
         9 . The well bore reaming device of  claim 1 , wherein the bottom eccentric reamer is identical to the top eccentric reamer. 
     
     
         10 . A method of reaming a well bore, comprising:
 providing a drill string;   providing drill bit coupled to the drill string;   providing a bottom hole assembly coupled to the drill string;   providing bottom eccentric reamer coupled to the drill string;   providing top eccentric reamer coupled to the drill string;   positioning the top and bottom eccentric reamers at diametrically opposed positions on the drill string; and   rotating the drill string in the well bore.   
     
     
         11 . The method of  claim 10 , further comprising coupling cutting elements to the top eccentric reamer and to the bottom eccentric reamer. 
     
     
         12 . The method of  claim 11 , wherein the cutting elements coupled to the bottom eccentric reamer have a prearranged orientation with respect to the orientation of the cutting elements coupled to the top eccentric reamer. 
     
     
         13 . The method of  claim 11 , further comprising providing each eccentric reamer with multiple sets of cutting elements. 
     
     
         14 . The method of  claim 13 , further comprising arranging each set of cutting elements along a spiral path along the surface of each eccentric reamer. 
     
     
         15 . The method of  claim 13 , further comprising providing a flow area adjacent to each set of cutting elements. 
     
     
         16 . The method of  claim 10 , further comprising spacing the bottom eccentric reamer and the top eccentric reamer at a prearranged spacing and orientation. 
     
     
         17 . The method of  claim 10 , wherein the outermost radius of the bottom and top eccentric reamers is less than the innermost radius of the well bore and casing. 
     
     
         18 . The method of  claim 10 , wherein the first eccentric reamer is identical to the second eccentric reamer.