Wellbore Conditioning System

Abstract

A wellbore conditioning system is disclosed. The system comprises at least one shaft and at least two eccentric unilateral reamers, wherein the unilateral reamers are positioned at a predetermined distance from each other and the unilateral reamers are positioned at a predetermined rotational angle from each other.

1 .- 20 . (canceled) 
     
     
         21 . An apparatus for use on a drill string for increasing the drift diameter of a well bore during drilling, comprising:
 at least one eccentric reamer positioned on the drill string, wherein each reamer has a plurality of cutting blades extending a distance radially outwardly from the outer surface of the reamer, wherein a first cutting blade extends a first distance and, in an order counter to the direction of rotation, each additional cutting blade extends an equal or greater distance than the preceding cutting blade, and the plurality of blades defining a curved cutting area extending approximately 50% or less of the circumference of each reamer.   
     
     
         22 . The apparatus of  claim 21 , further comprising grooves disposed between the cutting blades. 
     
     
         23 . The apparatus of  claim 21 , wherein each set of cutting blades is arranged along a spiral path along the surface of the associated reamer. 
     
     
         24 . The apparatus of  claim 21 , further comprising an array of two or more cutting teeth extending from each of the cutting blades and tangentially to each reamer. 
     
     
         25 . The apparatus of  claim 24 , wherein the teeth of each of the plurality of cutting blades of each reamer are offset from the teeth of the adjacent cutting blades. 
     
     
         26 . The apparatus of  claim 24 , wherein each tooth is comprised of carbide or diamond. 
     
     
         27 . The apparatus of  claim 24 , wherein the teeth face the direction of rotation. 
     
     
         28 . The apparatus of  claim 21 , further comprising a coupling adapted to receive a bottom hole assembly. 
     
     
         29 . The apparatus of  claim 21 , wherein the apparatus is positioned behind a drill bit. 
     
     
         30 . The apparatus of  claim 29 , wherein the apparatus is positioned at least 100 feet behind the drill bit. 
     
     
         31 . The apparatus of  claim 24 , wherein the teeth of each of the plurality of cutting blades are longitudinally overlapping from the teeth of the adjacent cutting blades. 
     
     
         32 . A well bore drilling device, comprising:
 a drill string;   a drill bit positioned at the end of the drill string; and   at least one eccentric reamer positioned on the drill string, wherein each reamer has a plurality of cutting blades extending a distance radially outwardly from the outer surface of the reamer, wherein a first cutting blade extends a first distance and, in an order counter to the direction of rotation, each additional cutting blade extends an equal or greater distance than the preceding cutting blade, and the plurality of blades defining a curved cutting area extending approximately 50% or less of the circumference of each reamer.   
     
     
         33 . The device of  claim 32 , further comprising grooves disposed between the cutting blades. 
     
     
         34 . The device of  claim 32 , wherein each set of cutting blades is arranged along a spiral path along the surface of the associated reamer. 
     
     
         35 . The device of  claim 32 , further comprising an array of two or more cutting teeth extending from each of the cutting blades and tangentially to each reamer. 
     
     
         36 . The apparatus of  claim 35 , wherein the teeth of each of the plurality of cutting blades of each reamer are offset from the teeth of the adjacent cutting blades. 
     
     
         37 . The apparatus of  claim 35 , wherein each tooth is comprised of carbide or diamond. 
     
     
         38 . The apparatus of  claim 35 , wherein the teeth face the direction of rotation. 
     
     
         39 . The apparatus of  claim 32 , wherein the pair of similar eccentric reamers are positioned at least 100 feet behind the drill bit. 
     
     
         40 . The apparatus of  claim 35 , wherein the teeth of each of the plurality of cutting blades are longitudinally overlapping from the teeth of the adjacent cutting blades. 
     
     
         41 . An apparatus for use on a drill string for increasing the drift diameter of a well bore during drilling, comprising:
 a pair of similar eccentric reamers positioned opposingly on the drill string, wherein each reamer has a plurality of cutting blades extending a distance radially outwardly from the outer surface of the reamer, wherein a first cutting blade extends a first distance and, in an order counter to the direction of rotation, each additional cutting blade extends an equal or greater distance than the preceding cutting blade, and the plurality of blades defining a curved cutting area extending approximately 50% or less of the circumference of each reamer.   
     
     
         42 . The apparatus of  claim 41 , further comprising grooves disposed between the cutting blades. 
     
     
         43 . The apparatus of  claim 41 , wherein each set of cutting blades is arranged along a spiral path along the surface of the associated reamer. 
     
     
         44 . The apparatus of  claim 41 , further comprising an array of two or more cutting teeth extending from each of the cutting blades and tangentially to each reamer. 
     
     
         45 . The apparatus of  claim 44 , wherein the teeth of each of the plurality of cutting blades of each reamer are offset from the teeth of the adjacent cutting blades. 
     
     
         46 . The apparatus of  claim 44 , wherein each tooth is comprised of carbide or diamond. 
     
     
         47 . The apparatus of  claim 44 , wherein the teeth face the direction of rotation. 
     
     
         48 . The apparatus of  claim 41 , further comprising a coupling adapted to receive a bottom hole assembly. 
     
     
         49 . The apparatus of  claim 41 , wherein the apparatus is positioned behind a drill bit. 
     
     
         50 . The apparatus of  claim 49 , wherein the apparatus is positioned at least 100 feet behind the drill bit. 
     
     
         51 . The apparatus of  claim 44 , wherein the teeth of each of the plurality of cutting blades are longitudinally overlapping from the teeth of the adjacent cutting blades. 
     
     
         52 . A well bore drilling device, comprising:
 a drill string;   a drill bit positioned at the end of the drill string; and   a pair of similar eccentric reamers positioned opposingly on the drill string, wherein each reamer has a plurality of cutting blades extending a distance radially outwardly from the outer surface of the reamer, wherein a first cutting blade extends a first distance and, in an order counter to the direction of rotation, each additional cutting blade extends an equal or greater distance than the preceding cutting blade, and the plurality of blades defining a curved cutting area extending approximately 50% or less of the circumference of each reamer.   
     
     
         53 . The device of  claim 52 , further comprising grooves disposed between the cutting blades. 
     
     
         54 . The device of  claim 52 , wherein each set of cutting blades is arranged along a spiral path along the surface of the associated reamer. 
     
     
         55 . The device of  claim 52 , further comprising an array of two or more cutting teeth extending from each of the cutting blades and tangentially to each reamer. 
     
     
         56 . The apparatus of  claim 55 , wherein the teeth of each of the plurality of cutting blades of each reamer are offset from the teeth of the adjacent cutting blades. 
     
     
         57 . The apparatus of  claim 55 , wherein each tooth is comprised of carbide or diamond. 
     
     
         58 . The apparatus of  claim 55 , wherein the teeth face the direction of rotation. 
     
     
         59 . The apparatus of  claim 52 , wherein the pair of similar eccentric reamers are positioned at least 100 feet behind the drill bit. 
     
     
         60 . The apparatus of  claim 55 , wherein the teeth of each of the plurality of cutting blades are longitudinally overlapping from the teeth of the adjacent cutting blades.