Component of bottom hole assembly having upwardly-directed fluid cleaning flow and methods of using same

Abstract

A stabilizer, drill bit, or other component of a bottom hole assembly for use in drilling a borehole includes an elongate and generally cylindrical body, a flow bore in the body, a plurality of outwardly-extending blades, with a valley disposed between adjacent blades. A ring segment that is spaced from the body and extends across at least one valley to define a flow passage through which cuttings-laden drilling mud is conveyed with an upwardly-direct trajectory. The body includes a hole or passageway for conveying drilling mud from the flow bore to between the blades. The passageway terminates in an exit directed toward the flow passage so as to provide fresh drilling mud with a trajectory such that the fluid passes through the flow passage.

1 . A stabilizer for use in drilling a borehole, comprising:
 a generally cylindrical body having an inner wall defining a flow bore in said body;   a plurality of blades extending outwardly from said body;   a valley disposed between a pair of adjacent blades;   a ring segment spaced from said body and extending over said valley;   a flow passage between said ring segment and said body;   a hole in said body configured to convey drilling fluid from said flow bore to between said pair of blades.   
     
     
         2 . The stabilizer of  claim 1  wherein said hole comprises an entrance in said inner wall and an exit in said valley, said hole extending between said flow bore and said flow passage. 
     
     
         3 . The stabilizer of  claim 1  wherein said hole is configured to convey drilling fluid with a trajectory through at least a portion of said flow passage 
     
     
         4 . The stabilizer of  claim 2  wherein the hole extends at an obtuse angle to the direction of flow of drilling fluid through the flow bore. 
     
     
         5 . The stabilizer of  claim 1  wherein said exit of said hole is located beneath said ring segment. 
     
     
         6 . The stabilizer of  claim 1  further comprising a sleeve disposed in said hole, said sleeve lining at least a part of said hole. 
     
     
         7 . The stabilizer of  claim 3  wherein said hole comprises a nozzle having a nozzle bore through which drilling fluid is conveyed. 
     
     
         8 . The stabilizer of  claim 7  wherein said nozzle bore includes a fluid entry end having a first flow area and a fluid exit end having a second flow area smaller than said first flow area. 
     
     
         9 . The stabilizer of  claim 1 , wherein said body has a wall thickness that varies along the longitudinal length of said body and comprises a transition zone between a thick wall portion in said valley and a thin wall portion under said ring segment, wherein said hole is positioned in said transition zone. 
     
     
         10 . The stabilizer of  claim 1  wherein only one ring segment spans between adjacent blades. 
     
     
         11 . The stabilizer of  claim 1  wherein a ring segment is arranged between every adjacent blade forming a complete ring about said stabilizer. 
     
     
         12 . A drill bit for use in drilling a borehole, the drill bit comprising:
 a generally cylindrical bit body having an inner wall defining a flow bore for conveying drilling mud;   a pair of blades extending outwardly from said bit body;   a valley disposed between said pair of blades;   a ring segment spaced from said bit body and extending over said valley;   a flow passage between said bit body and said ring segment;   a hole in said body configured to convey drilling fluid from said flow bore to said flow passage.   
     
     
         13 . The drill bit of  claim 12  wherein said hole comprises an exit in said flow passage. 
     
     
         14 . The drill bit of  claim 12  wherein said wherein said exit is located beneath said ring segment. 
     
     
         15 . The drill bit of  claim 12  wherein said hole extends at an obtuse angle to the direction of flow of drilling fluid through said flow bore. 
     
     
         16 . The drill bit of  claim 15  wherein said obtuse angle is between 140 degrees and 170 degrees. 
     
     
         17 . The drill bit of  claim 12  wherein said exit is configured to convey drilling fluid with a trajectory passing through said flow passage. 
     
     
         18 . The drill bit of  claim 17  wherein said hole comprises a nozzle having a nozzle bore through which drilling fluid is conveyed. 
     
     
         19 . The drill bit of  claim 12  wherein said bit body has a wall thickness that varies along the longitudinal length of said body and comprises a transition zone between a thick wall portion in said valley and a thin wall portion under said ring segment, wherein said hole is disposed in said transition zone. 
     
     
         20 . Apparatus for use in drilling a borehole in earthen formations, comprising:
 an elongate body having an outer surface and an internal flow bore configured to convey drilling fluid longitudinally through said body;   at least a first pair of blades connected to said body and extending radially beyond said outer surface;   a valley between said pair of blades;   a ring segment spaced apart from said outer surface and connected to each of said first pair of blades, said ring segment bridging said valley;   a flow passage between said ring segment and said outer surface of said body;   a hole extending from said flow bore to said outer surface and configured to direct a portion that is less than all of the drilling fluid from said flow bore though an exit in the outer surface, and to impart a trajectory to said portion of drilling fluid such that it passes through said flow passage.   
     
     
         21 . The apparatus of  claim 20  wherein said body has a wall thickness that varies along the longitudinal length of said body and comprises a transition zone between a thick wall portion in said valley and a thin wall portion under said ring segment, wherein said hole is disposed in said transition zone. 
     
     
         22 . The apparatus of  claim 20  wherein said hole extends at an obtuse angle to the direction of flow of drilling fluid through said flow bore. 
     
     
         23 . The apparatus of  claim 22  wherein said exit is positioned beneath said ring segment.