Method and apparatus for shaping a well hole

Abstract

A method of shaping a wellbore comprising attaching a drilling apparatus to a drill string, which has a side cutting sub-assembly with both cutting and gauging surfaces; a fluid circulating sub-assembly which has nozzles directing fluid up the wellbore and past the cutting surfaces; and a bullnose assembly with forward pointing nozzles and a bullnosed front end to prevent catching in ledges of a rough drilled wellbore. The drilling apparatus is then passed through the wellbore such that the side cutting sub shears arch wellbore walls of dog legs to ease the turns and smooth the bore wall in preparation for running liner/casing or other down hole assemblies which previously may have had difficulty going in hole.

What is claimed is: 
     
         1 . An apparatus for shaping of a wellbore comprising:
 a tubular shaped main body ( 221 ); and   a side cutting assembly ( 220 )
 having a plurality of cutting surfaces ( 226 ) arranged around the body's ( 220 ) outer circumference. 
   
     
     
         2 . An apparatus for shaping of a wellbore as described in  claim 1  wherein the side cutting assembly ( 220 ) further comprises a plurality of gauging surfaces ( 225 ) arranged around the body's ( 220 ) outer circumference. 
     
     
         3 . An apparatus for shaping of a wellbore as described in  claim 2  wherein the cutting surfaces ( 226 ) and gauging surfaces ( 225 ) are alternately grouped ( 222 ) in alignments running longitudinally. 
     
     
         4 . An apparatus for shaping of a wellbore as described in  claim 3  wherein flow paths ( 223 ) are longitudinally arranged between the alignments ( 222 ) of cutting ( 226 ) and gauging surfaces ( 225 ). 
     
     
         5 . An apparatus for shaping of a wellbore as described in  claim 4  wherein cutting channels ( 227 ) pass between the cutting ( 226 ) and gauging surfaces ( 225 ) running from one flow path ( 223 ) to another. 
     
     
         6 . An apparatus for shaping of a wellbore as described in  claim 1  wherein the cutting surfaces ( 226 ) are Polycrystalline Diamond Compact (PDC). 
     
     
         7 . An apparatus for shaping of a wellbore as described in  claim 2  wherein the gauging surfaces ( 225 ) are Diamond Domes (DD). 
     
     
         8 . An apparatus for shaping of a wellbore, as described in  claim 1  further comprising:
 a closed lower end ( 288 ); 
 wherein the closed lower end ( 288 ) has substantially rounded edges ( 285 ) forming a bullnosed shape ( 280 ). 
 
     
     
         9 . An apparatus for shaping of a wellbore, as described in  claim 8  further comprising:
 a plurality of nozzles ( 255 ) passing through the walls of the tubular shaped body ( 221 ) for directing fluid like substances from the center cavity ( 210 ) to the outside of a tubular shaped main body ( 221 ). 
 
     
     
         10 . An apparatus for shaping of a wellbore, as described in  claim 9  wherein the nozzles ( 255 ) are configurable to adjust the Total Flow Area (TFA). 
     
     
         11 . An apparatus for shaping of a wellbore, as described in  claim 10  wherein
 a plurality of the nozzles ( 255 ) are below the side cutting assembly ( 220 ); and 
 said plurality of nozzles ( 255 ) are angled to direct flow up past the side cutting assembly ( 220 ). 
 
     
     
         12 . An apparatus for shaping of a wellbore, as described in  claim 11  wherein the plurality of nozzles ( 255 ) are angled to direct flow up are in a separatable sub-assembly. 
     
     
         13 . An apparatus for shaping of a wellbore, as described in  claim 10  wherein
 a plurality of the nozzles ( 275 ) are located near or within the bullnose ( 280 ) end of the main body ( 200 ) and oriented to direct flow ahead of the apparatus ( 200 ) down the wellbore ( 150 ). 
 
     
     
         14 . An apparatus for shaping of a wellbore, as described in  claim 13  wherein the nozzles ( 275 ) are configurable to adjust the Total Flow Area (TFA). 
     
     
         15 . A method of shaping a wellbore comprising:
 preparing an wellbore for operations;   attaching a drilling apparatus ( 200 ) to a drill string ( 110 );
 said drilling apparatus ( 200 ) comprising:
 a side cutting sub-assembly ( 220 ) having
 a plurality of cutting surfaces ( 226 ): 
 flow paths ( 223 ) longitudinally between the cutting surfaces ( 226 ); and 
 cutting channels ( 227 ) between the cutting surfaces ( 226 ) running between flow paths ( 223 ); 
 
 a bullnose sub-assembly ( 270 ). 
 
   
     
     
         16 . A method of shaping a wellbore, as described in  claim 15 , further comprising:
 passing the drilling apparatus ( 200 ) into an irregularly shaped section ( 155 ) of a wellbore ( 150 ) such that the bullnose ( 280 ) forces the side cutter ( 220 ) into the side of the irregularly shaped section ( 155 ) causing the side cutting structures ( 226  &  225 ) to remove material ( 450 ) from the wall of the section ( 155 ).   
     
     
         17 . A method of shaping a wellbore, as described in  claim 15 , further comprising: passing the drilling apparatus ( 200 ) through an irregularly shaped section ( 155 ) of a wellbore ( 150 ) such that the drill string ( 110 ) forces the side cutter ( 220 ) into the side of the irregularly shaped section ( 155 ) causing the side cutting structures ( 225  &  226 ) to remove material ( 450 ) from the wall of the section ( 155 ). 
     
     
         18 . The method of shaping the wellbore as described in  claim 15  further comprising:
 attaching a drilling apparatus ( 200 ) to a drill string ( 110 ) which further comprises:
 a plurality of gauging surfaces ( 225 ), 
 
 using gauging surfaces ( 225 ) to avoid aggressive cutting of the wellbore walls. 
 
     
     
         19 . The method of shaping the wellbore as described in  claim 15  further comprising:
 attaching a drilling apparatus ( 200 ) to a drill string ( 110 ) which further comprises:
 an up flow nozzle sub-assembly ( 250 ); and 
 
 directing up flow nozzle's ( 255 ) total flow area to clear cuttings ( 450 ) from the side cutting assembly ( 220 ) during cutting operations. 
 
     
     
         20 . The method of shaping the wellbore as described in  claim 15  wherein preparing the wellbore for operations further comprises:
 inserting a circulating drilling apparatus ( 250 ) into the wellbore; 
 rotating the circulating drilling apparatus ( 250 ) into the wellbore; 
 running fluid through the circulating drilling apparatus ( 250 ) in the wellbore; and 
 washing existing cuttings ( 450 ) from the well bore ( 150 ).