Method for pulling casing

Abstract

A method for pulling casing includes disposing a casing modification and pulling tool having an element therein that includes a profile, causing the element to move radially outwardly into contact with a casing disposed radially outwardly of the tool, deforming the casing with the element, applying a load to the casing, and failing the casing at the deformation. A system for pulling casing includes a casing modification tool having an element radially displaceable into a casing disposed radially outwardly thereof, the element configured to deform the casing, a casing spear operably connected to the casing modification tool, the spear configured to apply a load to the casing to fail the casing at the deformation. A borehole system includes a borehole in a subsurface formation, a casing disposed in the borehole, and a casing modification and pulling tool disposed in the casing.

What is claimed is: 
     
         1 . A method for pulling casing comprising:
 disposing a casing modification and pulling tool having an element therein that includes a profile;   causing the element to move radially outwardly into contact with a casing disposed radially outwardly of the tool;   deforming the casing with the element;   applying a load to the casing; and   failing the casing at the deformation.   
     
     
         2 . The method as claimed in  claim 1  further comprising setting a spear. 
     
     
         3 . The method as claimed in  claim 1  further comprising pulling the casing from a borehole in which the casing is disposed. 
     
     
         4 . The method as claimed in  claim 1  wherein the element is a punch. 
     
     
         5 . The method as claimed in  claim 1  wherein the element is a plurality of elements. 
     
     
         6 . The method as claimed in  claim 1  wherein the element is an explosive charge. 
     
     
         7 . The method as claimed in  claim 1  wherein causing the element to move radially outwardly is by shifting a member having a changing outside dimension to a position where the element is moved radially outwardly. 
     
     
         8 . The method as claimed in  claim 6  wherein the member is a piston. 
     
     
         9 . The method as claimed in  claim 1  wherein the load applied is tension. 
     
     
         10 . The method as claimed in  claim 1  wherein the load applied is rotation. 
     
     
         11 . The method as claimed in  claim 1  wherein the causing is repeated upon repositioning of the element to another azimuthal position of the tool. 
     
     
         12 . The method as claimed in  claim 11  further including operating an indexer to select the another azimuthal position. 
     
     
         13 . The method as claimed in  claim 12  wherein the indexer includes a J-slot. 
     
     
         14 . The method as claimed in  claim 1  further including jarring the element into the casing. 
     
     
         15 . The method as claimed in  claim 1  further including jarring the element out of the casing. 
     
     
         16 . The method as claimed in  claim 1  wherein the deforming opens a fluid passage through the casing. 
     
     
         17 . The method as claimed in  claim 1  wherein the deforming is plastic deformation. 
     
     
         18 . The method as claimed in  claim 1  wherein the deforming is weakening the casing. 
     
     
         19 . The method as claimed in  claim 1  wherein the failing is tearing the casing. 
     
     
         20 . A system for pulling casing comprising:
 a casing modification tool having an element radially displaceable into a casing disposed radially outwardly thereof, the element configured to deform the casing;   a casing spear operably connected to the casing modification tool, the spear configured to apply a load to the casing to fail the casing at the deformation.   
     
     
         21 . A borehole system comprising:
 a borehole in a subsurface formation;   a casing disposed in the borehole; and   a casing modification and pulling tool as claimed in  claim 1  disposed in the casing.