Method of abandoning a well

Abstract

The invention provides a method of determining the condition of a cement bond of a casing in a wellbore. The method comprises perforating a tubing in the wellbore at a zone of interest and displacing a settable composition through the perforations into the annulus between the casing and tubing to secure the tubing. The method also comprises cutting the tubing and assessing the status of the cement bond of the casing.

1 . A method of determining the condition of a cement bond of a casing in a wellbore comprising;
 perforating a tubing in the wellbore at a zone of interest;   displacing a settable composition through the perforations into the annulus between the casing and tubing to secure the tubing;   cutting the tubing; and   assessing the status of the cement bond of the casing.   
     
     
         2 . (canceled) 
     
     
         3 . The method according to  claim 1  comprising securing the tubing rigidly by allowing the settable composition to set hard in the annulus between the casing and tubing prior to cutting the tubing. 
     
     
         4 . The method according to  claim 1  comprising providing a tubing cutter to cut a slot through the wall of the tubing. 
     
     
         5 . The method according to  claim 1  comprising deploying a milling tool to mill the tubing. 
     
     
         6 . The method according to  claim 5  comprising milling away the settable composition in the annulus between the casing and tubing. 
     
     
         7 . (canceled) 
     
     
         8 . The method according to  claim 5  comprising milling away the tubing up to the top of the settable composition in the annulus between the casing and tubing. 
     
     
         9 . The method according to  claim 1  comprising assessing the quality of the cement bond by deploying a cement bond logging tool through the tubing. 
     
     
         10 . The method according to  claim 1  comprising deploying a cement plug if the cement bond is shown to be of adequate and/or good quality. 
     
     
         11 . The method according to  claim 1  comprising pulling the tubing out of the casing if the cement bond is shown to be of poor quality. 
     
     
         12 . The method according to  claim 1  comprising assessing the quality of the cement bond at multiple positions and/or zones in the wellbore if the cement bond is shown to be of poor quality. 
     
     
         13 . The method according to  claim 1  comprising assessing the quality of the cement of a second and/or further zone by cutting the tubing at a second and/or further zone. 
     
     
         14 . The method according to  claim 13  comprising dropping the cut tubing further downhole to expose the cement bond at the second zone and/or further zone. 
     
     
         15 . The method according to  claim 14  comprising repositioning the cutting tool in the well in the event a good quality cement bond is not identified in the second and/or further zone. 
     
     
         16 . The method according to  claim 14  comprising making further cuts to the tubing and exposing the cement bond until a zone with good quality cement is identified. 
     
     
         17 . The method according to  claim 1  wherein the settable composition is selected from the group comprising cement, resin and/or gel. 
     
     
         18 . The method according to  claim 17  wherein the settable composition is cement and comprising deploying a cementing tool to displace a pre-determined amount of cement through the perforations into the annulus between the casing and the tubing. 
     
     
         19 - 29 . (canceled) 
     
     
         30 . A method of milling a tubing section in a wellbore casing comprising perforating the tubing section;
 passing a settable composition through the perforations into the annulus between the casing and tubing to secure the tubing; and   milling the tubing section and the cement securing the tubing section.   
     
     
         31 . The method according to  claim 30  comprising milling in an upward or downward direction in the wellbore. 
     
     
         32 . A method of determining the condition of a cement bond of a casing in a wellbore comprising;
 cutting the production tubing at a zone of interest;   dropping at least a section of the production tubing downhole; and   assessing the status of the cement bond of the casing.   
     
     
         33 . The method according to  claim 32  comprising cutting and/or milling the production tubing at a position in the wellbore lower than the zone of interest prior to cutting the production tubing at the zone of interest. 
     
     
         34 - 36 . (canceled)