Well abandonment

Abstract

A device for removing part of a liner or casing of a well or pile. The device includes a device body, which is arranged around a centreline of the device body and one or more hollow conduits comprising oxidizable material at least at a distal end. The one or more hollow conduits are arranged for having oxygen transported therethrough from a proximal end to the distal end. The device further including a supply of oxygen arranged to supply oxygen to proximal ends of the one or more hollow conduits and a feeding module connected to the device body and the one or more hollow conduits. The feeding module arranged for feeding the one or more hollow conduits with their distal end in a direction at least partially away from the centreline of the device body.

1 . A method for placing a seal plug in a liner of a well, the method comprising the steps of: 
 lowering a device for placing a seal plug into the liner of the well;   providing a flow of fluid to an inlet of a hollow chamber of a restriction member of the device for placing the seal plug, wherein the seal plug is at least partially positioned in the hollow chamber between the inlet and an outlet passage of the hollow chamber; and   allowing the seal plug to move relative to the restriction member by virtue of the hollow chamber becoming filled with fluid to release the seal plug into an unrestricted state wherein the seal plug forms a circumferential seal against an inner wall of the liner.   
     
     
         2 . The method of  claim 1 , wherein the device includes: 
 a seal plug arranged to form a circumferential seal against an inner wall of the liner in an unrestricted state, the seal plug comprising a radial clamping mechanism for clamping the seal plug in the liner, the radial clamping mechanism comprising at least one clamping member; and   a clamping mechanism restriction member for holding the radial clamping mechanism in a restricted state, wherein the radial clamping mechanism has a smaller outer footprint in the restricted state than in the unrestricted state and in the unrestricted state, the radial clamping mechanism is no longer restricted by the restriction member;   
       wherein the restriction member comprises a hollow chamber with an inlet for receiving a flow of fluid into the hollow chamber and an outlet passage arranged to allow passage of the radial clamping mechanism out of the hollow chamber, and the radial clamping mechanism is positioned at least partially in the hollow chamber between the inlet and the outlet passage.  
     
     
         3 . The method according to  claim 1 , further comprising releasing a temporary connection member connected between the restriction member and the at least one clamping member. 
     
     
         4 . The method according to  claim 1 , wherein the flow of fluid is provided to the hollow chamber through a sealant conduit, and wherein no air or gas is present in the sealant conduit and the hollow chamber while the device is lowered.  
     
     
         5 . The method according to  claim 1 , further comprising forming a cement plug on top of the seal plug. 
     
     
         6 . The method according to  claim 1 , further comprising positioning a tag plate on the cement plug, the tag plate comprising information indicative of the well. 
     
     
         7 . The method according to  claim 6 , wherein the tag plate comprises one or more legs or a skirt part protruding from the tag plate, which extends into the cement plug. 
     
     
         8 . The method according to  claim 6 , wherein the tag plate comprises legs which in an unrestricted state have an outer footprint, which is larger than an inner diameter of the liner in which the tag plate is placed, and wherein the legs are elastically deformed into a restricted state.  
     
     
         9 . The method according to  claim 1 , wherein the seal plug comprises a radial clamping mechanism which in an unrestricted state forms the seal with the inner wall of the liner to restrict fluid from flowing between the radial clamping mechanism and the inner wall of the liner. 
     
     
         10 . The method according to  claim 1 , further comprising venting air or other gas from the hollow chamber. 
     
     
         11 . The method according to  claim 10 , wherein the air or other gas is vented from the hollow chamber before the device is lowered more than a length of the device into the well. 
     
     
         12 . The method of  claim 1 , wherein the device includes: 
 a seal plug arranged to form a circumferential seal against an inner wall of the liner in an unrestricted state, the seal plug comprising a radial clamping mechanism for clamping the seal plug in the liner, the radial clamping mechanism comprising at least one clamping member; and   a clamping mechanism restriction member for holding the radial clamping mechanism in a restricted state, wherein the radial clamping mechanism has a smaller outer footprint in the restricted state than in the unrestricted state;   
       wherein the restriction member comprises a hollow chamber with an inlet for receiving a flow of fluid and an outlet passage arranged to allow passage of the radial clamping mechanism, and the radial clamping mechanism is positioned at least partially in the hollow chamber between the inlet and the outlet passage.