A wellbore system, tool and method

Abstract

A well tool having a body configured for deployment in a tubular in a wellbore and having connection means ( 2; 2 a ) configured for connection to running 12 tools and control means ( 3 ) for connection to uphole control means, characterized 13 by a magnetic field generator ( 5 ) configured and controllable by the control means to generate a time—varying magnetic field. Use of the tool as a wellbore heating tool, a cement verification tool or a wellbore plugging tool.

What is claimed is: 
     
         1 . A well tool comprising:
 a body configured for deployment in a tubular in a wellbore and comprising a connection means configured for connection to running tools;   down, controller configured to connect to an uphole controller; and   a magnetic field generator configured and controllable by at least one of the downhole controller or the uphole controller to generate a time-varying magnetic field.   
     
     
         2 . (canceled) 
     
     
         3 . The well tool of  claim 1 , wherein the magnetic field generator comprises a rotatable member connected to a controllable drive means and comprising a plurality of permanent magnets assembled on at least a portion of the rotatable member, the permanent magnets having alternating polarity. 
     
     
         4 . (canceled) 
     
     
         5 . The well tool of  claim 3 , wherein the rotatable member comprises a cylindrical, frusto-conical or spherical shape and the plurality of permanent magnets comprises a plurality of first and second permanent magnets that are assembled at regular intervals on at least a portion of the rotatable member outer surface. 
     
     
         6 . The well tool of  claim 3 , wherein the rotatable member comprises a drum shape and the plurality of permanent magnets comprises a plurality of first and second permanent magnets that are assembled at regular intervals on an end surface of said drum and concentric with a drum axis of rotation. 
     
     
         7 . The well tool of  claim 3 , wherein the drive means comprises at least one of an electric motor and controllable power source or a turbine configured for connection to a fluid conduit and controllably operated by means of an injected fluid. 
     
     
         8 . (canceled) 
     
     
         9 . The well tool  claim 1 , wherein the tool comprises a housing enclosing at least the magnetic field generator; said housing comprising a material which is not significantly electrically conducting. 
     
     
         10 . The well tool  claim 1 , wherein the tool comprises a housing enclosing at least the magnetic field generator; said housing comprising an electrically conducting material, wherein the housing is heated when the magnetic field generator is operated. 
     
     
         11 . The well tool  claim 1 , further comprising an element comprising an electrically conducting and eutectic material arranged on the tool such that the element is influenced by the time-varying magnetic field generated by the magnetic field generator. 
     
     
         12 . (canceled) 
     
     
         13 . The well tool of  claim 11 , wherein the element comprises a sleeve encircling at least a portion of the tool body. 
     
     
         14 . (canceled) 
     
     
         15 . The well tool of  claim 1 , further comprising a sensor means for sensing at least one of rotational moments or electrical currents in the magnetic field generator. 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . A wellbore tubular comprising at least one element having an electrically conducting and eutectic material that is arranged on at least a portion of the tubular. 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . The wellbore tubular of  claim 19 , wherein the element is a sleeve which has been pre-installed on the tubular prior to the tubular being introduced into the wellbore. 
     
     
         24 . A wellbore system comprising
 a well tool comprising:
 a body configured for deployment in a tubular in a wellbore and comprising a connection means configured for connection to running tools, 
 a downhole controller configured to connect to an uphole controller, and 
 a magnetic field generator configured and controllable by at least one of the downhole controller or the uphole controller to generate a time-varying magnetic field: and 
   a wellbore tubular comprising least one element having an electrically conducting and eutectic material that is arranged on at least a portion of the tubular.   
     
     
         25 . The wellbore system of  claim 24 , wherein said at least one tool is arranged proximal to at least one element, wherein at least a portion the element is influenced by a time-varying magnetic field generated by the magnetic field generator when the tool is operated. 
     
     
         26 . A method of sealing an annular region in a wellbore comprising at least one wellbore tubular, the method comprising:
 conveying a well tool to a location in the tubular proximal to at least one element;   operating the well tool to generate a time-varying magnetic field, at a sufficient magnitude and duration until the element material reaches its melting temperature;   allowing the molten material to flow to a desired location; and   allowing the material to cool to a solid state, sealing, material.   
     
     
         27 . A method of forming a plug in a tubular, the method comprising:
 conveying a well tool to a location in the tubular;   operating the well tool to generate a time-varying magnetic field, at a sufficient magnitude and duration until the element material reaches its melting temperature;   allowing the molten material to settle on a plug foundation; and   allowing the material to cool to a solid state, sealing, material in the entire tubular cross-section.   
     
     
         28 . The method of  claim 27 , further comprising flowing molten material through at least one opening in the tubular wall, thereby forming a bridge plug extending into the annulus formed between the tubular outer wall and an adjacent formation or other tubular. 
     
     
         29 . A method of heating well fluids in a tubular the method comprising:
 conveying the a well tool to a desired location in the tubular; and   operating the well tool to generate a time-varying magnetic field, at a sufficient magnitude and duration until the housing has reached a desired temperature.   
     
     
         30 . The method of  claim 29 , further comprising: conveying the well tool to a vicinity of obstructive matters; and operating the well tool until such matter is melted or substantially dissolved. 
     
     
         31 . (canceled) 
     
     
         32 . A method of verifying wellbore cement, the method comprising
 conveying a well tool ( 1   e ) to a downhole location proximal to said cement;   operating the well tool to generate a time-varying magnetic field;   sensing rotational moments of a rotating cylinder or measure the electrical current in a coil array;   calculate the energy loss due to any conductive material in the cement.