System and method for raially expanding a tubular element

Abstract

The invention discloses a system (FIG. 1 ) and a method for lining a wellbore. The system comprises a drill string ( 20 ) for drilling the wellbore; an expandable tubular element ( 84 ) enclosing the drill string ( 20 ), wherein a lower end portion of a wall of the expandable tubular element ( 14 ) is bent radially outward and in axially reverse direction to define an expanded tubular section ( 10 ) extending around an unexpanded tubular section ( 8 ); a pushing device ( 42 ) for pushing the unexpanded tubular section ( 8 ) into the expanded tubular section ( 10 ); and a releasable drilling annulus sealing device ( 70 ) for closing an annular opening between an upper end of the expandable tubular element and the drill string.

1 . A system for lining a wellbore, the system comprising:
 a drill string for drilling the wellbore;   an expandable tubular element enclosing the drill string, wherein a lower end portion of a wall of the expandable tubular element is bent radially outward and in axially reverse direction to define an expanded tubular section extending around an unexpanded tubular section;   a pushing device for pushing the expanded tubular section into the expanded tubular section;   a releasable drilling annulus sealing device for closing an annular opening between an upper end of the expandable tubular element and the drill string.   
     
     
         2 . The system of  claim 1 , wherein the expandable tubular element comprises a plurality of interconnected tubular sections. 
     
     
         3 . The system of  claim 2 , wherein respective ends of the interconnected tubular sections are connected to each other by a weld. 
     
     
         4 . The system of  claim 1 , wherein the drill string comprises a plurality of interconnected pipe sections, and wherein an upper end of the drill string is connected to an upper end connection part. 
     
     
         5 . The system of  claim 4 , wherein the drilling annulus sealing device is fixated with respect to the upper end connection part. 
     
     
         6 . The system of  claim 4 , wherein the drilling annulus sealing device is moveable with respect to the upper end connection part. 
     
     
         7 . The system of  claim 1 , wherein the drilling annulus sealing device encloses an upper end of the unexpanded tubular section. 
     
     
         8 . The system of  claim 1 , wherein the drilling annulus sealing device comprises a stinger which projects into the unexpanded tubular section. 
     
     
         9 . The system of  claim 1 , wherein the drilling annulus sealing device comprises at least one of a gripper for gripping the tubular element, one or more seals for sealing the annular opening, and a control line for activating the gripper and/or the one or more seals. 
     
     
         10 . The system of  claim 1 , comprising a gas tool which is arranged around the drill string for providing backing gas for welding an additional tubular section to the upper end of the unexpanded tubular section. 
     
     
         11 . The system of  claim 10 , wherein the gas tool is integrated in the stinger of the drilling annulus sealing device. 
     
     
         12 . The system of  claim 1 , comprising an emergency shut-off device which is movably arranged around the unexpanded tubular section for closing a gap between the additional tubular section and the unexpanded tubular section. 
     
     
         13 . The system of  claim 1 , comprising a blow-out preventer for closing off the wellbore in case of an emergency, wherein the blow-out preventer encloses the unexpanded tubular section and comprises:
 a cutter for cutting the unexpanded tubular section; and   at least one closure device for closing the wellbore.   
     
     
         14 . The system of  claim 13 , wherein the blow-out preventer is arranged on top of a blind annulus sealing device. 
     
     
         15 . Method for lining a wellbore using the system of  claim 1 .