Apparatus and method for abandoning a well

Abstract

Apparatus for recovery of sections of tubing and inter alia, the tubing hanger, from a subsea well to enable the abandonment of a subsea well to be accomplished from a mono-hull vessel includes a dual gripper assembly ( 1 ) adapted for onshore or offshore deployment is configured to handle oilfield tubulars and associated completion equipment and configured for attachment to a wellhead structure and subsequent reciprocation cycles whereby oilfield tubulars can be run-in hole or pulled to surface without requiring a riser. A cutter mechanism ( 22 ) is disclosed for severing sections of tubular to form a clean cut end for attachment of a connection mandrel. The individually controllable gripping devices ( 19, 20 ) are operated such that during a reciprocation cycle at least one of the gripping devices is engaged around the tubular body for supporting same, and the other is spaced from the tubular body sufficiently for said other gripping device to slide over the tubular body to be selectively re-positioned to take up a fresh gripping position on the same or a further tubular body. The respective gripping devices can be used to bring together tubulars to be connected using a connection mandrel ( 28 ) or to manipulate a running and recovery tool ( 26 ), and to make up or break standard tool joints of wellbore tubulars. A method for pulling or running a completion is disclosed.

1 . Apparatus for recovery of sections of wellbore tubular from a subsea well to enable the abandonment of a subsea well to be effected from a mono-hull vessel, wherein the apparatus includes a dual reciprocating gripper assembly ( 1 ) comprising first and second gripper means ( 19 ,  20 ) with corresponding actuating means comprising cylinders ( 18 ) for use in the subsea installation or removal of a wellbore tubular from a wellbore, and a cutting device ( 22 ) for the purpose of disconnecting lengths of said wellbore tubular. 
     
     
         2 . Apparatus as claimed in  claim 1 , wherein the gripper means has slotted sections ( 47 ) to enable the through passage of gauge cable ( 43 ) or control lines ( 44 ), without damage to said cable and lines. 
     
     
         3 . Apparatus as claimed in  claim 1 , wherein the gripper control system automatically senses during a reciprocation cycle the proximity of a tubular connector or cable clamping device and opens and closes the gripper means at the appropriate point in the reciprocation cycle. 
     
     
         4 . Apparatus as claimed in  claim 1 , where said gripper means are adapted to rotate about an axis to apply torque to a tubular, to enable use for making and breaking of wellbore tubulars at a subsea wellhead. 
     
     
         5 . Apparatus as claimed in  claim 1 , wherein the actuating means comprises main cylinders ( 18 ) for reciprocating the gripper means, and high capacity auxiliary cylinders ( 41 ) to provide additional lifting force. 
     
     
         6 . Apparatus as claimed in  claim 1 , configured for operational use with guide lines ( 23 ) whereby said assembly can be deployed and recovered on said guide lines and connected or disconnected remotely underwater. 
     
     
         7 . Apparatus as claimed in  claim 1 , wherein said cutting device is remotely operable by use of a remotely operated underwater vehicle. 
     
     
         8 . Apparatus as claimed in  claim 1 , wherein a mechanism for making connections underwater, e.g. comprising tubing tongs, is provided to facilitate subsea connection of tubulars. 
     
     
         9 . Apparatus as claimed in  claim 1 , wherein said first and second gripper means are configured as upper and lower gripper means, whereby the lower gripper means is operable to suspend the wellbore tubular, while the upper gripper means is operable to locate, secure, axially guide and connect a connection mandrel ( 28 ) into said wellbore tubular. 
     
     
         10 . Apparatus as claimed in  claim 9 , wherein the connection mandrel is deployed underwater on coiled tubing from a vessel. 
     
     
         11 . Apparatus as claimed in  claim 9 , wherein the connection mandrel is deployed underwater on a rope or cable from a vessel. 
     
     
         12 . Apparatus as claimed in  claim 1 , wherein the assembly is adapted for suspending and centering a dual bore tubing with respect to a longitudinal central axis of said dual reciprocating gripper assembly. 
     
     
         13 . Apparatus as claimed in  claim 1 , operably associated with a device for rotating and orientating a dual bore tubing about the centerline of said dual reciprocating gripper assembly. 
     
     
         14 . Apparatus ( 1 ) for the installation or removal of a tubular body from a wellbore, said assembly being adapted for removable mounting upon a wellhead structure, and comprising first and second individually controllable gripping devices ( 19 ,  20 ) adapted to selectively engage around a tubular body, said assembly being operatively connected to control means to operate said gripping devices and configured such that during a reciprocation cycle step to install or remove a tubular body at least one of the gripping devices is engaged around the tubular body for supporting same, and the other is spaced from the tubular body sufficiently for said other gripping device to slide over the tubular body to be selectively re-positioned to take up a fresh gripping position on the same or a further tubular body, and a tubing hanger retrieval tool ( 26 ) for connection to the tubing hanger, and high capacity auxiliary cylinders ( 41 ) to provide additional lifting force to unseat the tubing hanger. 
     
     
         15 . Apparatus as claimed in  claim 14 , wherein the dual reciprocating gripping devices are configured to apply torque to the tubular body, optionally during a reciprocation step. 
     
     
         16 . Apparatus according to  claim 14 , wherein the gripping devices comprise plurality of cooperating segments ( 46 ) each having a slip face ( 50 ) comprising a plurality of ball bearings ( 51 ) pressed onto it. 
     
     
         17 . Apparatus as claimed in  claim 16 , wherein at least one slot ( 47 ) is provided between the segments to permit spacing for cables ( 43 ) or lines ( 44 ) to pass through the gripper assembly. 
     
     
         18 . Apparatus as claimed in  claim 14 , wherein the gripping devices comprise cooperating slip face ( 50 ) and slip trunnion ( 52 ) parts, wherein the cooperating surfaces comprise a plurality of ramps whereby relative longitudinal translation of the ramps results in lateral movement of the slip surface with respect to the slip trunnion. 
     
     
         19 . A method of pulling a completion tubular from a subsea well comprising retrievably deploying a retrieval tool and a dual reciprocating gripper assembly from a surface vessel to the wellhead, operating the dual reciprocating gripper assembly to bring the retrieval tool into operative contact with a subsea tubing hanger at the wellhead, engaging the tubing hanger with the tool while gripping and rotating the tool, running a connection mandrel from the surface vessel to the wellhead, connecting the mandrel to the retrieval tool, operating the dual reciprocating gripper assembly to unlatch the tubing hanger, raising the retrieval tool and tubing hanger while supporting the tubular at the wellhead, separating the tubing hanger from the supported tubular, recovering the dual reciprocating gripper assembly and the tubing hanger with connection mandrel and retrieval tool to the surface vessel, re-running the connection mandrel and the dual reciprocating gripper assembly to the wellhead, operating the dual reciprocating gripper assembly to engage the connection mandrel with the supported tubular, and subsequently operating the dual reciprocating gripper assembly to successively engage and pull the tubular, wherein one of the grippers of the dual reciprocating gripper assembly supports the tubular while the other re-positions with respect to the tubular to take up the load. 
     
     
         20 . A method as claimed in  claim 19 , wherein the dual reciprocating gripper assembly comprises first and second gripper means ( 19 ,  20 ) with corresponding actuating means comprising cylinders ( 18 ), and a cutting device ( 22 ) for the purpose of disconnecting lengths of said wellbore tubular.