Abstract: A method of recovering casing from a wellbore in which: a logging tool is run to an estimated stuck point of the casing through the central bore of the casing spear and casing cutter; the casing spear is attached to the casing and tension applied so that logging can be performed over a length at an estimated stuck point both with and without tension to provide the verified stuck point; and the casing cutter is positioned relative to this to cut the free casing; and the spear used to remove it. The method can be performed on a single trip. Embodiments include incorporating a packer to circulate fluid during casing cutting; a disconnect, anchor mechanism and motor to allow use of a motor to operate the cutter; and a Down Hole Power Tool with a method of establishing the required force to recover a length of stuck casing.

Abstract: A thru-tubing recover string (10) and method of moving a stuck object (14) in tubing in a well (16). A bottom hole assembly (22) is connected to a work string and includes a first (32) and a second tool (34), each tool configured to apply a force to the object in order to move the object (14), the first force being an impulse force, the second force being a static force, and the tools being operable independently so that an operator can apply either force in the event that application of one type of force on the object fails to move the object. Embodiments are described for the first tool (32) being a hammer tool or a jar and the second tool being a pulling tool such as a jack. The invention finds application in removing stuck objects such as plugs or actuating elements on tools such as sliding sleeves in production tubing.

Abstract: A single trip casing cutting and pulling assembly which includes a casing spear (12), a mud motor (16) and a casing cutter (18), wherein a valve (14) is located between the casing spear (12) and the mud motor (16). The casing spear is operated by fluid flow from surface and the valve (14) prevents operation of the casing cutter (18) until the casing spear (12) is set and casing cutting is required. A method is described for cutting and pulling casing which does not require any rotation of the drill string to operate any part of the casing cutting and pulling assembly. An embodiment is described which includes retrieving the seal assembly (48) on the same trip. Further embodiments describe performing an integrity test and a circulation test on the same trip with the option of making further cuts at shallower depths on the same trip until a section of cut casing can be recovered.

Abstract: A method and apparatus to move an object in an open hole section of a wellbore. A bottom hole assembly including a downhole pulling tool and fishing device is described. The downhole pulling tool includes an open hole anchor to allow location of the downhole pulling tool in the open hole section of the wellbore so as to reduce the operating distance between the downhole pulling tool and the fishing device. An embodiment in which a cut section of tubular is removed from the open hole section is described. A casing cutter may also be located in the bottom hole assembly to cut the tubular on the same trip in the well as removing the cut section of tubular.

Abstract: A method of recovering casing from a wellbore in which: a logging tool is run to an estimated stuck point of the casing through the central bore of the casing spear and casing cutter; the casing spear is attached to the casing and tension applied so that logging can be performed over a length at an estimated stuck point both with and without tension to provide the verified stuck point; and the casing cutter is positioned relative to this to cut the free casing; and the spear used to remove it. The method can be performed on a single trip. Embodiments include incorporating a packer to circulate fluid during casing cutting; a disconnect, anchor mechanism and motor to allow use of a motor to operate the cutter; and a Down Hole Power Tool with a method of establishing the required force to recover a length of stuck casing.

Abstract: A method for well abandonment in a cased well bore by perforating, washing and cementing to provide a plug over a longitudinal section of the well, wherein logging of the washed outer annulus is performed to evaluate the effectiveness of the wash and determine the most appropriate plugging technique. One of perf, wash and cement; cut and pull; and section milling are described dependent upon the material left in the outer annulus following the washing step. Verification of the washing step in a perf wash and cement well abandonment procedure is obtained.

Abstract: A thru-tubing recover string (10) and method of moving a stuck object (14) in tubing in a well (16). A bottom hole assembly (22) is connected to a work string and includes a first (32) and a second tool (34), each tool configured to apply a force to the object in order to move the object (14), the first force being an impulse force, the second force being a static force, and the tools being operable independently so that an operator can apply either force in the event that application of one type of force on the object fails to move the object. Embodiments are described for the first tool (32) being a hammer tool or a jar and the second tool being a pulling tool such as a jack. The invention finds application in removing stuck objects such as plugs or actuating elements on tools such as sliding sleeves in production tubing.

Abstract: A circulation test tool and method of performing a circulation test in a wellbore during single-trip casing cutting and removal. An anchor mechanism (20), a mechanical-set retrievable packer (22) and a cutting mechanism (18) allow gripping and cutting of casing (14) with the mechanical set-retrievable packer (22) being set after the cut to carry out the circulation test. The well is kept under control during the cut by application of tension on the drill string to set the packer (22) at any time. The arrangement provides full annulus flow pass at the packer during cutting. Embodiments describe additional features of a drill to dress a cement plug or a settable bridge plug.

Abstract: A downhole anchor mechanism (110) which can be set on at least two successive standard diameters of casing (232). The tool body has a recess into which a split cone (70) is located. The increased thickness of the split cone (70) provides for a greater thickness of slip (90), giving increased radial travel of the slips 90 when moved axially over the split cone (70). The cone (70) and slips (90) are profiled to provide two ramps/slopes for increased structural integrity and a greater ramp angle to reduce the axial travel of the slips to achieve the increased radial travel. The downhole anchor mechanism (110) provides anchoring of a work string on two standard diameters of casing in a single trip in a wellbore.

Abstract: Milling systems, tools, and methods include using a mill with secondary attrition system to re-mill cuttings and other debris away from the face of the mill. The secondary attrition system may be located uphole of the mill may be used to stage conditioning and re-sizing of debris. After debris is generated by the mill, the secondary attrition system may re-mill the debris to a finer size before allowing the debris to pass out of the sleeve. The debris may be re-milled by secondary cutting elements while within an annular gap positioned radially between the sleeve and a drive shaft for the mill. The annular gap may have a variable width as a result of a tapered outer surface of the drive shaft and/or a tapered inner surface of the sleeve. The variable width may cause debris to be re-milled into increasingly finer sizes.

Abstract: A well bore integrity test tool (10) and method of pressure integrity testing a well bore by performing positive and negative pressure tests in a well bore in multiple locations in the well and on the same trip as other operations in the well bore. The tool includes a resettable anchor mechanism (20) and a tension set packer assembly (22). An embodiment of performing a dress-off, integrity testing, casing cutting and pulling in a single trip for well abandonment is described.

Abstract: A method and apparatus for single-trip casing cutting and pulling for well abandonment and slot recovery. Perforations (28) are made in the casing (12) at a maximum depth using a punch tool (18) and a pulsed fluid circulated through the perforations (28) to determine a return at surface. In the event of a return at surface being detected, the casing (12) is cut and then pulled with assisted vibratory action. When no return is detected, perforations (28) are made at increasingly shallower depths until a return is detected and the casing (12) is then cut and pulled. This ensures the maximum length of casing (12) is cut and pulled on a single trip in the well bore.

Abstract: A single trip casing cutting and pulling assembly which includes a casing spear (12), a mud motor (16) and a casing cutter (18), wherein a valve (14) is located between the casing spear (12) and the mud motor (16). The casing spear is operated by fluid flow from surface and the valve (14) prevents operation of the casing cutter (18) until the casing spear (12) is set and casing cutting is required. A method is described for cutting and pulling casing which does not require any rotation of the drill string to operate any part of the casing cutting and pulling assembly. An embodiment is described which includes retrieving the seal assembly (48) on the same trip. Further embodiments describe performing an integrity test and a circulation test on the same trip with the option of making further cuts at shallower depths on the same trip until a section of cut casing can be recovered.

Abstract: A resettable mechanism for preventing the accidental actuation of a load set downhole tool and method of use. The resettable mechanism provides a collet (52) and a detent (56) with a collet ring arranged to ride over the detent under a load in excess of the operating load of the downhole tool and the collet load. Reversing the loading resets the mechanism and the downhole tool. A disengagement assembly (66) is described to disenable the detent (56) and operate the downhole tool at the operating load. Embodiments to a retrievable mechanical tension-set packer and a casing cutting and removal system are described which prevent premature actuation of the packer when run from floating structures.

Abstract: A method and apparatus for single-trip casing cutting and pulling for well abandonment and slot recovery. Perforations (28) are made in the casing (12) at a maximum depth using a punch tool (18) and fluid circulated through the perforations to determine a return at surface. In the event of a return at surface being detected, the casing (12) is cut and pulled. When no return is detected, perforations are made at increasingly shallower depths until a return is detected and the casing (12) is then cut and pulled. This ensures the maximum length of casing (12) is cut and pulled on a single trip in the well bore (10).

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.

Abstract: A method for removing one or more control lines (15) in a well (1), the control lines (15) running in an annulus behind a tubular (7) in the wellbore, during a well abandonment procedure comprising the steps: perforating the tubular (7) at a location adjacent the one or more control lines (15); displacing a self-supporting settable composition (21) through the perforations (20) into the annulus (18) to secure the one or more control lines (15) in place; cutting the tubular (7) and the one or more control lines (15) at the location of the self-supporting settable composition (21); washing away the self-supporting settable composition (21); and removing at least a portion of the one or more control lines from the wellbore. Embodiments are described for control lines (15) run in an annulus (18) between production tubing (7) and casing, pulling the production tubing (7) with the control lines (15), and milling the production tubing and control lines in a rigless method for well abandonment.

Abstract: A rigless method for abandoning a well in which the production tubing (7) and control lines (15) are left in place. The production tubing (7) is perforated at a zone of interest at any position in the well. A settable composition (21) which is dissolvable in acid is injected through the perforations (20a, 20b) into the annulus between the casing (5) and the production tubing (7) over the zone of interest and allowed to set. The composition supports the tubing (7) and secures the control lines (15) so that they can be cut and milled away to expose the casing. An acid wash is performed to remove all the settable composition and clean the casing (5) in preparation for a cement bond log to be performed. If the quality of the cement bond is acceptable a cement plug (28) is deployed. Further cuts in the production tubing (7) can be made to expose further sections of casing (5) in the event that the cement bond log is unacceptable.

Abstract: A method and apparatus for single-trip casing cutting and pulling for well abandonment and slot recovery. Perforations (28) are made in the casing (12) at a maximum depth using a punch tool (18) and a pulsed fluid circulated through the perforations (28) to determine a return at surface. In the event of a return at surface being detected, the casing (12) is cut and then pulled with assisted vibratory action. When no return is detected, perforations (28) are made at increasingly shallower depths until a return is detected and the casing (12) is then cut and pulled. This ensures the maximum length of casing (12) is cut and pulled on a single trip in the well bore.

Abstract: A method and apparatus for the combined cleaning and plugging of an annulus in a well across a longitudinal section of the well were the annulus is located outside a conduit in the well. The conduit is perforated over the longitudinal section. Washing fluid is passed through the longitudinal section to clear material in the annulus before the longitudinal section is plugged. Pressure variations are created in the washing fluid by use of a flow modifier device to pulse the washing fluid. Embodiments include creating pressure variations in the plugging material.