Specialised Petroleum Services Group Limited

Ardyne Holdings Limited

M-i Drilling Fluids UK Limited

Schlumberger Technology Corporation

Sps-afos Group Limited

Specialized Petroleum Services Group Limited

Weatherford/lamb, Inc.

M-l Drilling Fluids UK Limited

Nodeco Limited

Specialised Petroleum Group Services Limited

Services Petroliers Schlumberger

George Telfer

Michael Wardley

James Linklater

Paul David Howlett

James Edward Atkins

Alan Fairweather

Edward Docherty Scott

Stephen Lewis

John Chrysostom Wolf

Mark Carmichael

Mikhail V Gotlib

Jose Hurtado

David Stewart

Wojciech Buczak

Alan Fair-Weather

Rae Andrew Youngor

Alasdair Tait

Juan Pablo Macin Moreno

A technique facilitates temporary plugging of a well string via a ball seat assembly which may be actuated on demand. The ball seat assembly includes a ball seat mechanism which works in cooperation with an on-demand assembly actuated via a pattern of pressure changes applied within the ball seat assembly. The on-demand assembly is constructed such that the pattern of pressure changes enables shifting of the ball seat mechanism to a ball release position. However, the ball seat mechanism is not able to function until the desired pattern of pressure changes is completed. Additionally, the on-demand assembly may be structured such that the ball seat mechanism is transitioned to the ball release position at a low pressure point of the pattern of pressure changes to avoid pressure surges within the well string.

On demand low shock ball seat system and method

A technique facilitates reducing or eliminating the risk of premature actuation of a liner hanger system and/or premature release of a miming tool. According to an embodiment, the technique utilizes a running string for deploying a liner hanger assembly having a liner hanger which may be actuated at a desired location to suspend a liner/casing from a surrounding casing string. An anti-preset module may be used in cooperation with the liner hanger to prevent premature actuation of the liner hanger. By way of example, the anti-preset module may use pressure equalization between a region within the miming string and a region between the miming string and the liner hanger to prevent pressure imbalances which could actuate the liner hanger. Additionally, a locking mechanism, e.g. releasable lock dogs, may be used to temporarily lock the liner hanger against premature actuation.

Liner hanger system and method with non-pressure sensitive actuation

A resettable mechanism and a method of controlled actuation of a hydraulically operated downhole tool to allow selective operation of the downhole tool in a wellbore. The resettable mechanism provides an inner sleeve member which is longitudinally moveable between a first and second position which opens and closes a fluid pathway to at least one actuation port on the downhole tool. Movement of the inner sleeve member is controlled via an indexing mechanism operated by drop balls. An embodiment of a casing recovery system is described mechanism operated wherein a downhole pulling tool is selectively actuated so as to prevent operation of the pulling tool while a hydraulically operated casing cutter is cutting casing.

Relating to well abandonment and slot recovery

A downhole actuator () includes a piston () within a chamber () on which fluid can act on either side to hydraulically activate the actuator. A hydrostatic equilibrium device () and a valve () are mounted around the hydraulic actuator. With a radial port () of the hydrostatic equilibrium device closed and the valve closed to seal the string, pumping fluid through the string operates the actuator. Pressure overbalance prevents movement of the piston (). The radial port () is opened to drain fluid from the string until equilibrium is reached with the annular volume and the piston () can be moved.

Or relating to well abandonment and slot recovery

A single trip casing cutting and pulling assembly which includes a casing spear (), a mud motor () and a casing cutter (), wherein a valve () is located between the casing spear () and the mud motor (). The casing spear is operated by fluid flow from surface and the valve () prevents operation of the casing cutter () until the casing spear () 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 () 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.

Well abandonment and slot recovery

A downhole tool which allows the selective operation of a second fluid pressure activated tool below a first fluid pressure activated tool on a tool string in a well. The downhole tool has a piston sleeve moveable inside a cylindrical body between a first position in which a small flow area is provided through the tool and a second position in which a larger flow area is provided. The piston sleeve is held in the first position by a magnet and the first fluid pressure activated tool can be operated by increasing fluid pressure above the tool up to a cracking pressure level which matches the pulling strength of the magnet. Increasing fluid pressure to the cracking pressure therefore selectively moves the piston sleeve to the second position in which the second fluid pressure activated tool can be operated. The downhole tool is resettable.

Downhole tool

The invention provides a downhole tool for cutting a wellbore casing. The downhole tool comprises a gripping mechanism for gripping a section of wellbore casing and a cutting mechanism configured to cut the casing. The grip mechanism is configured to grip a range of casing diameters.

Downhole cut and pull tool and method of use

Method and apparatus for single-trip cementing and casing cutting for well abandonment and slot recovery. Using a tool string including a casing cutter and a stinger, where the casing cutter has a central through bore including a wall to isolate the cutting assembly from the cement, cement can be passed through the cutter and deposited using the stinger to form a plug. Embodiments of casing cutters are provided for parting an upper length of casing from a lower length of casing.

A circulation test tool and method of performing a circulation test in a wellbore during single-trip casing cutting and removal. An anchor mechanism (), a mechanical-set retrievable packer () and a cutting mechanism () allow gripping and cutting of casing () with the mechanical set-retrievable packer () 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 () 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.

Downhole test tool and method of use

Method and apparatus for single-trip cementing and casing cutting for well abandonment and slot recovery. A casing cutter is described which has a central through bore including a wall to isolate the cutting assembly from cement being passed through the casing cutter. The casing cutter is run in a cased well bore, cementing occurs through the casing cutter to form a cement plug and then the casing is cut. Embodiments of casing cutters are provided for parting an upper length of casing from a lower length of casing.

Method and tool for well abandonment and slot recovery

Method and apparatus for removing a section of well tubing. The well tubing () is milled in an upward direction on a hydraulic tensioning device () which maintains a constant load on the section mill so that long sections of tubing can be removed in a near continuous procedure on a single trip into the well. The hydraulic device includes an indicator () to provide a signal as the device nears each end of a stroke to inform a user that: the section mill is about to bottom out and the work string needs to be raised to extend the device; and the device is fully extended and can begin another stroke. Embodiments are described for use in a rigless well abandonment procedure.

Well abandonment

A downhole anchor mechanism () which can be set on at least two successive standard diameters of casing (). The tool body has a recess into which a split cone () is located. The increased thickness of the split cone () provides for a greater thickness of slip (), giving increased radial travel of the slipswhen moved axially over the split cone (). The cone () and slips () 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 () provides anchoring of a work string on two standard diameters of casing in a single trip in a wellbore.

Downhole anchor mechanism

A well bore integrity test tool () 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 () and a tension set packer assembly (). An embodiment of performing a dress-off, integrity testing, casing cutting and pulling in a single trip for well abandonment is described.

A resettable mechanism for preventing the accidental actuation of a load set downhole tool and method of use. The resettable mechanism provides a collet () and a detent () 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 () is described to disenable the detent () 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.

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.

Growing community of inventors

Aberdeen, United Kingdom

George Telfer