Abstract: A wellbore tubular flotation device comprises a housing having a locking element disposed thereon. The housing is shaped to move through an interior of a wellbore tubular segment. The locking element is shaped to engage the interior of the wellbore tubular segment. The locking element comprises a locking mechanism configured to urge the locking element into contact with the interior of the wellbore tubular. A burst disk is engaged with the housing and is shaped to close the tubular segment to fluid flow. A release mechanism is configured to reverse the urging of the locking mechanism when a release tool is moved through the housing.

Abstract: A method for recovering a conduit from a wellbore includes positioning an expander tool having at least one biasing element within the conduit an expander tool and exerting a force against the at least one biasing element to radially expand the conduit to an amount sufficient to fracture solids outside of and in contact with the conduit.

Abstract: A flotation device for a wellbore tubular has a flotation disk having a tapered exterior profile. A maximum external diameter of the flotation disk is such to enable free longitudinal movement within the wellbore tubular. A plurality of locking segments each has a tapered interior profile cooperatively engageable with the tapered exterior profile. Each locking segment has gripping elements on an exterior surface thereof to engage an inner wall of the wellbore tubular. The tapered exterior profile and the tapered interior profile cooperate to expand a diameter of the locking segments as profile engagement increases.

Abstract: A completion system comprises tubular components coupled together to form a completion string. In-flow control devices are provided to permit selective fluid communication between an internal bore of the completion string and the annulus. A reaming tool is provided at a leading end of the completion string and the reaming tool is run into the borehole with the completion string. The reaming tool comprises a fluid-powered drive unit, a reaming body and a reaming nose. In use, the completion string is located in the borehole and fluid is directed to the reaming tool to facilitate reaming of the borehole. A second tubular in the form of a washpipe may extend through an internal bore of the completion string for providing fluid to the reaming tool. The reaming tool is operable at a fluid pressure below a pressure which would activate the in-flow control devices.

Abstract: An apparatus for cutting a wellbore includes a motor having a stator and a rotor. The rotor has an output shaft connected to a cutting structure. The stator and rotor are spaced radially outwardly of the axis of rotation of the rotor such that at least one of the stator and the rotor had an access bore extending through the motor to adjacent the cutting structure. A further object can pass therethrough, without obstruction. The further object comprises a further cutting. A flow diverter is disposed in the motor proximate a connection between the motor and a wellbore tubular, and has a first fluid outlet in fluid communication with a power section of the motor, and a second fluid outlet in fluid communication with the access bore. The flow diverter is coupled to the stator such that axial loading created by fluid pressure is substantially transferred to the stator.

Abstract: A reaming tool for use in reaming a bore includes a body adapted for location in a bore. The body defines a rotor of a rotary drive arrangement. A shaft adapted for location is disposed in the body. The shaft defines a stator of the rotary drive arrangement. A seal element is disposed between the shaft and the body. The seal element defines a bearing surface for permitting sealed relative rotation of the rotary drive arrangement. The tool includes a reaming member, wherein relative rotation between the body and the shaft facilitates reaming of the bore by the reaming member.

Abstract: A reaming shoe for location in a bore has a rotationally balanced nose. A rotary drive is rotationally coupled to the reaming shoe to enable reaming of the bore. The assembly of the reaming shoe and the rotary drive is adapted to be coupled to a tubular component. The reaming shoe is mounted to the tubular component to enable rotation of the reaming shoe independently of the tubular component, such that the reaming shoe is rotatable at a different rotational speed than the tubular component.

Abstract: An apparatus for cutting a wellbore includes a motor with a stator and a rotor. The rotor includes an output shaft connected to a cutting structure to drive the cutting structure in use. The stator and rotor are spaced radially outwardly of the axis of the rotor such that at least one of the stator and the rotor has an access bore that extends through the motor to a position adjacent the cutting structure and through which a further object can pass without obstruction from the stator and rotor. The further object includes a further cutting structure. The motor workings are radially outward of the output shaft and the further cutting structure so as not to obstruct passage of the further cutting structure toward the cutting structure, such that the motor workings do not require drilling or removal to allow the further cutting structure access to the cutting structure.

Abstract: A method of running a tubular string into a wellbore comprises running a bore-lining tubular string into a wellbore substantially without rotation, while rotating a cutting structure at a distal leading end of the tubular string. Other methods provide for rotation of the string and the provision of a non-rotating stabiliser towards the leading end of the string.