Abstract: A drill bit suitable to be connected to a drill string for drilling a borehole into an earth formation, the drill string having a central longitudinal axis, the drill bit comprising a bit body connectable to the lower end of the drill string, and a cutting member provided with cutting devices at the outer surface thereof, the cutting member being rotatable relative to the bit body about a longitudinal axis of rotation extending eccentrically relative to the central longitudinal axis of the drill string, between a first rotational position[ and a second rotational position, whereby in said second rotational position the cutting devices arranged at a larger radial distance from the central longitudinal axis of the drill string than in said first rotational position.

Abstract: A method of isolating a section of downhole tubing comprises: running a length of expandable tubing (20) into a tubing-lined borehole (12, 14) and positioning the expandable tubing (20) across a section of tubing to be isolated; deforming at least portions of the expandable tubing (36, 40) to increase the diameter of the portions to sealingly engage the tubing (14) and to isolate the tubing section.

Abstract: A method and apparatus is provided for drilling and lining a wellbore in one downhole trip. The method comprises mounting a drill bit on a drill string including a section of expandable tubing and providing a tubing expander in the string, then rotating the drill bit and advancing the drill string through a bore, then passing the expander through the expandable tubing to expand the tubing, wherein the expandable tubing is deformed by compressive plastic deformation of the tubing with a localised reduction in wall thickness, resulting in a subsequent increase in tubing diameter, and then retrieving the drill bit from the bore through the expanded tubing.

Abstract: A tubing expansion device (20) is adapted to be advanced axially, without rotation, through tubing (10) to be expanded. The device (20) comprises a body (22) and a plurality of expansion members (30,32,34) mounted on the body (22), the expansion members (30,32,34) being independently radially movable. The expansion members may be rotatable, or may be non-rotating.

Abstract: Malware definition data for mobile computing devices 2 is generated from master malware definition data 44 by selecting those classes of malware threat to which the mobile computing device is vulnerable and then selecting the matching malware items from within the master malware definition data. A PC 6 to which the mobile computing device may be connected is responsible for downloading an updated version of the master malware definition data for its own use and generates appropriate mobile computing device malware definition data for transfer to the mobile computing device when it is connected to the PC. The scanner programs of both the PC and the mobile computing device may be similarly updated.

Abstract: When a user commands execution of a computer program to commence, a loader program 2 is first started. This loader program2 reads an encrypted version of the computer program 6 and decrypts it using a public key. This generates an executable version of the computer program 9 which is written directly to the computer memory 8. When the loader program 2 has decrypted the whole of the computer program 9 it starts execution of the computer program 9 it has written into the computer memory 8 and terminates itself or is terminated by the computer program it started. The computer program 9 written into the computer memory 8 will be written into its own memory space and will have its own execution thread. The encryption used may be public key/private key encryption.

Abstract: Monovalent and/or divalent cation-exchanged zeolite adsorbents, such as zinc-substituted zeolites, for use in separating nitrogen from a gas, such as air, and a process for use of the adsorbents in a PSA cycle to economically and effectively produce nitrogen from air.

Abstract: A process for making microporous membranes that incorporate selected gas selective species as surface sites in a controlled spacing and orientation manner and such membranes so formed being suitable for separating and purifying the selected gas from selected gas containing gas mixtures. An example is the use of oxygen selective transition element complexes (TECs) as surface sites for separating and purifying oxygen from oxygen-containing gas mixtures.

Abstract: A method and apparatus is provided for drilling and lining a wellbore in one downhole trip. The method comprises mounting a drill bit on a drill string including a section of expandable tubing and providing a tubing expander in the string, then rotating the drill bit and advancing the drill string through a bore, then passing the expander through the expandable tubing to expand the tubing, wherein the expandable tubing is deformed by compressive plastic deformation of the tubing with a localised reduction in wall thickness, resulting in a subsequent increase in tubing diameter, and then retrieving the drill bit from the bore through the expanded tubing.

Abstract: A method of expanding tubing comprises the steps: providing a length of expandable tubing; locating an expansion tool, such as a cone, in the tubing; and applying impulses to the tool to drive the tool through the tubing and expand the tubing to a larger diameter. The tubing may be located downhole and may have a solid wall or a slotted wall.

Abstract: A method and apparatus for creating a seal between two coaxial strings of pipe. The method and apparatus have utility in one embodiment for sealing the annulus between the tubing and the casing within a hydrocarbon wellbore. According to the method of the present invention, an expander tool is positioned at a selected depth within the tubing, and then actuated in order to expand the tubing against the inner wall of the casing wall. The expander tool is rotated in order to provide a fluid seal in the annulus. In this way, the tubing string becomes its own packer. In the preferred embodiment, an elastomeric seal is provided around the outer surface of the tubing to enhance the fluid seal. Further, a slip ring is provided around the outer surface of the tubing to provide a gripping means between the tubing and the casing. In the preferred embodiment, rollers of the expander tool are aligned with the seal ring and slip ring before expansion.

Abstract: A method of isolating a section of downhole tubing comprises: running a length of expandable tubing (20) into a tubing-lined borehole (12, 14) and positioning the expandable tubing (20) across a section of tubing to be isolated; deforming at least portions of the expandable tubing (36, 40) to increase the diameter of the portions to sealingly engage the tubing (14) and to isolate the tubing section.

Abstract: A ballnut assembly is provided in which a locknut (20), which is normally unloaded becomes loaded in the event of failure of a primary load path. This loading causes relative motion between Tocking nut (24) and the threads of a shaft (8) such that on clearance there between is eliminated. This causes frictional forces to initiate a lock-up of the locknut.

Abstract: A method of expanding tubing comprises locating an expansion tool in a section of tubing to be expanded, applying a fluid pressure to the tubing to create a fluid pressure expansion force and induce a hoop stress in the tubing, and applying a mechanical expansion force to the tubing via the expansion tool. The combined fluid pressure expansion force and mechanical expansion force is selected to be sufficient to induce expansion of the tubing.

Abstract: A technique for detecting Trojans and worms within packed computer files uses fingerprint data derived from the unpacked resource data associated with the packed computer files. The number of entries, the position within the resource data and size of the resource that is the largest resource specified, a timestamp value of compilation and a checksum value derived from the whole of the resource data may be included within a fingerprint value as characteristic of a particular set of resource data. A library of such fingerprint values may be generated for known Trojans and worms, or other programs it is wished to detect, and then a suspect file compared against this library of fingerprints.

Abstract: Methods and apparatus for shaping pipes, tubes, liners, or casing at downhole locations in wells. Use is made of rollers bearing radially outwards against the inside wall of the pipe (etc.), the rollers being rolled around the pipe to cause outward plastic deformation which expands and shapes the pipe to a desired profile. Where one pipe is inside another, the two pipes can be joined without separate components (except optional seals). Landing nipples and liner hangers can be formed in situ. valves can be deployed to a selected downhole location and there sealed to the casing or liner without separate packers. Casing can be deployed downhole in reduced-diameter lengths and then expanded to case a well without requiring larger diameter bores and casing further uphole. The invention enables simplified downhole working, and enables a well to be drilled & produced with the minimum downhole bore throughout its depth, obviating the need for large bores.

Abstract: A method of providing a downhole seal, such as a packer, in a drilled bore between inner tubing and outer tubing comprises: providing an intermediate tubing section defining a seal arrangement for engaging with the inner tubing; and radially plastically deforming the intermediate tubing section downhole to form an annular extension. The extension creates a sealing contact with the outer tubing.

Abstract: A method of expanding tubing downhole comprises providing a section of expandable tubing of a first diameter, and axially compressing the tubing to induce buckling, such that the buckled portion describes a larger second diameter. The resulting diametric expansion may be utilised to anchor or seal the tubing within a larger bore.

Abstract: A method of forming a seal between two tubular members (30,32) comprises providing a first tubular member (30) having an internal surface and an external surface describing a first diameter, with a recess (34) in the external surface at a seal portion of the first tubular member. A deformable circumferentially extending sealing member (36) is located in the recess, the sealing member describing an external diameter no greater than the first diameter. The first tubular member (30) is located within a second tubular member (32) and the seal portion of the first tubular member (30) is expanded such that the sealing member (36) engages an inner surface of the second tubular member (32).

Abstract: A method of forming expandable downhole tubing (10) comprises the steps of: providing a tubing section (12) of a first diameter; forming apertures in the tubing section (12); and then reducing the diameter of the apertured tubing section.