Abstract: The present invention provides a swivel sub for connection in a work string between a workstring and a downhole apparatus. The swivel sub includes a first substantially cylindrical body, including a sleeve portion having one or more teeth and a second substantially cylindrical body being partially located within the sleeve portion. The bodies are arranged to rotate relative to each other. The swivel sub also includes a sliding sleeve, having one or more teeth arranged mutually engage with the first teeth is axially moveable between disengaged and engaged positions, in one embodiment by a pressure differential being created in the sub. Further, the present invention provides methods for of running the tool, with particular application to setting and hanging of liners and screens.

Abstract: An apparatus and corresponding method in which the apparatus includes a dielectric waveguide and a metallic waveguide. The dielectric waveguide has an effective mode index and a longitudinal dimension. The metallic waveguide has a longitudinal dimension and supports a surface plasmonic mode of propagation for a wavelength lambda. The metallic waveguide and the dielectric waveguide are adjacent to each other and overlap each other by a length along the longitudinal dimensions of both the dielectric waveguide and the metallic waveguide, wherein the length is greater than the wavelength lambda in the metallic waveguide. The metallic waveguide is coupled to the dielectric waveguide where the metallic waveguide and the dielectric waveguide overlap each other.

Abstract: An apparatus, system, and method comprise a magnetoresistive head configured to respond to magnetization states of patterned cells formed on a patterned medium. The magnetoresistive head detects the magnetization states of at least two patterned cells formed on a patterned medium. The magnetoresistive head generates a readback signal based on the magnetization state of the at least two patterned cells. A detector circuit coupled to the head determines a bit pattern corresponding to the readback signal. A processor circuit coupled to the detector circuit determines positional information associated with the magnetoresistive head relative to the at least two patterned cells based on the bit pattern. The system further comprises a patterned medium.

Abstract: A tubing shoe (10) for use on work strings in well bores as are typically utilised in oil and gas production. The shoe comprises a cylindrical body (12) upon which is arranged a reaming portion (22) including pairs of teardrop shaped raised reaming members (26), each pair being mounted oppositely, in parallel and longitudinally along the body. Adjacent pairs of members provide a funnel (42) for collecting approaching debris and a channel for grinding the debris. A nose (14) may be mounted on the end of the shoe, the nose being eccentric or including cutting blades to assist the shoe in breaking through shale and clay stone bridges. A non-aggressive stabiliser (54) in the form of helically arranged blades may also be located on shoe.

Abstract: An apparatus, system, and method comprise a magnetoresistive head configured to respond to magnetization states of patterned cells formed on a patterned medium. The magnetoresistive head detects the magnetization states of at least two patterned cells formed on a patterned medium. The magnetoresistive head generates a readback signal based on the magnetization state of the at least two patterned cells. A detector circuit coupled to the head determines a bit pattern corresponding to the readback signal. A processor circuit coupled to the detector circuit determines positional information associated with the magnetoresistive head relative to the at least two patterned cells based on the bit pattern. The system further comprises a patterned medium.

Abstract: An apparatus for producing an optical spot on the order of 25 nm in a recording media. The apparatus includes an optical transducer comprising a waveguide which defines an aperture adjacent to an air bearing surface of the transducer adjacent a recording media. The transducer includes a protrusion extending beyond the plane of the air bearing surface extending toward the recording media.

Abstract: The present disclosure is directed to a micromachined rotary actuator constructed of a central portion and an outer portion at least partially surrounding the central portion and separated from the central portion by an in-plane gap. A plurality of arms are each connected at one end to the central portion and at another end to the outer portion so as to span the in-plane gap. The arms are constructed of a plurality of horizontally stacked materials positioned to enable the arms to bend in-plane when heated. Conductors are positioned within the actuator for heating the arms. Because of the rules governing abstracts, this abstract should not be used to construe the claims.

Abstract: A swivel sub for connection in a work string between a workstring and a downhole apparatus is disclosed. The sub has a first substantially cylindrical body, including a sleeve portion having one or more teeth and a second substantially cylindrical body being partially located within the sleeve portion. The bodies are arranged to rotate relative to each other. A sliding sleeve, having one or more teeth arranged mutually engage with the first teeth is axially moveable between disengaged and engaged positions, in one embodiment by a pressure differential being created in the sub. Methods of running the tool are described, with particular application to setting and hanging of liners and screens. The invention also offers advantages for drilling applications.

Abstract: A tubing shoe (10) for use on work strings in well bores as are typically utilised in oil and gas production. The shoe comprises a cylindrical body (12) upon which is arranged a reaming portion (22) including pairs of teardrop shaped raised reaming members (26), each pair being mounted oppositely, in parallel and longitudinally along the body. Adjacent pairs of members provide a funnel (42) for collecting approaching debris and a channel for grinding the debris. A nose (14) may be mounted on the end of the shoe, the nose being eccentric or including cutting blades to assist the shoe in breaking through shale and clay stone bridges. A non-aggressive stabiliser (54) in the form of helically arranged blades may also be located on shoe.

Abstract: An apparatus for producing an optical spot on the order of 25 nm in a recording media. The apparatus includes an optical transducer comprising a waveguide which defines an aperture adjacent to an air bearing surface of the transducer adjacent a recording media. The transducer includes a protrusion extending beyond the plane of the air bearing surface extending toward the recording media.

Abstract: A tool for reducing torque on work string, eg for gas or oil production, comprises an upper clamp (2), a lower clamp (3) and connection means (4), the three components formed as a unitary structure (1). The tool also comprises bearing means, preferably made from an elastomeric compound, and an annular body (7) (see FIG. 4) held in place over the connection means by the clamps. The clamps may comprise spigots (5) for retaining the connection means. In a preferred embodiment the annular body is in two semi-annular components connected at one end to allow them to pivot, and the other end comprises mating castellations for receiving a fastening pin. The annular body may comprise a number of replaceable wear pads (14) which may be made of bronze or an elastomer. The unitary structure of the tool enhances the integral strength and efficiency of the clamps.

Abstract: A device for writing data to a recording medium and a method for fabricating the device is presented. According to one embodiment, the device includes an electrical conductor having a cross-track portion, wherein the cross-track portion includes first and second opposing surfaces, and wherein the cross-track portion defines an aperture extending from the first surface to the second surface. The device also includes a dielectric portion disposed in the aperture such that the dielectric portion defines a ridge waveguide having a lowest-order mode cut-off frequency that is less than the frequency of incident optical energy used to heat the recording medium.

Abstract: A longitudinal recording head (50, 56, 60) for use with magnetic recording media includes a non-uniform gap (54, 59, 64) between first (51, 57, 61) and second magnetic (52, 58, 62) poles which focuses magnetic flux onto a small area of the magnetic recording medium. The non-uniform gap is preferably in the form of a cavity that is contoured to produce the desired flux pattern. Longitudinal recording heads incorporating the non-uniform gap are capable of improved recording densities.

Abstract: A device for writing data to a recording medium and a method for fabricating the device is presented. According to one embodiment, the device includes an electrical conductor having a cross-track portion, wherein the cross-track portion includes first and second opposing surfaces, and wherein the cross-track portion defines an aperture extending from the first surface to the second surface. The device also includes a dielectric portion disposed in the aperture such that the dielectric portion defines a ridge waveguide having a lowest-order mode cut-off frequency that is less than the frequency of incident optical energy used to heat the recording medium.

Abstract: A tool for reducing torque on work string, eg for gas or oil production, comprises an upper clamp (2), a lower clamp (3) and connection means (4), the three components formed as a unitary structure (1). The tool also comprises bearing means, preferably made from an elastomeric compound, and an annular body (7) (see FIG. 4) held in place over the connection means by the clamps. The clamps may comprise spigots (5) for retaining the connection means. In a preferred embodiment the annular body is in two semi-annular components connected at one end to allow them to pivot, and the other end comprises mating castellations for receiving a fastening pin. The annular body may comprise a number of replaceable wear pads (14) which may be made of bronze or an elastomer. The unitary structure of the tool enhances the integral strength and efficiency of the clamps.

Abstract: A lens for focusing collimated light. The lens includes a single, optically transmissive material having an aspherical focusing surface and a second surface, such that collimated light incident on the aspherical focusing surface is focused in a near-field region of the second surface.

Abstract: A method of making c-axis perpendicularly oriented barium hexaferrite thin films by the crystallization of amorphous barium hexaferrite on a platinum underlayer is provided. Using a thin underlayer of platinum, barium hexaferrite films can be deposited by conventional rf diode or magnetron sputtering. Such deposition may be performed at room temperature, after which excellent c-axis perpendicular orientation can be achieved by rapid ex-situ annealing. The c-axis perpendicular orientation can also be achieved through in-situ annealing.

Abstract: This invention relates to a method and apparatus for compensating the output signal of a reflection type eddy current probe so as to minimize the change in the phase shift of the probe output signal that otherwise would occur as a result of a change in the spacing of the probe from the surface of the metal sample being inspected or investigated.

Abstract: This invention relates to automatic gain control (agc) circuitry and more particularly to circuitry for supplying respective automatic gain control signals to an amplifier that repeatedly receives a given sequence of signals. Each one of the signals in each sequence is sampled and compared with a reference voltage in a respective feedback loop. The respective agc loops are coupled to the amplifier in a predetermined sequence to control the gain of the amplifier in a desired manner. The steps in this predetermined sequence are initiated by an external trigger and by the receipt of the signals to be controlled.

Abstract: A flexible tubular assembly having an outer tube and located therein an inner tube. One end of the inner tube is in communication with the locale of the nasal passages of a patient. The other end of the inner tube is provided with the safety connector at an end portion of the outer tube externally with respect to the outside of the connector through a wall thereof. The external connection includes a tubular nipple that is at an angle with respect to the connector and is the safety connector feature of the present invention.