Abstract: A device for transporting a tool string down a bore comprises a single unitary part mandrel comprising a connection at each end of the mandrel for in-line connection of the device in a tool string and a single unitary part annular body rotationally mounted to the mandrel to rotate relative to the mandrel about a longitudinal axis of the mandrel or tool string. A pair of wheels is rotationally mounted to the annular body to rotate relative to the mandrel on a rotational axis perpendicular to the longitudinal axis of the tool string. A collar is releasably coupled to the mandrel to allow for assembly of the annular body onto the mandrel from one end of the mandrel when the collar is disassembled from the mandrel and axially retain the annular body on the mandrel when the collar is assembled to the mandrel.

Abstract: A device for transporting a sensor assembly along a bore comprises an axle extending through a body of the device and mounted to rotate on a rotational axis perpendicular to a central longitudinal axis of the device. A wheel fixed to each end of the axle. The device has a conduit through the body for accommodating an electrical conductor to extend through the device from end-to-end. The conduit comprises a non-linear portion extending around the axle between the ends of the device.

Abstract: A centraliser comprises a mandrel, a first support member, a second support member, and a plurality of arm assemblies connected between the first and second support members. Each arm assembly comprises a first arm pivotally connected to the first support member at a first pivot axis and a second arm pivotally connected to the second support member at a second pivot axis, and the first and second arms pivotally connected together at a third pivot axis. The mandrel comprises a plurality of facets spaced apart around an outer surface of the mandrel to rotationally key the first and/or second support member to the mandrel, and each arm assembly is arranged so that the third pivot axis is located on a first side of a plane coincident with a central axis of the device and the first and second pivot axes are located on an opposite second side of the plane.

Abstract: The disclosure relates to a sensor transportation apparatus to convey an elongate sensor assembly through a wellbore. The sensor transportation apparatus comprises at least one engagement structure to connect the sensor transportation apparatus to the sensor assembly, and a pair of wheels arranged to rotate about an axis of rotation substantially perpendicular to a longitudinal axis of the sensor assembly when the transportation apparatus is connected to the sensor assembly, and an orientation structure comprising at least one orientation projection, in a transverse outline of the sensor transportation apparatus a said orientation projection extending between the pair of wheels so that the shortest distance between a centre of mass of the elongate sensor assembly and the wellbore wall is when the pair of wheels are in contact with the wellbore wall.

Abstract: A centraliser comprises arm assemblies pivotally connected between first and second support members. Each arm assembly comprises a first arm and a first pivot joint having a first pivot axis, a second arm and a second pivot joint having a second pivot axis, the first and second arms pivotally attached together via a third pivot joint having a third pivot axis. The arm assemblies are arranged in diametrically opposed pairs. In some embodiments the first arm comprises a fork section to position the first pivot axis coincident with the central longitudinal axis of the device, or so that the first pivot axis and the third pivot axis are positioned on opposite sides of a plane coincident with the central longitudinal axis of the device.

Abstract: A guide device for a tool string to guide the tool string down a wellbore, the guide device comprising: a coupling to connect the guide device to an end of a tool string, a mandrel and a tip at a leading end of the mandrel, a centralising device supported by the mandrel, and a joint (a flexible joint or articulation joint) between the mandrel and the coupling allowing angular displacement of the mandrel relative to the tool string so that the tip can displace from a longitudinal axis of the tool string.

Abstract: The disclosure relates to a carriage apparatus for carrying a tool string down a wellbore in a wireline logging, and an orientation apparatus and hole finder device for a wireline logging tool string. In some embodiments the carriage includes a protection structure which extends longitudinally around a wheel of the apparatus to thereby prevent a side of the wheel from contacting a wall of the wellbore. In some embodiments an orientation apparatus and hole finder are arranged so that the orientation apparatus orientates the hole finder device in the wellbore so that a tip of a nose section of the hole finder is elevated above a low side of the wellbore by a height and offset from and above a longitudinal axis of the tool string.

Abstract: A device for centering a sensor assembly in a bore comprises a plurality of arm assemblies connected between first and second support members. Each arm assembly comprises a first arm pivotally connected to the first support member by a first pivot and a second arm pivotally connected to the second support member by a second pivot joint. A beam is connected between the first and second arms, the first arm pivotally connected to the beam by a third pivot joint and the second arm pivotally connected to the beam by a fourth pivot joint. A wheel is rotationally mounted to the beam on a rotational axis located axially between the third and fourth pivot joints to contact a wall of the bore in use. A third arm is pivotally connected to the first support member by a fifth pivot joint having a fifth pivot axis axially spaced from the first pivot axis, and is pivotally connected to the beam by a sixth pivot joint having a sixth pivot axis.

Abstract: A sensor transportation apparatus for conveying a sensor assembly through a wellbore comprises at least one engagement structure to connect the sensor transportation apparatus to the sensor assembly, at least one axle, a bearing connected to the axle, and a wheel connected to the bearing and provided with a shaft seal to prevent or reduce debris from the wellbore entering the bearing, and a lubrication delivery system to provide a lubricant to the bearing at a pressure which is greater than ambient wellbore pressure. The lubrication system comprises a bellows formation, and the apparatus comprises a housing to contain the lubricant, the housing in fluid communication with the bearing, the bellows formation sealingly mounted to the housing with at least a portion of the bellows received within the housing.

Abstract: A sensor transportation apparatus comprises at least one engagement structure to connect the sensor transportation apparatus to the sensor assembly, a pair of wheels arranged to rotate about an axis of rotation substantially perpendicular to a longitudinal axis of the sensor assembly when the transportation apparatus is connected to the sensor assembly, and an orientation structure comprising the pair of wheels and an orientation projection extending between the pair of wheels. Lateral extremities of the pair of wheels and the orientation projection together define a curve extending circumferentially around a portion of the circumference of the elongate sensor assembly. A rotational centre of the curve is offset from a central axis of the elongate sensor assembly and a rotational axis of the pair of wheels is above the central axis of the elongate sensor assembly when the sensor transportation apparatus is substantially horizontal.

Abstract: A device for transporting a sensor assembly in a bore comprises a plurality of wheels azimuthally spaced apart around a longitudinal axis of the device. Each wheel presents a radial extremity of the device. The wheels are moveably supported to move between a minimum outer diameter of the device and a maximum outer diameter of the device. An adjustable stop mechanism is configured to pre-set the maximum outer diameter of the device within a range of maximum outer diameters so that the device is configurable for use in a pre-determined range of bore diameters. One or more spring elements bias the wheels radially outwards and are preloaded to provide a radial force to the wheels when at the pre-set maximum outer diameter.

Abstract: A device for centering a sensor assembly in a bore comprises a first support member and a second support member axially spaced apart along a longitudinal axis of the device, and a plurality of arm assemblies connected between the first and second support members. Each arm assembly comprises a first arm pivotally connected to the first support member by a first pivot joint having a first pivot axis, a second arm pivotally connected to the second support member by a second pivot joint having a second pivot axis, a third arm connected between the first and second arms, the third arm pivotally connected to the first arm by a third pivot joint having a third pivot axis, and the third arm pivotally connected to the second arm by a fourth pivot joint having a fourth pivot axis.

Abstract: A device for centering a sensor assembly in a bore comprises a mandrel, a first support member and a second support member axially spaced apart along a longitudinal axis of the mandrel. The first and second support members adapted to move axially along the mandrel. A plurality of arm assemblies are spaced circumferentially apart around the longitudinal axis of the device and connected between the first and second support members. Each arm assembly comprises a first arm pivotally connected to the first support member by a first pivot joint having a first pivot axis, a second arm pivotally connected to the second support member by a second pivot joint having a second pivot axis, and the first and second arms pivotally connected together via a third pivot joint having a third pivot axis.

Abstract: A sensor transportation apparatus to convey a sensor assembly through a wellbore. The apparatus comprising has an engagement structure to connect the sensor transportation apparatus to the sensor assembly, and one or more wheels arranged to rotate about an axis of rotation substantially perpendicular to a longitudinal axis of the sensor assembly when the transportation apparatus is connected to the sensor assembly. An orientation structure defining a form having a transverse outline which has a rotational center, wherein the rotational center is offset from a centroidal axis of the elongate sensor assembly.

Abstract: A logging tool assembly comprises an elongate sensor assembly, a plurality of sensor transportation apparatuses for transporting the elongate sensor assembly through a wellbore, and an orientation structure. The sensor transportation apparatuses are spaced apart along the elongate sensor assembly. Each sensor transportation apparatus comprises an engagement structure to connect the sensor transportation apparatus to the elongate sensor assembly and prevent relative rotation between the sensor transportation apparatus and the elongate sensor assembly, and one or more pairs of wheels arranged to rotate on an axis of rotation substantially perpendicular to a longitudinal axis of the elongate sensor assembly. The axes of rotation of the pairs of wheels of said transportation apparatuses are parallel. The orientation structure is connected to the elongate sensor assembly to prevent relative rotation between the orientation structure and the elongate sensor assembly.

Abstract: A sensor transportation apparatus to convey a sensor assembly through a wellbore. The apparatus comprising has an engagement structure to connect the sensor transportation apparatus to the sensor assembly, and one or more wheels arranged to rotate about an axis of rotation substantially perpendicular to a longitudinal axis of the sensor assembly when the transportation apparatus is connected to the sensor assembly. An orientation structure defining a form having a transverse outline which has a rotational centre, wherein the rotational centre is offset from a centroidal axis of the elongate sensor assembly.

Abstract: A sensor transportation apparatus to convey a sensor assembly through a wellbore. The apparatus comprising has an engagement structure to connect the sensor transportation apparatus to the sensor assembly, and one or more wheels arranged to rotate about an axis of rotation substantially perpendicular to a longitudinal axis of the sensor assembly when the transportation apparatus is connected to the sensor assembly. An orientation structure defining a form having a transverse outline which has a rotational center, wherein the rotational center is offset from a centroidal axis of the elongate sensor assembly.

Abstract: A sensor transportation apparatus to convey a sensor assembly through a wellbore. The apparatus comprising has an engagement structure to connect the sensor transportation apparatus to the sensor assembly, and one or more wheels arranged to rotate about an axis of rotation substantially perpendicular to a longitudinal axis of the sensor assembly when the transportation apparatus is connected to the sensor assembly. An orientation structure defining a form having a transverse outline which has a rotational centre, wherein the rotational centre is offset from a centroidal axis of the elongate sensor assembly.