Abstract: A circulation tool includes a tubular outer body having a main bore and at least one flow port in a wall thereof, and a valve seat assembly including a valve body, a valve member, and locking elements are movably mounted within the outer body main bore. The valve seat assembly is biased towards a first position in which flow through the outer body flow port is prevented and the locking element is in the extended position, restricting passage of the valve member along the valve body bore and out of the valve body. The valve seat assembly is movable to a second position in which the locking element is in the retracted position, permitting passage of the valve member along the body bore and out of the body. The valve seat is also movable to a third position in which flow through the outer body flow port is permitted.

Abstract: A clamp holds two members together. The first member includes a recess into which a fastener is located. A bore is provided to the recess to allow a tool to be used to operate the fastener. The second member is arranged to accept the fastener and so join the members. The recess and bore are sized to prevent release of the fastener through the bore. In this way, the fastener cannot easily be removed or lost when the clamp is in use and is tamperproof. The clamp is used to hold portions of a sleeve around a body of the tool, and to hold scraper blades and/or brushes to the body.

Abstract: A downhole isolation valve for testing the integrity of a tubular within a wellbore includes a tubular body with an axial through bore having a reduced diameter portion defining a valve seat and a ledge; an inner sleeve, with a closed end configured to seal within the valve seat, a shoulder spaced from that closed end, and a radial outlet positioned between the shoulder and the closed end; wherein in use the inner sleeve is selectively moveable within the bore at a predetermined pressure between a closed position, in which there is no flowpath through the bore, and an open position, in which the closed end is positioned beyond the valve seat to expose the radial outlet to the through bore beyond the valve seat and provide a flowpath through the bore of the outer tubular body.

Abstract: A method of drilling and cleaning a wellbore while rotating the drill string after full drilling depth is reached without running the drill string out the bore to install a clean up work string is disclosed wherein a drill string having a drill bit at one end includes at least one near bit selectively activatable cleaning tool (10, 11, 12) mounted within the length of the drill string, said cleaning tool having a cleaning member (18) adapted to be moved from a close fitting stowed configuration within a recess (17) to a deployed configuration upon a body of the tool, wherein the cleaning member has magnets (19, 43) for use in positioning thereof, and compact tools for scraping, milling and brushing with improved resistance to ingress of detritus, debris and formation particulates are disclosed.

Abstract: A downhole cleaning tool for cleaning a casing is provided with a diverter cup assembly (102) including a housing (126) and a resilient swab cup (105) slidably mounted on a tubular body (120) with an increased external diameter portion 128 defining at either end upper and lower limit stops (130, 132), and sized to make provision for a gap (136) which allows a sliding movement of the swab cup such that only one of limit stops (130, 132) engages to always pull the swab cup via optional bearings (134) at each extremity of the sliding travel according to whether the tool is being run in hole or pulled out of the hole. This means that the swab cup is not compressed into a squat oversize shape susceptible to contact damage, and is naturally drawn out to tend towards an elongate shape in either direction of tool motion.

Abstract: A method of drilling and cleaning a wellbore includes providing a drill string having a drill bit and a cleaning tool with selectively activatable cleaning members; drilling a wellbore using the drill bit while maintaining the cleaning members in a deactivated position; and pulling the drill string from the wellbore with the cleaning members in an activated position, to thereby clean the wellbore. A corresponding cleaning tool includes a body having a bore running therethrough, a sleeve located within the bore, the sleeve including a ball seat and the sleeve being biased in a first direction, and a plurality of selectively activatable cleaning members mounted for repeated movement relative to the body between activated and deactivated positions.

Abstract: A cleaning tool (1) for use in cleaning ferrous material from a wellbore has a magnetic cleaning element (14) mounted to a tool body (2) within a slot (5) using a releasable concealed interference fit fastener assembly (15) comprising a fastener member having a head (16), and a shank (17) with a configured end (18) and a deformable fastener ring (20) adapted to fit closely over the shank, and a press-fit collar (21) adapted to deform the deformable fastener ring upon the configured end of the shank when assembled, and wherein the respective head and collar are each flanged to permit an interference fit with a corresponding contact surface of the tool body around said slot.

Abstract: A pressurization tool comprises a body for connection to a tubular by box, and pin, and providing for flow of fluid by way of a throughbore of varying cross-section to form chambers. A lower chamber accommodates a spring that contacts a shoulder providing a reaction surface for compression of the spring under applied force. The chamber merges into intermediate chamber that accommodates a movable index sleeve that cooperates with an index pin inserted through the wall of the tool body. Associated with the upper part of the index sleeve is a valve seat assembly, positioned to abut the index sleeve and moveable therewith, said valve seat assembly being configured to receive a plug or ball, and in one unpressurised configuration, is located in a wider chamber that permits fluid flow around the assembly.

Abstract: This invention relates to well cleaning methods and apparatus. In particular, this invention relates to a method of drilling and cleaning a wellbore. In one embodiment of the invention, a method of drilling and cleaning a wellbore (12) is disclosed. The method comprises the steps of providing a drill string (10) having a drill bit (28) and a cleaning tool (24) with selectively activatable cleaning members (34); drilling a wellbore using the drill bit while maintaining the cleaning members in a deactivated position; and pulling the drill string from the wellbore with the cleaning members in an activated position, to thereby clean the wellbore. A corresponding cleaning tool is also disclosed.

Abstract: A clamp (10) for holding two members together. The first member includes a recess into which a fastener is located. A bore is provided to the recess to allow a tool to be used to operate the fastener. The second member is arranged to accept the fastener and so join the members. The recess and bore are sized to prevent release of the fastener through the bore. In this way, the fastener cannot easily be removed or lost when the clamp is in use and is tamperproof. Embodiments of a downhole tool are described where the clamp is used to hold portions of a sleeve around a body of the tool, and to hold scraper blades and/or brushes to the body.

Abstract: A clamp (10) for holding two members together. The first member includes a recess into which a fastener is located. A bore is provided to the recess to allow a tool to be used to operate the fastener. The second member is arranged to accept the fastener and so join the members. The recess and bore are sized to prevent release of the fastener through the bore. In this way, the fastener cannot easily be removed or lost when the clamp is in use and is tamperproof. Embodiments of a downhole tool are described where the clamp is used to hold portions of a sleeve around a body of the tool, and to hold scraper blades and/or brushes to the body.

Abstract: A method of controlling fluid flow through a hollow body, uses a ball seat assembly (12) comprising a hollow body (14) defining a bore (16) and a ball seat (18) mounted said bore, the ball seat being moveable relative to the bore between an extended position in which the seat defines a restriction to passage of a ball (20) along the bore, and a retracted position spaced axially along the bore from the extended position and in which position passage of the ball along the bore is permitted. A subsequent reduction in the fluid pressure force acting on the ball seat facilitates movement of the seat from the extended position shown in the upper half of FIG. 1, to the retracted position shown in the lower half of the Figure, to permit passage of the ball through the bore to thereby re-open fluid flow through the bore.

Abstract: A downhole flow control tool 1, includes a flow control member in the form of a sleeve 8, and comprises a main body 2 having a longitudinal internal bore 3 extending therethrough, an upper end 4 having a box section 6, and a lower end 5 with a pin section 7, which enable connection of the tool 1 into a work string. The flow control sleeve 8 is mounted for movement relative to the bore 3 between at least a closed and one of several open positions. The tool body 2 includes several flow ports extending through a wall of the body 2 and spaced around a circumference of the body 2. The tool provides multiple fluid flow control options for directing and splitting fluid flow for example during a drilling operation to clear settled cuttings by suitable location of the tool.

Abstract: A method of preparing a wellbore for production includes running a wellbore clean-out string, including a cement evaluation tool and a wellbore cleaning tool, into a wellbore, acquiring data relating to at least one property of a cement bond of the wellbore, using the cement evaluation tool, and simultaneously cleaning the wellbore, using the wellbore cleaning tool, as the clean-out string is run into the wellbore in order to acquire first and second sets of data while running the string into the wellbore. The first and second sets are combined to form first and second logs of cement bond, which are used to produce an enhanced log of the cement bond.

Abstract: A downhole isolation valve for testing the integrity of a tubular within a wellbore includes a tubular body (12) with an axial through bore (14) having a reduced diameter portion (29) defining a valve seat (16) and a ledge (17); an inner sleeve (18), with a closed end (22) configured to seal within the valve seat, a shoulder (28) spaced from that closed end, and a radial outlet (24) positioned between the shoulder and the closed end; wherein in use the inner sleeve is selectively moveable within the bore at a predetermined pressure between a closed position, in which there is no flowpath through the bore, and an open position, in which the closed end is positioned beyond the valve seat to expose the radial outlet to the through bore beyond the valve seat and provide a flowpath through the bore of the outer tubular body.

Abstract: A wellbore cleaning assembly is run into a wellbore to be cleaned on a work string. The cleaning assembly comprises a number of cleaning elements for cleaning a wall of the wellbore; and an oscillator coupled to the at least one cleaning element by a force transmission element, for generating an axial oscillating movement of the at least one cleaning element relative to the work string.

Abstract: A downhole cleaning tool for cleaning a casing is provided with a diverter cup assembly (102) including a housing (126) and a resilient swab cup (105) slidably mounted on a tubular body (120) with an increased external diameter portion 128 defining at either end upper and lower limit stops (130, 132), and sized to make provision for a gap (136) which allows a sliding movement of the swab cup such that only one of limit stops (130, 132) engages to always pull the swab cup via optional bearings (134) at each extremity of the sliding travel according to whether the tool is being run in hole or pulled out of the hole. This means that the swab cup is not compressed into a squat oversize shape susceptible to contact damage, and is naturally drawn out to tend towards an elongate shape in either direction of tool motion.

Abstract: A pressurization tool comprises a body for connection to a tubular by box, and pin, and providing for flow of fluid by way of a throughbore of varying cross-section to form chambers. A lower chamber accommodates a spring that contacts a shoulder providing a reaction surface for compression of the spring under applied force. The chamber merges into intermediate chamber that accommodates a movable index sleeve that cooperates with an index pin inserted through the wall of the tool body. Associated with the upper part of the index sleeve is a valve seat assembly, positioned to abut the index sleeve and moveable therewith, said valve seat assembly being configured to receive a plug or ball, and in one unpressurised configuration, is located in a wider chamber that permits fluid flow around the assembly.

Abstract: Work string-mounted cleaning tool and a method of assembling such tools using a quick release for the cleaning element. Oblong pad element has a curved upper surface with slots to receive work surface segments. Opposite edge has a part-circular recess with part-circular peripheral lip around an upper edge of the recess. A retainer fastening component in the recess has a core with socket adapted to receive a driving tool. The retainer is sized to permit it to rotate when mounted within the recess. Roll pins are provided for use in locating the fastener component in predetermined rotational configurations in relation to the recess. Shear pin is provided to inhibit unintended rotation of the fastener component, and to lock the retainer for normal use of the cleaning tool. Shearing of the shear pin permits disassembly of the tool.

Abstract: A device for use in retrieving debris from a well, including an elongate body; a main bore extending part way along a length of the body; an opening towards a lower end of the body; a main fluid chamber in the body in fluid communication with the main bore; a flow restriction provided in the main bore, through which fluid flows from the main bore and into the main fluid chamber; at least one chamber outlet for directing fluid from the main fluid chamber into an annulus defined between the device and a well borehole wall; a return flow passage extending between the body opening and the main fluid chamber, for return flow of fluid from the annulus to the main fluid chamber, to facilitate retrieval of debris from the well; and at least one fluid exit, for flow of fluid out of the device.