Abstract: A setting tool for use in wells includes a mandrel formed with an interior combustion chamber. The setting tool further includes a barrel piston sized and configured to extend at least partially over an exterior of the mandrel and a shear device coupled to a portion of the mandrel and coupled to the barrel piston when in an in-line configuration. The mandrel includes an upper portion having a lead portion, an engagement portion, and a wrench-application portion. The wrench-application portion has a longitudinal length in the range of 1.5 to 3.0 to receive a wrench and avoid damage to the shear device. Other tools are disclosed.

Abstract: Provided, in one aspect, is a downhole magnetic debris removal apparatus. The downhole magnetic debris removal apparatus, in one aspect, includes a housing having a longitudinal axis, and a plurality of magnets arranged as one or more Halbach arrays of magnets coupled to the housing, the one or more Halbach arrays of magnets having a strong side and a weak side.

Abstract: An apparatus includes a first body, a second body, a shear pin, and a divider. The first body includes a coupling. The second body includes a cutter blade. The shear pin is configured to hold the position of the second body relative to the first body in an open position. The coupling is configured to couple the first body to the second body in a closed position. In the open position, the apparatus defines first and second flow paths for fluids and solids to pass through the apparatus. The first flow path is defined through the first body and through an inner bore of the divider. The second flow path is defined through the first body and through an annulus surrounding the divider. In the closed position, the second flow path is closed, such that solids remain in the annulus surrounding the divider.

Abstract: A wellbore gauge cutter apparatus includes a sampling body defining a central recess extending from an inlet at a first end to an outlet at a second end. The apparatus further includes a gauge cutter connected to the sampling body configured to dislodge particles from an inner wall of a wellbore. The sampling body includes an inner wall defining the central recess, a hollow cylindrical divider having a central aperture, a first flow path defined in the central aperture of the hollow cylindrical divider, a second flow path defined between an outer wall of the hollow cylindrical divider and the inner wall of the sampling body, and a fluid permeable screen arranged in the first flow path or the second flow The fluid permeable screen is configured to collect a portion the particles dislodged by the gauge cutter.

Abstract: A setting and retrieval mechanism for a well tool including a mandrel, a body lock ring disposed on the mandrel, a body lock ring engagement member engaged and disengagable with the body lock ring, and a setting load and retrieval sleeve disposed on the mandrel and having an engagement member support region and an engagement member release region. A method for retrieving a downhole tool including moving a setting and retrieval sleeve to position an engagement member release region of the setting and retrieval tool to allow disengagement of an engagement member with a body lock ring, placing a tensile force on the setting and retrieval sleeve, disengaging the engagement sleeve from the body lock ring under the impetus of the tensile force on the setting and retrieval sleeve, and releasing captured energy in the downhole tool by the disengaging and the tensile force on the setting and retrieval sleeve.

Abstract: A scale sampler plunger having an upper end and a downhole end for a plunger lift system in a tubing string comprising: a solid cylindrical member at the upper end of the scale sampler plunger configured to remove a plurality of contaminants in the tubing string; a lower sub at the downhole end of the scale sampler plunger threaded to the solid cylindrical member, wherein the lower sub comprises a first section threaded to a second section extending axially from the first section; wherein a fluid stream carrying solids flows from the tubing string into an entry opening located in the second section; a deflector disposed in a chamber in the lower sub, wherein the deflector causes the fluid stream carrying solids to deposit the solids in the chamber in the lower sub; and an anchor disposed in the entry opening, wherein the anchor is fastened to the deflector.

Abstract: An apparatus includes a gauge cutter, a lead impression block (LIB), a locking pin, and a locking device. The gauge cutter has a gauge cutter tubular body, a gauge cutter head, and an orifice. The LIB has an LIB body and an LIB head. The LIB is fixed in a first position within the orifice of the gauge cutter by being connected to an inner circumferential surface of the gauge cutter tubular body using a shear pin. The locking pin is disposed around the LIB body. The locking device is disposed around the inner circumferential surface of the gauge cutter tubular body and is configured to mate with the locking pin to hold the LIB in a second position within the gauge cutter. The second position includes a portion of the LIB body located within the orifice and the LIB head located outside of the orifice.

Abstract: A downhole apparatus comprises a sleeve, a tool string, a plug, a means for setting the plug wherein an upper portion of the sleeve is connectable to a lower portion of the tool string, and a lower portion of the sleeve is arranged to receive the plug and the means for setting the plug. A method of using the downhole apparatus is disclosed.

Abstract: A first sand accumulator may include a housing and an insert within the housing. The insert includes axially aligned outer and inner sleeves. In a first position, the outer and inner sleeves both have large flow ports that align to form a continuous flow path for fluid to flow through the sand accumulator such that a vortex flow forms in the sand accumulator. A second sand accumulator may include a housing disposed in line with a wellbore tubular and an insert disposed inside the housing such that insert forms a continuous end-to-end seal with a section of the wellbore tubular. An inlet section of the insert has an inlet port configured to permit fluid flow such that a vortex flow forms in the inlet section. A method of using a sand accumulator includes introducing process fluid entrained with sand to the sand accumulator.

Abstract: A fracturing method, to cause a crack in bedrock, includes installing a depressurizing device in a well in the bedrock, and depressurizing the inside of the well with the installed depressurizing device. The installing step includes installing, in the well, a connecting pipe, which is connected to the depressurizing device, and a packer, which is attached to the connecting pipe, and the depressurizing step includes shutting off a gap between the well and the connecting pipe, with the packer, and depressurizing a region in the well below the packer, with the depressurizing device.

Abstract: A collecting device for displacement in a tubing. The collecting device is extended in shape with a longitudinal axis and forms a leading portion with an entrance and an end portion. The device includes a wall extending from the leading portion to the end portion, a collecting chamber formed inside a portion of the wall, a filter positioned with the collecting chamber, a motor, a pump, and an outlet at the end portion, where the filter stocking provided with an open first end portion and a closed second end portion, and the open first end portion faces the leading portion, a and the filter stocking forms a receptacle. A method for emptying the collecting device is described.

Abstract: Methods and apparatuses are provided for clearing a wellbore using a component for milling and a component for suctioning within a wellbore. Obstructions such as ball frac seats, bridge plugs, or formation material can be milled within a wellbore. As a result, larger, unrestricted, diameters can be obtained within the liner/wellbore. The cleared wellbore can allow for various remedial tools to be run into the liner/wellbore. In addition, the milled particles can be suctioned/vacuumed up and can be pumped/pushed to surface in an underbalanced fashion. In some embodiments, this can be achieved by incorporating a bottom-hole pump or a venturi component into the bottomhole assembly. The system can be deployed using a spoolable single or multi-conduit coiled tubing system and can be configured as a well intervention or work-over technology. In some embodiments, the clearing equipment can be temporary or mobile.

Abstract: A well hole cleaning tool includes a plurality of tubular subcomponents arranged in a string-like fashion, having a plurality of flapper valves disposed above a notched collar, a wash pipe shoe, a bit and a mill. An upper stabilizer is disposed above a lower stabilizer which in turn is disposed above a sand screen. When in operation, the tool creates a vacuum at the lower end which facilitates flow of debris and waste water upward and out of the well hole.

Abstract: A hollow milling-bit defines a first interior flow passage. A junk catcher sub is connected to the hollow milling-bit and positioned between the hollow milling-bit and the uphole end. A junk recovery tube is connected to the junk catcher sub and positioned between the junk catcher sub and the uphole end. A reverse circulation diverter sub is connected to the junk recovery tube and positioned between the junk recovery tube and the uphole end. The reverse circulation diverter sub includes a ball seat configured to receive a ball. The first recirculation passage fluidically connects the interior flow passage to an outer surface of the tool. The second recirculation passage fluidically connects the interior flow passage to an outer surface of the tool. A catch basket that defines openings is connected to a downhole end of the reverse circulation diverter sub and positioned in the third interior flow passage in-line.

Abstract: A wellbore cleanout system including a first tubular, and a pump member including a stator and a rotor. The stator has a first end, a second end, an outer surface, and an inner surface defining an internal passage. The rotor is arranged within the internal passage and includes a first end portion connected to the first tubular and a second end portion. The rotor is coupled for rotation with the first tubular. A drag system including at least one drag member is fixedly mounted to the outer surface of the stator. A second tubular is connected to the second end of the rotor. The second tubular is coupled for rotation with the first tubular.

Abstract: A movable sleeve is actuated to cover eductor outlet ports in the event of loss of through flow. The eductor reduces pressure in the tool on one side of the sleeve as compared to hydrostatic on another side of the sleeve so that the sleeve is urged to move in an uphole or downhole direction to cover the eductor outlet ports. This movement reverses circulation direction through the housings in an effort to push debris off a clogged screen with reverse flow. To return the sleeve to its initial position the inlet to the device is inserted into debris and the surface pumps are started to create an unbalanced force on the sleeve to move it back to the original position free of the eductor outlet ports. The sleeve configuration can be reversed so that low pressure from a flow blockage urges the sleeve down to close the eductor ports.

Abstract: This invention relates to a junk catcher (2, 2?) releasably connected to a retrievable bridge plug (4, 4?) connectable to a setting tool (6) for joint deployment of bridge plug (4, 4?) and junk catcher (2, 2?) in a borehole (9) or a tubular in the borehole (9). Setting tool (6) extends through a fishing neck (12), a catcher tube (14), a flanged section (16), a valve chamber (18), a closable opening (20) and a portion of a setting sleeve (22, 22?) of junk catcher (2, 2?). Valve chamber (18) comprises a valve (50) arranged to close closable opening (20) after retrieval of setting tool (6) from junk catcher (2, 2?). The junk catcher (2, 2?) is connected to bridge plug (4, 4?) by at least one shear bolt (27, 38). Bridge plug (4, 4?) comprises a plug fishing neck (32, 32?) facing junk catcher (2, 2?), and bridge plug (4, 4?) comprises an equalizing channel (71) in a mandrel (7).

Abstract: A completions fluid loss control system for incorporation into upper completion hardware. The system allows for the avoidance of a dedicated intermediate completion installation in advance of upper completion delivery to a lower completion at a formation interface. The system includes a unique cup packer and flow regulation arrangement such that annular fluid thereabove may be isolated away from space below the system while at the same time allowing annular fluid therebelow to bypass the system. As such, the upper completion may be advanced toward the installed lower completion while maintaining well control at the noted formation interface.

Abstract: A basket is attached below a retrievable bridge plug used during the pressure testing of a well to verify integrity prior to fracturing operations. After the pressure integrity test above the plug, the plug is released and retrieved and a series of balls of increasing diameter are dropped on increasingly larger ball seats to allow shifting sleeves to an open position from the heel of the well toward the surface to sequentially frac in that direction. If any segments of the sealing element break off they are captured and removed in the basket that has flow through opening small enough to retain the debris and allow flow through the basket during removal. The basket is slotted for through fluid flow and can have a breakaway for the support rod if the basket sticks when the plug is removed.

Abstract: A subterranean debris catcher swirls the incoming debris laden stream by putting grooves or spiral projections on the inside of the inlet pipe. The solids come out of openings in the side of the inlet pipe or the solids can exit near the top either directly into the enclosed solids holding volume as the liquid exits straight out or the solids can be discharged out the end of the inlet pipe into the bigger open space defined by the housing. In the latter case the inside housing wall can have a screen or vanes that slow down the solid particles as the fluid continues to a housing exit and eventually to an exit screen before being discharged to either go to the surface or recirculate back along the outside of the tool to the inlet pipe while picking up additional debris.

Abstract: A downhole tool for removing debris from fluid flowing through the downhole tool comprises a screen member in sliding engagement with an inner wall surface of the tool. As the screen member becomes blocked, it moves from a first or initial position to a second or actuated position which causes a pressure change detectable at the surface of the wellbore. The pressure change causes the debris blocking fluid flow through the screen member to fall off the screen member thereby allowing an increase in fluid flow through the screen member. As a result, the screen member returns to its initial position and fluid again flows through the screen member for capturing by the screen member.

Abstract: A power head for connection in a tubing string suspended in a subterranean location in a wellbore is useful for removing debris from the wellbore. When the power head is in the closed position, well fluids pumped down the tubing string will flow through the power head. When the power head is moved to the open position by dropping a actuator ball onto a seat in the power head, the power head creates flow down along the annulus to circulate debris laden well fluids into a catch apparatus such as a catch basket or screen. In the open position, nozzles and the eductor create the reverse flow.

Abstract: A debris removal device for subterranean use features a debris laden inlet tube within a housing to define a debris collection space at the lower end of the housing. An eductor draws the debris laden fluid to the top of the inlet tube where the flow stream is returned to a downhole direction with discrete passages formed between the housing and the inlet tube by spaced parallel plates. The plates feature extending tabs on diametrically opposed lower ends of the plates. As a result flow heading back downhole can release debris and turn back uphole in passages defined between the outside of the plates and the inside wall of the housing. The tabs allow the flow turning uphole to make a greater radius turn because of a crossing over effect created by the tabs. There is less turbulence and narrower width to the flowing stream going uphole.

Abstract: A nozzle assembly including a nozzle. The nozzle has an elongated body. The elongated body has a nozzle end at one end and a connection portion at another end. A joint section is connected with the connection portion. The joint section allows the nozzle to move axially and radially when an axial force is applied to the nozzle end.

Abstract: A system and method for jet perforating within a well are disclosed. A jet perforating tool configured to be lowered inside a production tubing string comprises a tool body with a passage, an inlet in the upper section, perforating jets in the lower section, and a stepped outer diameter configured to seat on a production tubing string restriction such as a seat nipple. The tool may be lowered into the production tubing string without the need to trip the production tubing string in and out of the wellbore.

Abstract: A basket catcher for catching debris such as broken metal bands from an oil borehole casing as production tubing is withdrawn. The basket catcher has a collar that includes a series of spring-tensioned blades directed upwardly catch debris as the basket is withdrawn through the casing, preventing the debris from occluding the borehole.

Abstract: A downhole tool for removing debris from a wellbore comprises a body having a bore, a collection member, and a means for creating a hydraulic barrier within a wellbore annulus. The hydraulic barrier within the wellbore annulus restricts upward movement of a debris laden fluid within the wellbore annulus causing the debris laden fluid to be directed toward the collection member. Thus, the hydraulic barrier facilitates removal of debris from the wellbore.

Abstract: A downhole tool for removing debris from fluid flowing through the downhole tool uses a screen member and wiper member, the wiper member having at least one window disposed through the inner and outer wall surfaces of the wiper member. Either the screen member or the wiper member is rotatable such that rotation of the screen member or the wiper member causes debris disposed on the outer wall surface of the screen member to fall-off the screen member. At least one direction port disposed at either the upper end of the screen member or the upper end of the wiper member causes rotation of the screen member or wiper member when fluid flows through the downhole tool.

Abstract: A subterranean debris catcher takes in debris laden fluid at a lower end. The inlet flow is induced with an eductor whose discharge goes around the housing to the lower end inlet for the debris. The eductor suction induces flow into the lower end of the housing as well. Incoming debris goes up an annular space around the collection receptacle and turns to pass through a bladed wheel that imparts a spin to the flowing stream. The flow direction reverses from up before the wheel to down through a tube after the wheel. The solids are flung to the tube periphery and the fluid reverses direction to go back up to a screen before reaching the eductor suction connection. The debris swirls down an open bottom tube and is collected in a housing surrounding the down tube.

Abstract: A device with an overshot including a first part with an elongated body adapted to be connected to a hoisting line in one end and with a tubular opening arranged/designed to receive a spearhead in the other end. The overshot further includes a second part with a scissor like mechanism including two lifting dogs arranged to pivot around a common pivot pin. The lifting dogs are connected via a biasing unit and the elongated body includes a central, axially extending slot. The scissor like mechanism is arranged with the common pivot pin sliding in the slot between a first end position where the biasing unit is arranged to close the lifting dogs such that a spearhead received in the tubular opening is locked and a second end position where an opener including an opening pin is arranged to force the lifting dogs open against the force of the biasing unit, such that a spearhead received in the tubular opening is released.

Abstract: The present invention relates to hydraulic jars which include a jar body; a spindle axially movable within the jar body and coupled to the jar body by means of a helical splined coupling; the spindle being connectable to a pipe string and the stuck object; a cylinder concentrically placed within the jar body with a radial gap, and having chambers for filling with a work fluid, the chambers being separated by a piston and fluidly connected by a channel, wherein the channel is provided by a back valve. The piston is axially movable within the cylinder, and is connectable to the spindle by means of a tractive rod, and to the body by means of a compensative rod. The piston is further provided with elastic split compression rings having initial gaps equal or close to zero.

Abstract: A downhole retrieval tool for engaging and retrieving an object from a wellbore includes a mandrel and a grapple having a contracted position and an expanded position. In the expanded position, the grapple engages the object for retrieval. The grapple is operably associated with an expansion member disposed on the mandrel to facilitate movement of the grapple between the contracted and expanded positions. The expansion member is releasably connected to the mandrel. In the event that the downhole tool and object, once secured to each other, are unable to be retrieved from the wellbore, the expansion member can be released from the mandrel which, in turn, causes the grapple to release from the object so that the downhole tool can be removed from the wellbore. A stored energy member facilitates movement of the grapple from the contracted position to the expanded position.

Abstract: A subterranean debris catcher swirls the incoming debris laden stream by putting grooves or spiral projections on the inside of the inlet pipe. In some embodiments the solids come out of openings in the side of the inlet pipe and in others the solids can exit near the top either directly into the enclosed solids holding volume as the liquid exits straight out or the solids can be discharged out the end of the inlet pipe into the bigger open space defined by the housing. In the latter case the inside housing wall can have a screen or vanes that slow down the solid particles as the fluid continues to a housing exit and eventually to an exit screen before being discharged to either go to the surface or recirculate back along the outside of the tool to the inlet pipe while picking up additional debris.

Abstract: A downhole tool for removing debris from a wellbore comprises a mandrel and a shroud disposed around a portion of the mandrel. The mandrel includes at least one mandrel port in fluid communication with a mandrel bore. The shroud includes a cavity and a shroud port. Debris laden fluid is pulled into the shroud cavity by flowing fluid through the mandrel bore, out the mandrel port, into the shroud cavity, and through the shroud port. The debris-laden fluid is pulled into the shroud cavity due to a pressure differential created by the flow of the fluid through the mandrel port and out of the shroud port. As the debris laden fluid flows into the shroud cavity, the debris is captured within the tool.

Abstract: A bottom hole assembly for engaging and removing an object within a wellbore comprises a cutting tool at a lower end. Continued engagement of the cutting tool with the object is facilitated by an axial compression device disposed within the bottom hole assembly below the anchor of the bottom hole assembly. The axial compression device comprises a compressed position and an expanded or extended position. As the object is being cut or abraded, the axial compression device moves from the compressed position toward the expanded position so that a continued downward force is transferred to the object by the bottom hole assembly.

Abstract: A downhole tool for removing debris from fluid flowing through the downhole tool comprises a screen member in sliding engagement with an inner wall surface of the tool. As the screen member becomes blocked, it moves from a first or initial position to a second or actuated position which causes a pressure change detectable at the surface of the wellbore. The pressure change causes the debris blocking fluid flow through the screen member to fall off the screen member thereby allowing an increase in fluid flow through the screen member. As a result, the screen member returns to its initial position and fluid again flows through the screen member for capturing by the screen member.

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 grapple device is secured to a mill to allow relative rotation between them. The grapple has an outward bias to allow it to grip the packer bore or an extension from the packer. The mandrel has a wedge adjacent its lower end and torque fingers that fit between grapple segments when relative longitudinal movement occurs between the mandrel and the grapple assembly. The grapple assembly has a left hand thread so that it comes out of the packer if the mandrel engages the grapple assembly in a manner for tandem rotation. The torque fingers on the wedge on the mandrel support the grapple fingers over their length as rotation to the right removes the grapple assembly from the packer bore. Reverse circulation takes away the cuttings into the mill bore where they are separated from the reverse circulating fluid.

Abstract: A subterranean debris catcher swirls the incoming debris laden stream by putting grooves or spiral projections on the inside of the inlet pipe. The solids come out of openings in the side of the inlet pipe and in others the solids can exit near the top either directly into the enclosed solids holding volume as the liquid exits straight out or the solids can be discharged out the end of the inlet pipe into the bigger open space defined by the housing. In the latter case the inside housing wall can have a screen or vanes that slow down the solid particles as the fluid continues to a housing exit and eventually to an exit screen before being discharged to either go to the surface or recirculate back along the outside of the tool to the inlet pipe while picking up additional debris.

Abstract: A retrieval tool and method for retrieving a remote tool with a threaded connection from a remote location. The retrieval tool includes a rotational drive member which rotates an attachment sub having a complimentary threaded portion. An articulated shaft assembly permits the attachment sub to move laterally and angularly with respect to the axis of the rotational drive member. A fluid conduit supplies fluid pressure for releasing the remote tool.

Abstract: A downhole tool for use in a wellbore having a tool body with a blade assembly slidably mounted thereon and movable between a retracted and an outwardly extended position. The blade assembly is biased towards the retracted position and movable with an actuating force to the extended position. The tool includes an indexer constructed and arranged to facilitate movement of the blade assembly.

Abstract: A downhole debris recovery tool including a ported sub coupled to a debris sub, a suction tube disposed in the debris sub, at least one magnet disposed in the debris removal tool, and an annular jet pump sub disposed in the ported sub and fluidly connected to the suction tube. A method of removing debris from a wellbore including the steps of lowering a downhole debris removal tool into the wellbore, flowing a fluid through a bore of an annular jet pump sub, jetting the fluid from the annular jet pump sub into a mixing tube, displacing an initially static fluid in the mixing tube through a diffuser, thereby creating a vacuum effect in a suction tube to draw a debris-laden fluid into the tool, flowing the debris-laden fluid past at least one magnet disposed in a debris housing, and removing the tool from the wellbore is also disclosed.

Abstract: A downhole tool for removing debris from fluid flowing through the downhole tool comprises a screen member and wiper member, the wiper member having at least one window disposed through the inner and outer wall surfaces of the wiper member. Either the screen member or the wiper member is rotatable such that rotation of the screen member or the wiper member causes debris disposed on the outer wall surface of the screen member to fall-off the screen member. At least one directional port disposed at either the upper end of the screen member or the upper end of the wiper member causes rotation of the screen member or wiper member when fluid flows through the downhole tool.

Abstract: A method for removing fines and debris from a downhole wellbore in a formation, including introducing a tubing string having a downhole debris removal tool disposed substantially near the lower end of the tubing string into the downhole wellbore; positioning the downhole debris removal tool substantially proximal to the fines and debris; circulating fluid through the downhole debris removal tool for disintegrating the fines and debris; and collecting the fines and debris in the downhole debris removal tool for removal out of the downhole wellbore.

Abstract: Disclosed are systems and methods for remote actuation of a downhole tool. One system includes a work string providing a flow path therein, a downhole tool coupled to the work string, at least one actuation device operatively coupled to the downhole tool and configured to act on the downhole tool such that the downhole tool performs a predetermined action, and an optical computing device communicably coupled to the at least one actuation device and configured to detect a characteristic of a substance in the flow path and trigger actuation of the at least actuation device when the characteristic is detected.

Abstract: The debris collection device operates on an eductor principle with motive fluid delivered from the surface into an eductor housing inlet. The eductor outlet goes into a surrounding annular space and splits with some flow going to the mill below to direct cuttings into the passage in the housing. The cuttings remain in the housing and the flow continues through a screen in the housing passage before reaching the eductor inlet. An auxiliary inlet is normally closed and opened with a reduced flow entering through the mill. The opening of the auxiliary inlet drops the surface pressure delivered to the eductor to act as a surface signal that a plugged or low debris laden inlet flow exists.

Abstract: An assembly for removing debris and/or conducting a wellbore operation may include a mandrel, a sliding sleeve rotationally coupled to the mandrel, and a flushing sleeve coupled to the sliding sleeve. A releasable connection may temporarily prevent axial movement between the sliding sleeve and the mandrel. A downhole tool may be coupled to the mandrel to conduct the wellbore operation. The flushing sleeve may be hydraulically actuated to an extended position ahead of the downhole tool. A method of removing debris from a wellbore and conducting a wellbore operation may include lowering an assembly into the wellbore, supplying pressurized fluid into the wellbore using the assembly to remove debris from the wellbore, and moving a downhole tool to a position where at least a portion of the downhole tool is disposed outside of the assembly to conduct the wellbore operation.

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 downhole magnet tool comprises a top sub having an inner bore terminating in a downhole facing open end, the inner bore defining a centralizer receptacle of smaller width than a width of the downhole facing open end, a mandrel terminating upwardly in a centralizer stem, the centralizer stem being fitted in the centralizer receptacle of the top sub, and a magnet mounted on a downhole facing surface of the mandrel. A method of assembly of a downhole magnet tool comprises mounting a magnet on the mandrel and inserting the centralizer stem into the centralizer receptacle.

Abstract: An activating mechanism for controlling the operation of a downhole tool in a drill string and which is intended to be housed in a portion of the drill string upstream of the downhole tool, in which: the activating mechanism has a first mode in which it allows through-flow of drilling fluid to the downhole tool and a second mode in which through-flow of fluid is blocked; and the activating mechanism has a number of through-flow ports permitting through-flow of drilling fluid in said first mode of the mechanism and which are capable of being blocked by launching a number of flow blocking activator balls down the drill string and which each are of such size and shape that they can block access to said through-flow ports in order to activate the mechanism to the second mode and thereby adjust the downhole tool from one mode of operation to another.