Abstract: An embodiment of the apparatus includes a housing having a first flow bore and a second flow bore, the first flow bore having a drilling fluid flowing therein, a device disposed in the second flow bore to receive a fluid flow, and a diverter disposed between the first and second flow bores, the diverter having a first position preventing the drilling fluid from flowing into the second flow bore and a second position allowing a portion of the drilling fluid to flow into the second flow bore and through the device. Another embodiment includes a variable second position directing the drilling fluid into the second flow bore at a variable flow rate. A further embodiment includes a drill collar as the housing and a power generation assembly as the device to receive the fluid flow. Embodiments of a method of diverting a fluid flow in a downhole tool include diverting a portion of a first fluid flow to a second flow bore, and further varying a flow rate of the fluid to the second flow bore.

Abstract: Aspects of the invention provide control systems and methods for directional drilling. One aspect of the invention provides a system for controlling a first module, a second module, and a third module. The system includes: an inlet configured to receive fluid from a fluid source; a first double-stage valve; and a second double-stage valve. The first double-stage valve is actuatable to a first position wherein fluid from the inlet flows through the first double-stage valve to the second double-stage valve and a second position wherein fluid from the inlet flows through the first double-stage valve to the third module. The second double-stage valve is actuatable to a first position wherein fluid flows from the first double-stage valve to the first module and a second position wherein fluid flows from the first double-stage valve to the second module.

Abstract: An apparatus for drilling a borehole in a well is provided. The apparatus comprises a tubular conveyance system; a drilling system connected to one end of the tubular conveyance system and comprising a bottom hole assembly; and a flow diverter positioned in the tubular conveyance system and comprising a first flow channel configured to receive fluid from inside the conveyance system and at least two side flow channels configured to direct fluid from the first flow channel out of the tubular conveyance system. The fluid flow between the first flow channel and each side flow channels is controlled by a valve which is operable to divert fluid out of the tubular conveyance system or to maintain the fluid in the tubular conveyance system.

Abstract: A device and the relative are described, for the insertion of a new drilling string-element into a drilling-string essentially including a short pipe-shaped body (C) having, at opposite ends thereof, a device suitable for screwing the body onto drill pipes, in which two valves are housed, of which one valve (A) is radial to said short body, interceptable from the outside by means an adaptor and equipped with a suitable safety plug, the other valve (B) being axial with respect to the body.

Abstract: A drill and a separator apparatus and a method of prolonging bearing life are described, the separator apparatus being suitable for separating an air/water mixture into discrete air and water streams during drilling of a blast hole. The separator apparatus includes a separator body which is adapted to be installed at a distal or lower region of a drill string and when installed at the distal or lower region forms one or more separation chambers or reservoirs, each separation chamber or reservoir comprising an inlet adapted to receive the air/water mixture, a first outlet in fluid communication with a drill bit for releasing air thereto and a second outlet in fluid communication with a wall of the blast hole and disposed in the distal or lower region of the drill string to release water separated from the air/water mixture in a region adjacent the drill bit.

Abstract: A flexible/rigid drilling assembly that can be flexible enough to bend around and into a curved hole form a vertical well to the horizontal with a short horizontal hole extension. When the flexible/rigid drilling assembly is placed in the short horizontal hole extension it can be converted to a rigid assembly and provide stability for a drill bit on its end to drill a straight horizontal out into an oil, gas or water. High static drilling fluid pressure with low compression force on the flexible/rigid drilling assembly is used to keep it in a flexible configuration while being placed in the short horizontal hole extension. Then the flexible/rigid drilling assembly is rotated to release the high static drilling fluid pressure. With the high static drilling fluid pressure released and with the high compression forces required to operate the drill bit the flexible/rigid drilling assembly transition into its rigid configuration and provide stability for a drill bit in drilling a straight horizontal drain hole.

Abstract: A drill bit is disclosed that in one configuration may include at least one cutter on a face section of the bit and at least one opening proximate the at least one cutter configured to discharge fluid under pressure onto the formation to create a fluid cushion between the drill bit and the formation during a drilling operation. An actuation device associated with the drill bit may be utilized to provide fluid under pressure to the at least one opening.

Abstract: Apparatus and a method for adding and removing tubulars whilst containing the pressure within a drill string and/or maintaining circulation of drilling fluid down a drill string using a diverter sub which is able to open up to mud flow from a side mud port and close off the flow of mud from above the drill string with or without continuous rotation of the drill string.

Abstract: An apparatus (10) for keeping a down hole drilling tool vertically uses a pendulum (36). The pendulum (36) controls flow from outlets (34) of drilling fluid chambers (30), providing drilling fluid to centralizer (24) activating pistons (26) acting upon centralizer blades (24). When the outer housing (12) deviates from a vertical orientation, the pendulum (36) swings by force of gravity to assume an angularly offset pivotal position. This adjusts the hydraulic pressure in one or two of the outlets (34) for one or two of the drilling fluid chambers (30) resulting in a change in the hydraulic force acting upon one or two of the pistons (26) causing one of the centralizers (24) to change their position to urge the outer housing (12) back toward the vertical position until the pendulum (36) again assumes the concentric pivotal position and the balanced pressure equilibrium in the drilling fluid chambers (30) is restored.

Abstract: A drill pipe having a tubular body through which is provided a main bore, a side port provided in an exterior surface of the body, a side bore extending through the body from the main bore to the side port, and a valve member which is movable between a closed position in which fluid flow through the side bore is substantially prevented and an open position in which fluid flow through the side bore is permitted, wherein the movement of the valve member between the closed position and the open position comprises translational movement, and the valve member is located at least predominantly within the side bore.

Abstract: A downhole tool includes a tubular body having an upper connection and a lower connection and an axial borehole therethrough, wherein the upper and lower connections are configured to connect to a drilling assembly. The downhole tool further includes at least one expandable component coupled to the tubular body and configured to selectively extend radially therefrom and an actuation mechanism configured to selectively extend the at least one component in response to a change in a circulating fluid pressure in the axial borehole.

Abstract: A technique is presented for providing a double-barrier to formation fluids during drilling operations with a concentric drill string having an inner bore and an annulus. A primary flow control system is used to provide a first barrier to formation fluids in the inner bore and annulus of the drill string. A backup flow control system is used to provide a second barrier to formation fluids. The backup flow control system comprises a backup inner bore shutoff valve and a backup annulus shutoff valve. The backup inner bore shutoff valve is dropped from the surface through the inner bore of the drill string. The backup inner bore shutoff valve has spring-biased tabs that are configured to extend outward to contact an inner surface profile of the inner bore of the drill string. The backup annulus shutoff valve may be provided with the profile to receive the spring-biased tabs from the backup inner bore shutoff valve.

Abstract: A flushing device (20) comprising an inner sleeve (21), axially slidable relative to an outer sleeve (23). The inner (21) and outer (23) sleeves cooperate to define an inner passage (32) for the flow of a fluid, and are permanently coupled such that there is substantially no rotational movement between the two sleeves. The inner passage (32) has an inlet (22b) and an outlet (22a). The outer sleeve (23) has a plurality of flushing outlets (33) which, when the flushing device (20) is in an open condition allow fluid to be diverted from the inner passage (32). The flushing device (20) also comprises an indexing mechanism (80) which indexes between a first position, wherein the plurality of flushing outlets (33) are blocked from the internal passage (32) such that the flushing device (20) is in a closed condition, to a second position, wherein the plurality of flushing outlets (33) register with the internal passage (32) such that the flushing device (20) is in the open condition.

Abstract: In one aspect of the present invention a drill bit has a jack element with a distal end extending beyond a working face. A porting mechanism within the bore comprises first and second discs contacting along a flat interface. The first disc is attached to a turbine which is adapted to rotate the first disc with respect to the second disc. The discs comprise a first set of ports adapted to align and misalign with each other as the first disc rotates. The first set of ports is adapted to route a drilling fluid to extend the jack element.

Abstract: A downhole device used to divert fluid flow out of a work string into an annulus. The downhole device is activated by the movement of a plurality of pistons within the downhole device. Fluid flow through a restriction of the downhole device creates an increase in fluid pressure causing the movement of the pistons. The pistons move a flow tube between various locations within the device. In one location, the flow tube prevents fluid flow to the annulus while in another location the flow tube allows fluid flow to be diverted into the annulus. The downhole device may include a locating sleeve having a continuous j-track allowing the flow tube to be selectively retained at the various locations within the downhole device. Fluid flow through the downhole is used to cycle the device between diverting fluid flow to the annulus and forcing fluid flow down the work string.

Abstract: Well jet device comprises a packer mounted on a pipe string provided with a central channel embodied therein and jet pump. The pump has channels supplying a working medium to a nozzle, removing the media mixture and supplying a medium pumped from the well, respectively. Said nozzle is connected to the annular space by the channels and the channel is connected to the pipe string internal cavity through the channel on the side, where the diffuser of the pump enters and exits. A working medium flow switch is arranged in the body. An annular channel communicating with the channel via the channel and the nozzle is above said abutment flange and the steady bush comprises bypass holes and mounting seat for mounting a sealing unit with a hole for passing a logging cable with instruments therethrough or for arranging a depression insert provided with a return valve.

Abstract: In one aspect of the present invention a tool string comprises a jack element substantially coaxial with an axis of rotation. The jack element is housed within a bore of the tool string and has a distal end extending beyond a working face of the tool string. A rotary valve is disposed within the bore of the tool string. The rotary valve has a first disc attached to a driving mechanism and a second disc axially aligned with and contacting the first disc along a flat surface. As the discs rotate relative to one another at least one port formed in the first disc aligns with another port in the second disc. Fluid passed through the ports is adapted to displace an element in mechanical communication with the jack element.

Abstract: A circulating sub is run in with the circulating port closed. A dart blocks a central passage and moves two concentric pistons in tandem to open the circulation port while retaining the dart. The outer piston shoulders out in the circulation port open position. A second dart lands on the first and with applied pressure moves the inner piston relative to the shouldered outer piston to close the circulation port and only then discharge both darts. Subs can be used in tandem as long as higher located subs accept larger darts than lower subs and preferably the two darts for each sub are the same size. The ejected darts can be used to pressure actuate a downhole tool like a packer.

Abstract: A downhole device used to divert fluid flow out of a work string. The downhole device may be located at any point along a work string at which it may be necessary to divert the fluid flow to the annulus. The downhole device may be activated and deactivated by inserting a single deformable dart into the work string. The device catches the dart blocking fluid flow through the work string. Increased fluid pressure activates the device, which diverts the fluid flow out of the work string into the annulus. A locating sleeve with a continuous j-track allows the device to be retained in activated position. The dart is adapted to deform under a predetermined amount of fluid pressure allowing the dart past the device and returning fluid flow through the work string. The downhole device may be activated multiple times without removing the downhole device from the wellbore.

Abstract: A down hole air diverter having a first opening in communication with the central passageway of a drillstring; a second opening in communication with the well bore annulus; and a means to control the flow of pneumatic fluid between the first opening and the second opening. The means to control the flow further includes a first sealing means and a first biasing means to control the first sealing means. The first sealing means allows communication with the well bore annulus when the well bore annulus pressure exceeds the first biasing means pressure and prevents communication when the bias pressure exceeds the bore annulus pressure. A second sealing means prevents communication with the drillstring when the pressure from the second sealing means chamber exceeds the first opening pressure and allowing communication when the first opening pressure exceeds the chamber pressure.

Abstract: A pressure relief valve assembly useful for relieving fluid pressure in a pressurized device, the assembly in certain aspects including a valve body with an inlet passageway in fluid communication with an outlet passageway, a valve member for selectively controlling fluid flow from the inlet passageway to the outlet passageway, a wear member around a portion of an entrance end of the outlet passageway, the valve member movable within the wear member, the wear member extending into the outlet passageway a distance less than the length of the outlet passageway; and, in certain aspects, the wear member threadedly secured to the valve body.

Abstract: A downhole tool for use within a well comprising a body having an external diameter smaller than the diameter of the well so as to form an annular gap between the body and the interior surface of the well. A first downhole fluid passage having an upper inlet and a lower outlet is provided in the body. At least one secondary fluid passage extending between the first downhole fluid passage and the annular gap is provided at the body. A sleeve member is provided at the body and adapted to move between a first position in which said at least one secondary fluid passage is closed and a second position in which said at least one secondary fluid passage is open. The sleeve member is maintained at one or both of the first and second positions upon rotation of the body within the well.

Abstract: A by-pass tool is provided which has a large bore throughflow passage when in an inactive drilling mode, and which is capable of being activated upon launching of an activation dart from the surface, to an active mode in which drillstring fluids can be diverted to a by-pass port. The by-pass tool includes a casing, a by-pass port for diverting drillstring fluids when the tool is in the active mode, and an axially slidable member placed within the casing to slide between blocking and release positions with respect to the by-pass port. The slidable member may be moved to the release position by the dart to bring ports in the slidable member into registry with the by-pass port. This slidable member may also return to its blocking position and thereby cause the tool to revert to its inactive mode upon wireline retrieval of the dart.

Abstract: A by-pass tool for incorporation in a drillstring is adjustable between an inactive mode in which it allows fluid flow lengthwise of the drillstring during normal drilling operation, and an active by-pass mode when drilling is to be interrupted. The tool includes an outer casing, an axially displaceable sleeve within the casing, a valve seat associated with the sleeve and arranged to receive an activating ball, and by-pass port means in the casing. The valve seat receives the activating ball when the ball is launched from the surface and down the drillstring. The valve seat displaces the sleeve axially to adjust the tool from the inactive mode to the active by-pass mode. The by-pass port means allows a locking ball to partially block the port means and thereby initiate flushing-out of any drillstring fluid debris above the valve seat via the port means.

Abstract: The present invention comprises a drilling tool assembly for drilling oil comprising a bit release subassembly, a test sleeve that is removable to open and close flow ports, and a profile nipple.

Abstract: A drilling assembly (2) comprises upper (4) and lower (6) drill strings with a fluid passage (80) therethrough for distributing fluid to a bottom hole assembly (10). The upper drill string (4) has an upper end (11) connectable to a drilling apparatus (13) and fluid source (16) and a lower end (18) with an attached casing expander unit (20) that communicates the fluid passage (80) of the upper (4) and lower (6) drill strings. An upper end (22) of the lower drill string (6) is formed from a casing string (24) telescoped over the casing expander unit. A constriction (31) connects the casing string (24) with the rest of the lower drill string (6). A flow restriction device (35) in the lower drill string acts to control fluid flow through the fluid passage.

Abstract: A well drilling bit having a bit body attachable to a tubular drill string, which bit body is internally provided with a passageway providing fluid communication, when the drill string is attached to the bit body, between the interior of the drill string and the exterior of the bit body; a closure element for selectively closing the passageway; and one or more chip-making elements, wherein the chip-making elements has one or more roller-cones, wherein the closure element is releasably connectable to the bit body, and outwardly movable from a closing position to an opening position, and wherein the closure element includes at least one of the roller-cones.

Abstract: An oil and gas well drilling system is provided that includes a torque drive system having an output shaft and a drill string rotated by the torque drive system. An instrumented internal blowout preventer valve is connected between the torque drive system output shaft and the drill string. The valve includes a valve housing, and one or more measurement devices mounted to the valve housing for measuring desired drill string drilling parameters during an oil and gas well drilling operation.

Abstract: A three-part sub-assembly comprising a wire line retrievable spear. The spear having two fluid chambers. A diverter valve having a truncated, inverted cone valve seat is preferably threaded into the interior of the spear. A diverter valve stem, having back-to-back cones is located within the interior of the spear/diverter valve combination, with one of the cones having a linear extension which prevents the first cone from completely seating against the valve seat within the interior of the spear. The spear/diverter valve assembly and a spring-loaded piston is placed within the interior of the cylinder and utilizes an adjustable ring within the interior of the cylinder as an adjustment for varying mud weights.

Abstract: A fluid flow switching device for a drill string comprises a tubular member having a port (4). A sleeve member is slidable within the tubular member between a first position in which a port (3) thereof is in alignment with the port (4) and a second position in which the port (4) is obstructed. A plurality of fingers are connected to the sleeve member (2). Each finger defines one segment of a closure member that is closed when the fingers are pivoted inwardly and open when the fingers are pivoted outwardly. An operating surface is positioned within the tubular member, and the fingers are axially slidable thereover as the sleeve member is moved between the first and second positions to close and open the segmented closure.

Abstract: A fluid flow actuated downhole tool is configurable in at least a first tool configuration and a second tool configuration. The tool comprises a tubular housing and an activating sleeve, the housing being adapted to catch the sleeve when the sleeve is dropped from surface and the engagement of the sleeve with the housing permitting actuation.of the tool between the first and second tool configurations. A flow restriction is provided for permitting fluid flow actuation of the tool when the activating sleeve has been caught in the body.

Abstract: The present invention relates to downhole apparatus and particularly but not exclusively, to multi-cycle circulating subs used during downhole drilling operations. Apparatus is provided comprising a piston (42) slidably mounted in a body (4) between positions in which at least one aperture (40) in the body is opened and closed. Movement of the piston (42) is controlled by a pin (86) secured to one of the body and a control member, and a control groove (52) in which a portion of the pin is received formed in the other of the body and control member. An arrangement of elements (32, 76) respectively connected to the control member and body is such that, as the control member moves axially, increasing lengths of said elements locate adjacent one another so as to provide resistance to relative rotation in at least one direction of the control member and body. The relative rotation is rotation which presses the control member against the control groove.

Abstract: A valve assembly connects into a drill string for opening and closing at least one inner passage within the drill string of the drill string. The valve assembly includes an annular valve assembly carried in an annular passage that moves between the open and closed positions in response to downward fluid pressure from the surface through the annular passage. The valve assembly also includes an inner valve assembly carried in an inner passage of the drill string. The inner valve assembly is a two-way valve that is actuated between open and closed positions by pressure pulses from the surface through the inner passage. The valve assembly can be used within coiled tubing.

Abstract: A valve assembly connects into a drill string for opening and closing a passage within the drill string. The valve assembly has an inner valve member for opening and closing an inner passage of the drill string. The valve member moves between the open and closed positions in response to axial movement of the drill string. Lifting the drill string causes the upper portion to move upward relative to the lower portion, bringing along with it the valve member, while the valve sleeve remains stationary with the lower portion, opening the valve. The valve assembly can include an annular valve assembly for opening and closing an annular passage located around the inner passage. The annular valve assembly is opened and closed by increasing the pressure in the annular passage above the annular valve assembly.

Abstract: A method for optimizing drilling fluid hydraulics when drilling a well bore is disclosed. The drilling fluid is supplied by a surface pump through a drill string to a drill bit. The method has the step of adjusting the flow rate of a surface pump and a fluid pressure drop across the drill bit while drilling such that the drilling fluid hydraulics are optimized for a given drilling condition. In order for the flow through all the devices in the drill string to also be optimized, the flow through the devices is adjusted, thereby setting the pressure drop and the fluid flow rate through each device. As required for the overall system, the flow from the surface pump is increased or decreased as necessary.

Abstract: A downhole tool (10) for selectively circulating fluid in a borehole is disclosed. The tool operates via the use of a combination of deformable drop balls (36) and smaller hard drop balls (40). In use a deformable drop ball (36) moves a sleeve (20) exposing a radial port (30,32) to provide fluid circulation radially from the tool. The smaller drop ball (40) can then obstruct the radial port (32,30) and by the increased pressure the deformable drop ball (36) is extruded through the tool. The resulting pressure differential as the drop ball (36) moves causes the sleeve (20) to rise, releasing the smaller drop (40) ball and closing the radial port (32,30). The process can be repeated to selectively circulate fluid through the tool.

Abstract: A boring apparatus is described which comprises a substantially hollow vessel with a fixed base and a rotatable base. The rotatable base is provided, at its circumference, with at least one side cutter which rotatable with the rotatable base from a first position, in which the at least one side cutter serves to cover a respective opening provided in the vessel wall, to a second position, in which the opening in the vessel wall is exposed.

Abstract: A by-pass tool to be incorporated in a drill string, in combination with an activating ball assembly operative to adjust the tool between an activated mode and a de-activated mode. The tool has a valve seat engageable by the activating ball assembly to move its sleeve to a by-pass mode which diverts drilling mud from flowing through the housing to a by-pass flow through the by-pass port. The activating ball assembly has a deformable ball of a size sufficient to engage and to be held captive by the salve seat and a weight attached to the ball and operative to assist in movement of the assembly under the action of gravity to engage the ball with the valve seat. The weight has smaller transverse dimensions that the ball so that it moves downwardly through the valve seat and pulls the ball into engagement with the valve seat.

Abstract: A high torque and high capacity rotatable center core and floatable sealed body apparatus with universal ram applications. The apparatus includes a central core assembly, connected between a swivel on its upper end and the work string below, with the central core assembly having a central passageway therethrough. The apparatus further includes a first outer assembly, having a central bore for slidably engagement around a portion of the central core assembly. In one embodiment, a second outer assembly is included, with the second outer assembly having a central bore for slidably engaging around a portion of the central core assembly above the first outer assembly. A pair of opposing transverse bores is contained within both of the first and second outer assemblies, corresponding to a pair of transverse bores in the central core assembly.

Abstract: Method and apparatus for drilling a well bore in a hydrocarbon formation using concentric drill string having an inner pipe and an outer pipe defining an annulus there between. A drilling means such as an air hammer or a rotary drill bit and driving system is provide at the lower end of the concentric drill string and drilling medium is delivered through the annulus or inner pipe for operating the drilling means to form a borehole. Drilling medium, drilling cutting and hydrocarbon are removed from the well bore by extracting the drilling medium, drilling cutting and hydrocarbon through the other of the annulus or inner pipe.

Abstract: The apparatus (10) for delivering grease through the individual string (12) includes a tubular member (14) for holding a supply of grease, a piston (16) sealing slidable through the tubular member (14) and a first valve (18) coupled to a downstream end (20) of the member (14). Valve (18) has a body (22) provided with orifices (24) and a collar (26) slidably mounted over an end of the body (22) and biased to a sealing position in which it seals the orifices (24). Piston (16) is initially located above an upstream end (28) of the tubular member (14). Apparatus (10) is slid through the drill string (12) until collar (26) abuts a stub, typically a core bit retained at the end of the string. Fluid pressure is then applied to apparatus (10) by pumping water or mud down the drill pipe (12). This forces collar (26) to be displaced in covering the orifices (24).

Abstract: A rotary steering apparatus including a drill string, a drill bit, a main body connected at one end to the drill string and at another end to the drill bit, a sleeve extending around the main body such that the main body is freely rotatable within the sleeve, and a locking member affixed to the main body and interactive with the sleeve. The sleeve has at least one protruding pad extending outwardly therefrom so as to bear against a well bore. The locking member serves to lock the sleeve relative to the main body such that the sleeve rotates correspondingly with a rotation of the main body. The locking member locks the sleeve onto the main body relative to an increased flow rate of fluid through the interior passageway of the main body. The locking member includes a flipper pivotally connected to the main body so as to extend into the longitudinal passageway and a spring resiliently connected to the flipper so as to urge the flipper into the interior passageway with a desired spring rate.

Abstract: Downhole flow pulsing apparatus comprises a housing (14) for location in a drillstring, the housing (14) defining a throughbore to permit passage of fluid through the housing. A valve (27, 30) is located in the bore and defines a flow passage (29, 31). The valve includes a valve member (27) which is movable to vary the area of the passage (29, 31) to provide a varying fluid flow therethrough. A fluid actuated positive displacement motor (15, 16) is associated with the valve member (27). In a preferred embodiment, the apparatus is provided in combination with a drill bit (5) and a pressure responsive device, such as a shock-sub (3), which expands or retracts in response to the varying drilling fluid pressure created by the varying flow passage area. The expansion or retraction of the shock-sub (3) provides a percussive effect at the drill bit.

Abstract: A down-hole tool comprises a generally tubular body for connection in a drill string, the body typically having an upper tubular member and a lower tubular member interconnected to be axially secured and relatively rotatable, and a frangible element securing the upper and lower members together rotationally and adapted to rupture at a predetermined load

Abstract: The by-pass valve has a selective control already available to control the movement of a piston which is part of the main stream by-pass valve which diverts fluid from the pipe string bore to ports in the outer wall for projection of the fluid stream into a well.

Abstract: A tubular tool body carried at the end of a drilling rig top drive is received within a drill string being used as a landing string to position casing in a wellbore. External threads on the tool body can be mated with the box threads of the drill string to secure the top drive and drill string together for simultaneous drill string movement and fluid circulation. An annular seal carried about the tool body engages and seals with the internal wall of the drill pipe to prevent drilling fluid leakage when the tool body is received within the drill pipe without thread engagement. The tool has an internal check valve that opens to allow back flow of drilling fluid that may be displaced from the drill pipe as the pipe is lowered into the well. The check valve prevents standing fluid in the top drive from spilling onto the rig floor when the tool is withdrawn from the drill string.

Abstract: A mudsaver valve for use in well drilling operations includes an elongated tubular main body supporting a tubular mandrel-like mudsaver closure member therein for movement between valve open and closed positions. A coil spring is disposed in the main body member and is engageable with the mudsaver closure member to bias the mudsaver closure member in a valve closed position. The mudsaver closure member includes an axial passage formed therein and ports opening from the axial passage to the exterior of the mudsaver closure member. The mudsaver closure member is engageable with an annular resilient packoff element and is pressure biased to move to an open position wherein the ports pass through the annular packoff element to allow fluid to flow through the valve.

Abstract: The diverter valve is carried in a housing that serves as a length of drill string. A selector valve is actuated by selective mud flow control signals from the surface and can close to build internal pressure to move a poppet to open a by-pass channel. Positive resilient seals are carried inside a protective sleeve until the principal openings are closed, then the seal is deployed to stop leakage.

Abstract: A mudsaver valve for insertion into the upper end of a well casing includes an elongated cylindrical valve body member having a central bore for receiving an elongated generally tubular valve closure member for movement in the body bore between valve closed and open positions. Passages in the closure member open to the outer surface thereof and spaced apart seal members mounted on the closure member prevent fluid flow out of the valve when the closure member is disposed in a closed position in the body. The body supports plural circumferentially spaced spring biased drag blocks or radially deflectable leaf or bow spring members which are engageable with the casing to support the body stationary in the casing so that the closure member may be reciprocated with respect to the body between valve open and closed positions.

Abstract: A preferred novel circulating sub includes an electric motor, hydraulic intensifier, connecting rod, valve sleeve, valve plug, and angled nozzles. Upon activation of the circulating sub the electric motor drives the valve sleeve over the valve plug, causing a flow of drilling fluid to exit the angled nozzles. Upon deactivation of the circulating sub, the electric motor removes the valve sleeve from the valve plug, allowing the flow of drilling fluid to once again flow to the drill bit. Because the electric motor is reversible, the circulating sub can be repeatedly activated and deactivated.