Abstract: A mudsaver valve with retrievable inner sleeve. An annular piston is secured to a first end of the inner sleeve such that movement of the annular piston results in movement of the inner sleeve between a valve closed position and a valve open position. In the valve closed position radial outlet passages of the inner sleeve are blocked by a flow control sleeve. In the valve open position the inner sleeve is moved relative to the flow control sleeve so that the radial outlet passages are no longer blocked. The inner sleeve is maintained in the valve closed position until pump pressure acting upon the annular piston overcomes a biasing force of a biasing spring causing the inner sleeve to be carried by the annular piston to the valve open position.

Abstract: Method and apparatus for drilling a directional or horizontal wellbore in a hydrocarbon formation using concentric drill string having an inner pipe and an outer pipe defining an annulus there between. A bottomhole assembly comprising a directional 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 directional drilling means to form a borehole. Exhaust drilling medium, drilling cutting and hydrocarbon are removed from the wellbore by extracting the exhaust drilling medium, drilling cutting and hydrocarbon through the other of the annulus or inner pipe.

Abstract: A hydraulic accumulator for use in a drill string having a fluid passage for supply of fluid to a hydraulic drill string tool is provided. The accumulator comprises a body provided with connecing means for connecting the accumulator to the drill string and an expansion chamber in fluid communication the fluid passage when the accumulator is connected to the drill string by the connecting means. The expansion chamber is expandable between a first volume and a second volume which is larger than the first volume. Further, the expansion chamber is provided with means for moving the expansion chamber from the first to the second volume upon a fluid pressure increase in the fluid passage and for moving the expansion chambe from the second to the first volume upon a pressure decrease in the fluid passage.

Abstract: A drilling fluid powered rotary drilling motor is mounted on the downhole end of a non-rotating fluid conducting drill string has a drill bit on its distal end and a plurality of fluid engaging, rotating elements coupled to at least one speed reducing planetary gear stage that converts the kinetic and pressure energies of the drilling fluid to mechanical power for rotating the drill bit. The drilling motor includes a lubricator, a drilling fluid filter, a pressure relief valve, a bypass valve and a check valve and is mounted with an output isolation coupling and a bearing package sized to withstand drilling load conditions.

Abstract: A roller cone drill bit is disclosed which includes a bit body having at least one leg depending from the bit body. The leg has a journal formed on it at a lower end. The bit body includes an air channel extending at least from an interior of the bit body to the seal area of the journal. A roller cone is sealingly, rotatably mounted on the journal. The cone has a plurality of cutting elements disposed on it. The bit includes a backflow valve disposed in the bit body, so that an intake end of the air channel is disposed upstream of the backflow valve. In one embodiment, the backflow valve is disposed in a connection end of the bit body, and the air channel includes a flow tube extending from the air passage in the bit body to the backflow valve so that its intake end is upstream of the backflow valve.

Abstract: A blowout preventer (10; 110) adapted to be included in a drill string (11; 111) to isolate a downhole portion of an annulus (14; 114) between the drill string and a borehole wall (12; 112). The blowout preventer has a tubular body (16; 116) and an expandable packer means (22; 122) having an inactive or unset position permitting fluidflow through the annulus (14; 114), and a released, active or set position closing the annulus (14; 114). The tubular body (16; 116) has a through-bore (18; 118) aligned with a bore of the drill string and passageways (30; 130) parallel to the through-bore (18; 118) with fluid inlet ports (32; 132) arranged in a manner to be sealingly covered by the packer means (22; 122) in its unset position, and uncovered upon release of the packer means (22; 122) to permit it to expand into its sealing position closing the annulus (14; 114).

Abstract: Flow control devices and associated control methods are described for use with hydraulic tools, such as those in a drill string. The described flow control device is typically incorporated into a drill string and is selectively operable in either a flow-through mode or a valve control mode. In the valve control mode, fluid pressure is increased or decreased within the drill string to selectively actuate a valve which is associated with the flow control device. In the flow-through mode, fluid pressure may be increased or decreased without operating the valve. Techniques are described for selectively moving the flow control device between the flow-through mode and the valve control mode. Wellbore fluid pressure readings provide signals to a rig operator for selectively moving the device in this manner.

Abstract: The steel drill string attached to a drilling bit during typical rotary drilling operations used to drill oil and gas wells is used for the second purpose as the casing that is permanently installed in the wellbore for the final completion of oil and gas wells. The rotary drill bit is attached to the drill string, the well drilled, and the well is completed leaving the drill bit attached to the drill string to make a steel cased well. The steel coiled tubing attached to a coiled tubing conveyed mud motor driven rotary drill bit is used to drill oil and gas wells that is used for a second purpose as the tubing that is permanently installed in the wellbore to make a tubing encased well for the final completion of oil and gas wells.

Abstract: A system usable with a subterranean well includes a tubing and a lubricator. The tubing is adapted to receive a drill string in a passageway of the tubing, and the lubricator is located downhole and is connected to the tubing. The lubricator is adapted to be remotely operable from a surface of the well to control fluid communication between the passageway located above the lubricator and a formation located beneath the lubricator. The lubricator may include a sleeve and controller. The controller selectively moves the sleeve into a passageway of a valve of the lubricator to protect the valve from a downhole fluid.

Abstract: The apparatus has a housing arranged to function as a length of drill string, including a fluid tight fluid conducting bore, with means at each end for connecting to a continuing drill string. The housing has two principal portions bearingly connected for rotation and axial constraint. A spring loaded one way clutch connects the two portions such that torque can be conducted therethrough in only one rotational direction. The clutch has one, spring loaded, axially moving element to actuate the clutch unless locked by optional provisions. The axial movement, optionally, actuates a valve in the fluid conducting bore to create a pressure drop in the fluid stream when the clutch is disengaged to provide a pressure signal that can be detected at the surface to indicate that the clutch is disengaged.

Abstract: Apparatus and associated methods are provided which facilitate underbalanced drilling and completion of wells. In a described embodiment of a well control valve, the valve is opened and closed when a drill string is displaced therethrough. A shifting device is carried on a drill bit and deposited in the valve when the drill string enters and opens the valve. The valve is closed and the shifting device is retrieved from the valve when the drill string is tripped out of the well. A packer hydraulic setting tool usable in conjunction with the well control valve in underbalanced completions is also provided.

Abstract: A method is disclosed for offshore drilling in which a bit is driven at a far end of a drill string, drilling fluid is injected into the drill string from surface drilling facilities, and drilling fluid passes through the far end of the drill string and flushes the borehole at the bit and entrains cuttings into the drilling fluid which circulates up the casing/drill string annulus. The drilling fluid drawn off near the mudline and is treated through a subsea primary processing stage to removing the cuttings from the drilling fluid. The treated drilling fluid is then returned to the surface with a subsea return pump system and passes to surface drilling facilities for injection and recirculation.

Abstract: Apparatus and methods for a deployment valve used with an underbalanced drilling system to enhance the advantages of underbalanced drilling. The underbalanced drilling system may typically comprise elements such as a rotating blow out preventer and drilling recovery system. The deployment valve is positioned in a tubular string, such as casing, at a well bore depth at or preferably substantially below the string light point of the drilling string. When the drilling string is above the string light point then the upwardly acting forces on the drilling string become greater than downwardly acting forces such that the drilling string begins to accelerate upwardly. The deployment valve has a bore sufficiently large to allow passage of the drill bit therethrough in the open position. The deployment valve may be closed when the drill string is pulled within the casing as may be necessary to service the drill string after drilling into a reservoir having a reservoir pressure.

Abstract: Apparatus and associated methods are provided which facilitate underbalanced drilling and completion of wells. In a described embodiment of a well control valve, the valve is opened and closed when a drill string is displaced therethrough. A shifting device is carried on a drill bit and deposited in the valve when the drill string enters and opens the valve. The valve is closed and the shifting device is retrieved from the valve when the drill string is tripped out of the well. A packer hydraulic setting tool usable in conjunction with the well control valve in underbalanced completions is also provided.

Abstract: The steel drill string attached to a drilling bit during typical rotary drilling operations used to drill oil and gas wells is used for the second purpose as the casing that is permanently installed in the wellbore for the final completion of oil and gas wells. The rotary drill bit is attached to the drill string, the well drilled, and the well is completed leaving the drill bit attached to the drill string to make a steel cased well. The steel coiled tubing attached to a coiled tubing conveyed mud motor driven rotary drill bit is used to drill oil and gas wells that is used for a second purpose as the tubing that is permanently installed in the wellbore to make a tubing encased well for the final completion of oil and gas wells.

Abstract: Apparatus and associated methods are provided which facilitate underbalanced drilling and completion of wells. In a described embodiment of a well control valve, the valve is opened and closed when a drill string is displaced therethrough. A shifting device is carried on a drill bit and deposited in the valve when the drill string enters and opens the valve. The valve is closed and the shifting device is retrieved from the valve when the drill string is tripped out of the well. A packer hydraulic setting tool usable in conjunction with the well control valve in underbalanced completions is also provided.

Abstract: A tool for incorporation in a drill string has an outer body (11, 12, 13) and a spool (17, 18, 19) rotationally and slidably mounted within the body. A cam groove (20) is formed on camming component (17) of the spool and interacts with pins (21) to cause uni-directional spool rotation through a number of pre-set angular positions as the spool is reciprocated. The valving component (18) of the spool is closed internally by wall (26) and has orifices (25) which come into and out of registration with body openings (29) as the spool is moved through its pre-set positions. When in registration, flow into the tool will leave the tool radially outwardly through openings (29); but when out of registration, the flow will be into chamber (28) of body central component (12), and back into the valving component (18) downstream of wall (26) through apertures (27).

Abstract: The steel drill string attached to a drilling bit during typical rotary drilling operations used to drill oil and gas wells is used for a second purpose as the casing that is cemented in place during typical oil and gas well completions. Methods of operation are described that provide for the efficient installation a cemented steel cased well wherein the drill string and the drill bit are cemented into place during one single drilling pass down into the earth. The normal mud passages or watercourses present in the rotary drill bit are used for the second independent purpose of passing cement into the annulus between the casing and the well while cementing the drill string into place during one single pass into the earth. A one-way cement valve is installed near the drill bit of the drill string that allows the cement to set up efficiently under ambient hydrostatic conditions while the drill string and drill bit are cemented into place during one single drilling pass into the earth.

Abstract: Apparatus and a method for killing a live well after activation of a well blowout preventer is described. This is achieved by providing apparatus in the form of a shear or kill sleeve (34) in a string (26) above a sub-sea test tree and which is located between the pipe rams (22, 24) and shear rams (18) of a blowout preventer (12). In the event that the shear rams (18) are activated and seal the string above the kill sleeve (34), the sleeve includes a pressure sensitive valve (84) which may be opened, by pressurising between the blowout preventer rams (18, 22), to permit fluid to be pumped from the blowout preventer (12) through the valve (84) and into the string (40), to choke or kill the well. After the well has been killed, the blowout preventer (12) may be opened to permit removal of the well tools. Embodiments of the invention are described.

Abstract: In a petroleum coke operation, a pilot hole is drilled in the coke by high pressure water emitting from downwardly directed nozzles in a drilling assembly. A full hole is eroded in the coke by diverting the high pressure water to a series of full hole nozzles in response to shutting off, and then resupplying, high pressure water to the drilling assembly. This conveniently converts pilot hole operations to full hole operations, which is the normal mode of cutting coke from a drum. Thus, the modes of operation are switched each time water is resupplied to the drilling assembly.

Abstract: A percussion drill bit includes a drill body having a fluid passage formed therein for conducting flushing fluid to a front drilling face of the drill bit. The fluid passage includes a main portion extending from a rear end of the bit and terminating short of the drilling face, and a plurality of branch lines extending from a front end of the main portion to the drilling face. Front and rear axially spaced seats are disposed in the main portion of the fluid passage. A check valve in the form of a ball is freely movable within the main portion of the fluid passage between contact with the front and rear seats. When the drill bit is oriented upwardly and no flushing fluid is supplied, the ball gravitates rearwardly into sealing contact with the rear seat so that no fluid can flow rearwardly past the rear seat. When flushing fluid is conducted, the flushing fluid pushes the ball forwardly, into non-sealing contact with the front seat and travels past the ball into the branch lines.

Abstract: A flapper valve assembly for use in a flow conduit in a subterranean well, the assembly having a valve closure member pivotally connected to a floating hinge assembly that slidably engages a sleeve comprising the valve seat. A strut assembly comprising circumferentially spaced struts pivotally connected to the valve closure member away from the floating hinge member and pivotally connected to a spring guide surrounding the flow conduit is also provided, and is biased to force the valve closure member toward the closed position.

Abstract: A casing shut-in valve system (74) having a flapper valve assembly (34) and a shift head assembly (76); the flapper valve assembly (34) having an upper body member (36), lower body member (38), flow sleeve (40), valve seat sleeve member (42), flapper (54), flapper hinge assembly (56), and a plurality of spring strut assemblies (58) disposed on opposite sides of the flapper hinge assembly; the shift head assembly (76) having key housing (134) with bit sub (144) rotatably mounted in bearing (152), a plurality of outwardly biased shift keys (80), and a load equalizer plate (138) at each end of the key housing; the shift head assembly (76) being adapted to selectively open or close the valve by engaging and moving the flow sleeve (40) between defined upper and lower positions, thereby controlling the movement of flapper (54) through an angle (128) of rotation that is less than 90 degrees, and preferably about 45 degrees.

Abstract: An adaptor for drilling strings has a head, sleeve and mounting block assembly to secure a drill bit to a drilling string. By reverse rotation of the drilling string, the sleeve is movable between a first position, where pressurized air from the drilling string is directed to the drill bit, to a second position, where the air is directed to the drill hole above the adaptor to clear debris from the hole. Teeth at both ends of the drill assist the adaptor to clear the hole as the drill string is rotated and retracted from the hole.

Abstract: A retrievable bridge plug apparatus, and associated methods, are provided for sealing the bore of a drill pipe string to control a well that is flowing out of control.

Abstract: A check valve sub assembly for series connection in a dual pipe string that extends downhole in a borehole for permitting flow of fluid in one direction through the annular passageway of the dual pipe string and preventing flow of fluid in the other direction. The check valve sub assembly includes an inner tube and an outer annular member for connection into series relationship respective to the inner and outer dual pipe so that fluid flow through the inner pipe is conducted through said inner tube and is maintained separate from the annulus.

Abstract: This invention relates to a rotary drill bit having a body with leg members, where each of the leg members has a projecting conical cutter receiving journal. Each conical cutter has an axially extending recess open at one end and is rotatably mounted on the journal by friction reducing bearings interior to the conical cutters. The drill bit has a main cavity which extends down the center of the drill bit body. A jet nozzle provides an exit opening at the bottom of the main cavity. At least one passageway extends to and opens into the main cavity at one end and extends to and opens into the bearings at the other end. The end of the at least one passageway which extends to the main cavity is provided with a plurality of openings and a plurality of deflectors associated with the openings. When a gas-liquid mixture is passed through the main cavity, the deflectors will cause an abrupt change in the gas flow direction.

Abstract: Device in impact machines. The device comprises a set of rods comprising a number of rods (6) which are journalled in a surrounding set of tubes (7) by means of elastic bushings (52, 53). One of the bushings is provided with a lip (54) which sealingly rests against the rod (6) when flushing medium is not supplied to the space between the set of rods and the set of tubes but allows passage of flushing medium at drilling.

Abstract: An interchangeable, sectional mining drill and bolt driver system for use with a drilling machine, includes a chuck, a driver, a bolt wrench-drill steel driver, a combination driver, a male hex coupler, a female hex coupler, a universal bar, a flat spring-double dimple clip, and a drill bit. The system can be converted from a vacuum debris removal system to a water debris flushing system by connecting a main water valve to a water system base and inserting a first water valve, a second water valve, and a finishing water insert into respective sections of the mining drill system.

Abstract: A reverse circulation deep hole rock bit that includes a drill bit connector tube telescopically extended into a drill bit housing to cooperatively form a part of a radial inner fluid channel for cuttings to flow axially outwardly and a radial outer annular clearnace space, a plurality of angularly spaced pressurized fluid passage that open to the annular space and a check valve in each fluid fluid passage to permit inward flow of fluid, but to block fluid flow in the opposite direction. A plurality of angularly spaced cutter arms have arcuate tubular segments secured to axial and radial outer portions of the arms while a radially inner tubular skirt is secured to or abuts against the axial outer portions of the arms.

Abstract: A pressure actuated hydraulic seal ring is disclosed for sealing to a rotating cylindrical member. The seal ring clears the rotating member when no hydraulic fluid is applied to its outer diameter. When hydraulic pressure is introduced to its outer diameter, a net compressive force is applied to the seal ring causing it to collapse in radially. The rotating cylindrical member includes a port through an external cylindrical surface which communicates with a conduit in the wall of the cylindrical member. The seal ring includes two inner sealing surfaces which straddle the port in the cylindrical surface where the ring is non-rotatingly supported by a ring retainer disposed about the exterior of the cylindrical surface. A passage extends from the outer diameter of the seal ring to a channel between the two inner sealing surfaces.

Abstract: A boring head for duo-pipe drilling apparatus comprises a body having a passage for material return extending therethrough from the cutting end to the coupling end, the passage having an inlet at the cutting end displaced from the axis of rotation of the head and extending substantially across the full radius thereof, and an exit at the coupling end co-axial with the axis of rotation. The cutting end comprises one or more teeth having attacking edges overlying the inlet and beveled for mechanically displacing material into the inlet upon rotation of the head. Fluid supply galleries open into the passage for directing pressurized fluid from the duo-pipe system towards the exit of the passage for flushing cut material to the exit. The coupling end of the boring head is adapted for connection to the duo-pipe system with the annular passage of the duo-pipe system in communication with the fluid supply galleries and with the inner tube of the duo-pipe system in communication with the exit of the passage.

Abstract: The invention comprises an elongated housing having a valve body reciprocal therein between predetermined limits of oscillation and the valve body includes a spherical valve member automatically shiftable between open and closed positions as the valve body is shifted between its limit positions. A tubular plug is provided and may be used to lock the tubular valve member in the open position and the valve body is yieldingly urged to the limit position in which the valve member is in the closed position. The valve body, however, is constructed in a manner whereby fluid flow through the housing in a first direction above a predetermined velocity will maintain the valve body in the other limit position with the valve member in its open position.

Abstract: A backflow control system for use in a gas circulation roller cone rock bit is disclosed wherein a single unit combination liquid-separator and positive action poppet check valve is used to restrict the entrance of water into roller cone bearings during drilling and to restrict the ingestion of detritus into the bearings and into the bit chamber during drilling interruptions. A quick-change mounting permits easy transfer of the valve unit form bit to bit.

Abstract: A kelly valving apparatus for controlling flow of fluid through a kelly and drill string comprises a rotatable tubular section having a fluid conveying bore adapted to be attached to the drill string at the kelly with a valve associated valve body valving the flow of fluids through the bore. A remotely operable operator is rotatable with the rotatable tubular section, operably engaging the valve for moving the valve between positions which open and close the bore, the operator including at least one hydraulic cylinder having an extensible ram actuated by hydraulic fluid, and linkage is connected to the valve and the hydraulic cylinder so that extension/contraction of the ram effects an opening or closure of the bore. A liquid interface fluid collector ring is positioned adjacent the rotatable tubular section for transmitting pressurized hydraulic fluid to the hydraulic cylinder, even during spinning of the cylinder with the tubular section.

Abstract: A side pocket mandrel for use in gas lift wells and having a sleeve valve in its side pocket receptacle for closing the receptacle's lateral ports when no flow control device is disposed therein. The sleeve valve is latched in its port-closing position but is readily displaced to its open position when a gas lift valve or other flow control device is installed in the receptacle. When the flow control device is withdrawn from the receptacle, the sleeve valve is returned to its closed position, there being provision for automatically coupling the sleeve valve and flow control device together in end-to-end relation in response to the flow control device being installed in the receptacle and for automatically uncoupling them in response to removal of the flow control device from the receptacle. The seals carried by the flow control device seal in the same bore in which the seals of the sleeve valve engage and are, therefore, equal in diameter.

Abstract: An inside blowout preventer including a valve seat pocket and a replaceable valve seat, the valve seat having a lip to bear the longitudinal back pressure in the presence of blowout type pressures from below without causing outward pressure of the pocket seat which cause distortions of the pin end in which the pocket is located.

Abstract: A retrievable float valve hanger tool assembly provides a hanger sub having a first upper connection for attaching the hanger sub, for example, threadably, to a drill string or work string. A second lower connection means on the sub provides both external and internal threaded (for example) connections, which allow the sub to be connected on its inner threads to a float valve canister and at its external threads to an extension which forms a protective housing about the float valve and its valve canister during operation. The device places the float valve below the joint of the sub and the extension so that an explosive charge can be detonated at the joint allowing easy removal of the float valve from the drill string in the event that the drill pipe becomes stuck. A continuous bore through the assembly allows fluid circulation through the tool in the work string and also allows the explosive charge to be lowered by wireline, for example, to the tool assembly at the appropriate joint.

Abstract: A multi position safety valve retainable within an internal portion of a drill string casing (s) and responsive to the greater differential pressure in an internal fluid passage to displace a valve head (32) relative to a valve seat (VS) from its normal partially open position to either a wide open or a closed position. The valve head (32) is attached to a valve stem (30) that extends through a valve chamber and slideably mounted in opposite closed ends of a valve body and returnable to and maintained in the partially open position by opposing compression springs (34) (36) situated between opposite ends (22) of the valve body (VB) and one side of an intermediate abutment (30c) of the valve stem (30) and an intervening disc (38) on the opposite side thereof. The disc 38 is moveable into and out of seating engagement with an intermediate stop (20a) by one spring (34) and the intermediate abutment (30c) of the valve stem respectively.

Abstract: A method for protecting a well formation during gravel packing in which a back pressure valve is held off of its seat while gravel is being placed in the well, is automatically closed as the wash pipe is removed from the screen and in which the valve is returned to open position by a force exerted from above, either hydraulic or mechanical.A valve is held open by a prop-out which is removable to permit the valve to swing to closed position and thereafter the valve is again opened in response to mechanical or hydraulic force from above.

Abstract: A method for protecting a well formation during gravel packing in which a back pressure valve is held off of its seat while gravel is being placed in the well, is automatically closed as the wash pipe is removed from the screen and in which the valve is returned to open position by a force exerted from above, either hydraulic or mechanical.A valve is held open by a prop-out which is removable to permit the valve to swing to closed position and thereafter the valve is again opened in response to mechanical or hydraulic force from above.

Abstract: A valve-nozzle assembly is disclosed for use in a rock-drilling bit, which assembly utilizes a backflow valve with a replaceable nozzle insert.

Abstract: An improved kelly valve of a type wherein a flexible inner valve body closes the valve passageway responsive to the pressure of a gaseous control fluid contained within a sealed chamber and opens the passageway responsive to exterior pressure of drilling fluid or of tools being passed through the valve. The improvements enhance the operating life of the flexible member and simplify the valve structure and assembly and disassembly procedures.

Abstract: A device for preventing unwanted objects from entering the ball assembly of a float collar or float shoe and otherwise damaging or plugging the valve mechanism therein is disclosed. The device comprises a screen constructed of expanded metal and rigidly affixed to the interior of the float collar or float shoe above the ball valve assembly. The screen portion is either mounted to the interior surface of the float collar sleeve by an annular structural member or mounted to a structural band which is partially embedded in the concrete portion of the float collar or casing guide shoe.

Abstract: Methods and apparatus for controlling fluid flow wherein, according to the methods, a pressure-actuated main valve is conditioned to operate by fluid pressure actuation of a pilot valve, which closes a fluid flow passage through the main valve so that the main valve may then be actuated by fluid pressure. The apparatus is a self-piloting check valve apparatus, disclosed in three embodiments, wherein dual valves are provided. One of the valves serves as a pilot valve and is shown in the form of a spring-biased check valve, closing of which permits closing of a main ball valve adapted to withstand highly elevated pressures. The sealing elements of the valve are fully protected during flow periods whereby fluid erosion is prevented. Full opening flow passages are provided through the valves in each embodiment of the apparatus.

Abstract: A check valve for a rock drill comprises a valve plate carrying a cylindrical strainer. An insert is carried by the valve plate and is movable between valve-open and valve-closed positions. A spring biases the insert to a valve-closed position. The insert unit includes a lid which engages and covers the top of the strainer in a valve-open position, and a bottom plate which covers the valve plate in a valve-closed position to prevent cuttings from fouling the valve mechanism.

Abstract: A combination drilling and belling apparatus includes a frame having at one end a drilling area for drilling a borehole in the earth. A pair of belling arms are pivotally carried by the frame and are selectively movable between a drilling position and a non-drilling position. The belling arms have a drilling surface such that when the belling arms are moved to the drilling position and the apparatus is rotated, the belling arms same form an enlarged bell-shaped cavity. When the belling arms are in a non-drilling position, a valve means is provided for closing an opening through a side wall of a drilling mud flow conduit, thereby preventing flow of drilling mud through the opening. When the belling arms are in the drilling position, the valve means is moved to an open position whereby drilling mud can flow from the cavity through the opening and upwardly through the conduit, carrying the cuttings therewith.

Abstract: A rotary rock bit with passageways for conducting air or other gaseous fluid to cool the bearings and flush cuttings from the borehole includes valve means for controlling the entry of water into the bearings. The stream of air or other gaseous fluid is directed through a valve system that prevents water from reaching the bearings. In one embodiment a truly positive backflow shutoff valving arrangement through both the nozzle and bearing passageways provides a means for more effectively preventing water and cuttings from entering the bearings and bearing passageways of the bit.

Abstract: A check valve assembly for permitting unrestricted flow in one direction and limited flow in the reverse direction comprising: a valve body having a longitudinal flowbore therethrough; a seat member carried by the valve body; a closure member carried by the valve body for movement from a normally open position, in which flow through the flowbore is unrestricted, to a closed position engaging the seat member, in which reverse flow through the valve body is prevented; and a reciprocal sleeve member carried by the valve body for movement between a first position, preventing movement of the closure member to its closed position, to a second position, allowing movement of the closure member to its closed position.

Abstract: A well drilling tool including a tubular member having a bore therethrough and adapted for connection in a drilling string to form a flow passage for drilling fluid and a full opening rotatable ball type bore closure means pivotally mounted with the tubular member in the bore of the tubular member for enabling desired flow down the bore of the drill string and which automatically rotates closed when incipient well pressure conditions indicate the direction of flow in the bore may be reversed. The drilling tool includes a means for releasably locking the ball in the open position in response to a predetermined directional pressure in the bore to render inoperative the automatic operation of the ball. The drilling tool may be employed by stabbing the tool in a drilling string having an upwardly flow in the bore of the drilling string to connect the tool with the drilling string for subsequently blocking the upwardly flow.