Abstract: A closure mechanism for preventing fluid access to an inner tube of a core barrel assembly is disclosed in which the closure mechanism is configured to move from an open, or unoccluded, condition to an occluded condition in response to increased fluid flow rates and pressure differentials occurring at the closure mechanism. The closure mechanism is also configured to maintain occlusion of the inner tube under substantially all types of drilling conditions, and particularly those where conventional closure mechanisms may fail, such as in horizontal drilling. The closure mechanism generally includes a conduit structure associated with the inner tube, and having a seat, an occlusion structure, such as a ball, and releasing structure which maintains the occlusion structure in spaced relationship to the seat until increasing pressure differentials result in release of the occlusion structure to register with the seat.

Abstract: The present invention is a sidewall coring assembly and method for taking a core sample at an angle to an existing borehole. The assembly includes a core barrel run at the end of a drill string and having a whipstock suspended below it, the whipstock having an anchor packer at its lower end. The packer is hydraulically inflated through the core barrel and an hydraulic line extending from the bottom thereof, the core barrel is released from the whipstock and the hydraulic line, and lowered to core at the angle and azimuth dictated by the whipstock. After coring is completed, the core barrel is withdrawn from the well and subsequently the whipstock and packer are retrieved with a stinger run on the drill string.

Abstract: The application is directed to a shoe assembly with a core catcher for retaining a core of an unconsolidated rock or earth formation in a coring barrel. The shoe assembly includes a tube section adapted to fit removably within the core barrel near the coring bit. Two sets of hinged fingers are attached to the inner surface of the tube section on respective circumferential lines which are displaced from each other. The fingers are movable about the hinged ends between an open position in which the fingers do not significantly occlude the passageway, and a closed position in which the fingers do occlude the passageway. The fingers are biased toward the closed position by means of respective springs associated with each finger. When in the closed position, the two sets of fingers together occlude at least 90% of the cross-section of the passageway. The fingers are urged to the open position by the action of a core moving through the coring barrel away from the drilling end.

Abstract: A stabilizer bearing assembly is described for maintaining separation between a substantially nonrotating inner tube assembly and a rotating core barrel within which the inner tube assembly is disposed. The bearing assembly comprises a cylindrical tube having a cylindrical sleeve segment concentrically slidably mounted on the tube over an external bearing portion thereof. The tube includes an upper and a lower segment, with the hardened bearing portion over which the sleeve sits being located near the lower end of the upper segment. A flange demarcs the upper edge of the bearing portion. The upper end of the lower tube segment is threadedly attached over the lower end of the upper segment. The sleeve segment is trapped between the flange and the edge of the upper end of the lower tube segment. The inner surface of the sleeve has a plurality of spaced longitudinal furrows and the outer surface of the sleeve has raised ridges corresponding to the furrows.

Abstract: A nozzle retention system for a drill bit which includes a nozzle member which is retained by means of a keyway in the bit body. The bit body can include a partially cylindrical bore, truncated by opposing walls to form a lower contact surface within the bit body. The nozzle will be conformed to pass through the bore in a first orientation, and to be retained in the bore and against such contact surface when the nozzle is rotated to the second orientation.

Abstract: Jamming caused by absorbent members in sponge core barrels or loss of coring information caused by oil wipes in oil field boreholes in which sponge core coring tools are disposed can be avoided by employing a method and tool wherein the absorbent member is formed in placed in contact about the core after the has been cut and disposed within the inner tube. In the illustrated embodiment, a liquid foam is catalytically formed from two constituent parts. The constituent parts are hydraulically forced from longitudinal chambers defined within the inner tube walls into an area in the throat of the bit where the parts meet and exothermically generate a liquid foam. The liquid foam rises into a plurality of longitudinal open chambers defined within the inner tube. Each of the open chambers has a longitudinal slot defined therethrough which communicates the chamber with the axial bore in which the core is disposed.

Abstract: An axial bore is defined throughout the hydraulic lift inner barrel. This axial bore is communicated with the interior of the inner tube thereby allowing the interior of the inner tube to be flushed prior to initiation of the coring operation. When the coring operation is begun, flow of drilling fluid to the interior of the inner tube is prevented by allowing a ball dropped within the drill string to seat within a plug through which the communicating axial bore is defined. Once the flow of drilling fluid to the interior of the inner tube is stopped, the coring operation can begin. After the coring operation is completed, a second ball is dropped and allowed to seat within an inner mandrel through which the axial bore of the coring tool is also defined. Once the axial bore of the inner mandrel is closed, drilling fluid is forced into an expansion chamber within a telescopic piston disposed circumferentially outside of the inner mandrel. The piston is connected to the inner tube.

Abstract: A positively driven full closure core catcher for use with soft or unconsolidated cores is comprised of an inner tube shoe into which a plurality of windows have been cut. In each window is a corresponding one of a plurality of flapper valves. The flapper valves are spring-biased to a withdrawn position outside of the interior of the inner tube shoe. A cam member is in sliding contact with an inclined rear surface of the flapper valve. Longitudinal displacement of the cam member with respect to the inclined surface of the flapper valve causes the cam to ride down the inclined surface of the valve thereby forcing the rotatable flapper valve into the interior of the inner tube shoe and into a fully closed position. The cam member is substantially radially fixed and is selectively disengaged from the inner tube shoe to which it is temporarily coupled by a collet assembly. The collet assembly is coupled to a cylinder on which the cam is fixed.

Abstract: A core spring type core catcher and a full closure core catcher are completely concealed from the core within a coring tool. The full closure catcher is reliably actuated to assume a closed configuration without dependence upon gravity or an interference diametrical fit with the core by use of a cam ring which is longitudinally displaced downwardly within the core barrel by a preloaded compression spring. The full closure core catcher is comprised of a plurality of flapper valves circumferentially disposed outside of the inner tube and concealed by the inner tube or a terminal extension of the inner tube. Disposed above the plurality of flapper valves, and also circumferentially disposed outside of and concentric with the inner tube is a cam ring. Similarly circumferentially disposed outside of and concentric with the inner tube is a preloaded coil compression spring bearing against the cam ring. The cam ring in turn is in sliding contact with a rear surface of each one of the plurality of flapper valves.

Abstract: A fragmented or unconsolidated core can be cut and retained within a coring tool without substantial disturbance of the core by the use of a shrouded core catcher. A core catcher is concentrically disposed within the coring tool and outside of a smooth, cylindrical sleeve telescopically disposed inside of the core catcher. The core catcher in turn is coupled to a lower assembly which can be selectively longitudinally fixed within the coring tool, but which is otherwise temporarily coupled to the sleeve. As the sleeve is longitudinally pulled upward after the completion of the coring operation, the lower assembly becomes longitudinally fixed within the coring tool and the sleeve, which heretofore has fully covered and concealed the core catcher, begins to be withdrawn from the core catcher, leaving it unconcealed. Ultimately, the core catcher is at least partially uncovered, thereby permitting activation and contact between the core catcher and the core disposed within the coring tool.

Abstract: Downward displacement of an inner tube with respect to the outer tube in a coring tool is effectuated by an apparatus comprising a bearing assembly, a cylinder, a piston telescopically disposed within the cylinder, and a mechanism for selectively applying an hydraulic force to the piston. The bearing assembly is longitudinally fixed with respect to the outer tube while providing rotational freedom with respect to the outer tube. A cylinder is axially disposed within the coring tool, is connected to the bearing assembly, and hence is rotationally free with respect to the outer tube. The piston, which is telescopically disposed within a cylinder, is downwardly longitudinally displaceable within the cylinder, and hence with respect to the outer tube. A mechanism is incorporated within the coring tool for selectively applying a hydraulic force to the piston in order to longitudinally displace the piston downwardly within the cylinder.

Abstract: A direct acting slug and wipe tool for use in drill pipe in drilling operations effects a cleaning operation by placing a rib inflated bladder in contact with the inside surface of a drill pipe in connection with a free floating pneumatic chamber. The inflatable bladder is toroidal and circumferentially disposed about and communicates with a sealed and closed chamber filled with a fixed amount or mass of gas. Weights may be added to the wiper in order to fix its equilibrium floating position. The wiper with the inflatable bladder is able to wipe the interior of the drill pipe even through those portions having a reduced inner diameter, such as at the drill pipe joints. Thus, as the drill pipe is tripped, the slug and wipe tool is longitudinally displaced with respect to the drill pipe through a plurality of drill pipe sections.

Abstract: An automatically operable hydraulic lift inner barrel is devised to lift the inner tube of the core barrel on a drill string. An inner mandrel is axially disposed within the outer tube of the coring tool. An outer piston which is selectively locked to the inner mandrel is telescopically and concentrically disposed about the inner mandrel. Fluid is selectively diverted from the outer tube into the inner mandrel and inside the outer piston. An inner locking piston within the inner mandrel responds to the hydraulic pressure to unlock the outer piston from the inner mandrel. The outer piston is then longitudinally displaced by the hydraulic pressure thereby lifting the inner tube which is connected to it. After the outer piston has moved a predetermined distance, the hydraulic pressure supplied to the inner mandrel and inside the outer piston reaches a second predetermined magnitude. Burst disks are then blown thereby relieving the hydraulic pressure within the outer piston inner mandrel.

Abstract: A mechanism for catching and holding a core within an inner tube in a drill string includes a slidable core catcher and a full closure core catcher. The slidable core catcher is disposed within the inner tube and is coupled to an inner tube ring concentrically mounted on the outside of the inner tube. The inner tube ring and the slidable core catcher are connected to each other by means of a shear pin slidable within a slot defined in the inner tube. An outer tube ring is connected to the outer tube concentrically disposed about the inner tube. When the outer tube ring contacts the inner tube ring as the inner tube is lifted, the inner tube ring is moved downwardly with respect to the inner tube, thereby pulling the core catcher with it. As the core catcher moves downwardly it is compressed by an inside conical surface provided near the end of the inner tube. This serves to effectuate operation of the slideable core catcher.