Abstract: A downhole valve for use within a string of tools in a well for controlling a hydraulic activation circuit. The valve has a housing with an inlet and an outlet, defining a portion of the circuit extending between the inlet and the outlet. A moveable piston within the housing in a first position provides communication between uphole and downhole parts of the circuit, and in a second position isolates the uphole and downhole parts of the circuit. A frangible member is constructed to support, in an intact condition, the piston in one of these two positions against a biasing force, and in a shattered condition enables the piston to move in response to the biasing force to the other position. A detonating member extending through the frangible member propagates a detonation wave to shatter the frangible member when desired, closing the valve.

Abstract: A well completion apparatus disposed in a wellbore having first and second tubings and a tool disposed in the second tubing. An inductive coupler has a male coil located in the first tubing and is configured to receive an input signal. A female coil in the inductive coupler is attached to the first tubing and is electrically connected to the tool for inductively coupling to the male coil. An output signal is induced in the female in response to the input signal received in the male coil, and the output signal is provided to activate the tool in response to the input signal.

Abstract: A tool for performing a downhole function in a horizontal or highly deviated well has a downhole structure with a longitudinal axis and constructed to turn about the axis in response to a moment applied about the axis. The structure includes at least one ballast chamber containing a flowable inert ballast material, such that the gravitational center of the material-containing chamber is effectively offset from the longitudinal axis of the structure to enable the chamber to contribute to gravitational orientation of the tool within the well to a desired position. In another configuration, the structure is rotatable within a housing and supported by bearings. The chamber is preferably filled with tungsten or depleted uranium powder for maximum density. A swivel for use with the tool, capable of passing both hydraulic pressure and detonation waves, decreases the overall length of the rotating part of the tool string.

Abstract: Apparatus and method for activating a device in a well, such as firing a perforating gun in a well. An electrically-activated firing system is coupled to an actuating assembly, which includes a release piston movable by fluid pressure, a firing pin, and a frangible element connected to hold the release piston in place, the frangible element being shattered in response to electrical activation of the firing system. A locking mechanism locks the firing pin to prevent movement of the firing pin, and the release piston is connected to release the locking mechanism if a minimum amount of fluid pressure is applied to the release piston after electrical activation of the firing system. A detonating assembly is connected to the perforating gun and is activable by the firing pin. The detonating assembly is activated when the firing pin is released by the locking mechanism to impact the detonating assembly.

Abstract: An apparatus for sequentially performing multiple downhole functions in a well has tubing arranged to transmit pressure conditions from the surface of the well, upper and lower hydraulically activated firing heads suspended within the well on the lower end of the tubing, and a hydraulically responsive movable member between the tubing and the firing heads. Each firing head is configured to detonate an associated tool in response to an associated elevated tubing pressure condition. The movable member transmits a first elevated pressure condition to activate one of the firing heads, and moves in response to a subsequent elevated pressure condition to activate the other firing head. In one embodiment, the movable member has a through passage for transmitting the first elevated pressure condition, the passage being subsequently blocked by a ball dropped through the tubing to move the member in response to the second elevated tubing pressure condition.

Abstract: A downhole device and method for performing a function in a well. The device has a series of dedicated hydro-mechanical locks that prevent occurrence of an associated function. The hydro-mechanical locks are capable of being released directly by a respective elevated hydraulic activating pressure condition, and are constructed and arranged for sequential operation, such that a successive lock in the series cannot be released until after the hydraulic pressure condition required to release the preceding lock in the series has occurred. In a preferred embodiment, an actuator sequentially releases each lock in a series of locks, subsequently moving an operator to perform a function. A preferred implementation employs a series of resilient rings movable, sequentially, from a locking to an unlocking position, and a common actuator that effects these movements.

Abstract: A downhole valve is disclosed for use in a tubing-conveyed string of tools in a well bore, constructed to be actuated to open under pressure forces by dropping a drop bar from the well surface through the tubing. The valve, deployed in the well in a closed condition, has a frangible member arranged to be broken by the drop bar to enable the valve to open. The valve opens under well pressure forces when well pressure exceeds tubing pressure, and opens under tubing pressure forces when tubing pressure exceeds or substantially equals well pressure. The valve is particularly useful when opened in conjunction with the detonation of a perforating gun for overbalanced or underbalanced well perforation. Methods of operating a string of tools including the valve are also disclosed.

Abstract: A completions insertion and retrieval under pressure (CIRP) apparatus utilizes a snaplock connector to assemble uphole a tool string of any desired length prior to lowering the tool string into a wellbore for performing wellbore operations in the wellbore. The tool string could comprise a perforating gun string including a plurality of perforating guns interleaved with a corresponding plurality of snaplock connectors. The CIRP apparatus includes a winch housing connected to a lubricator, the lubricator being connected to a valve, the valve being connected to a connection apparatus, such as a deployment BOP or a snaplock operator, the connection apparatus being connected to a work string which extends into the wellbore.

Abstract: A new perforating method and release apparatus enables a wellbore operator to perforate long length intervals of a wellbore during a single perforating run into the wellbore, the interval of the wellbore being perforated being longer in length than the length of a wellhead lubricator. The new perforating method includes the step of suspending a perforating gun suing from a conveyor in a wellbore. The gun string includes a detonating cord and a novel automatic release apparatus interconnected between a first part of the gun string and a second part of the gun suing which includes a perforating gun. The automatic release apparatus includes a frangible member which will shatter in response to a detonation wave propagating in the detonating cord thereby initiating the release of the second part of the gun swing from the first part of the gun suing. The initiation of such release takes place before the perforating gun detonates.

Abstract: A firing head adapted to connected between a coiled tubing and a perforating gun, is sized and shaped to enable it to move freely within a tubing string in the wellbore, may be actuated by fluid pressure within the coiled tubing, and includes a circulation and recirculation feature wherein wellbore fluid may be circulated through the firing head between the coiled tubing and an annulus around the tubing string, the circulation taking place either before or after detonation of the perforating gun. Three firing heads are discussed. One such firing head is a Circulation Direction Firing (CDF) Head. The CDF firing head circulates fluid from the wellbore to the coiled tubing and depresses a piston. Then, fluid pressure from the coiled tubing lifts the piston uncovering locking balls and propelling a firing pin to a booster of a detonating cord detonating the CDF firing head. Fluid circulation from the coiled tubing to the wellbore annulus begins after the CDF firing head detonates.

Abstract: A wellbore tool includes an anchor connected to a perforating gun, the anchor including an anchor slip disposed between upper and lower slip housings for expanding to grip a casing in the wellbore, a primary anchor release mechanism for unsetting the anchor slip and a secondary anchor release mechanism for unsetting the anchor slip when the primary anchor release mechanism is not activated. If the primary and secondary anchor release mechanisms have not been activated, the anchor slip can be set. The primary anchor release mechanism automatically unsets the anchor slip when a detonation wave, conducting in a detonating cord, propagates through an interior space of a frangible member, the detonation wave shattering the frangible member and detonating the perforating gun. When the frangible member is shattered, the anchor slip can then be unset thereby allowing the perforating gun to fall to a bottom of the wellbore.

Abstract: A shock absorber, adapted to be disposed above a perforating gun in a tool string and adapted to be disposed in a wellbore, includes a crushable element disposed between an inner and outer housing, a frangible breakup element, and a detonating cord disposed within the frangible breakup element and connected to the perforating gun. In operation, a detonation wave propagates within the detonating cord on its way toward the perforating gun. However, before the detonation wave reaches the perforating gun, the detonation wave propagates through the frangible breakup element. In response to the passage of the detonation wave through the frangible breakup element, the frangible element shatters into a multitude of pieces. Before the frangible element shatters, the frangible element absolutely prevents any shock from being absorbed by the shock absorber of the present invention. As a result, preloading effects are avoided.

Abstract: A production valve includes an outer housing having a production port, a piston disposed within the outer housing and adapted to move from one position to another position, a frangible breakup element supporting the piston in the one position, and a detonating cord adapted for propagating a detonation wave passing through the center of the piston and the breakup element. The detonation wave shatters the frangible breakup element when the detonation wave, propagating within the detonating cord, passes through the breakup element. When the breakup element shatters, the support provided to the piston by the breakup element is removed. When the support provided to the piston by the breakup element is removed, the piston moves from the one position to the other position in response to either tubing pressure or rathole pressure or both, and the production port of the production valve opens when the piston moves to the other position.

Abstract: An automatic tubing release mechanism is adapted to be disposed in a wellbore between a tubing, on one end, and a perforating gun, on the other end. The release mechanism includes a frangible breakup tube, firing head positioned above the breakup tube, and the perforating gun positioned below the breakup tube when the release mechanism is disposed in the wellbore. A detonating cord is interconnected between the firing head and the perforating gun via the breakup tube. When the firing head detonates the perforating gun, the breakup tube shatters.

Abstract: A hydraulic safety pin is interconnected between a device, such as a pressure controlled firing head associated with a perforating gun, and a small diameter tubing in a wellbore. When, the small diameter tubing is filled with fluid under pressure, the hydraulic safety pin allows the fluid to fill the small diameter tubing but prevents the pressure of the fluid in the small diameter tubing from accidentally detonating the firing head when the pin is disposed in a first position; however, when the tubing is already filled with fluid under pressure, the hydraulic safety pin allows the pressure of the fluid in the small diameter tubing to detonate the firing head when the pin is disposed in a second position. The hydraulic safety pin may be installed in a special coupling, and multiple special couplings may be used in a tool string disposed in a wellbore.

Abstract: An explosive diode transfer system is interconnected between adjacent perforating guns of a modular perforating apparatus. The explosive diode transfer system includes a downwardly directed shaped charge, a booster, and a multi-density barrier interposed between the shaped charge and the booster. The multi-density barrier includes a first metal layer and a second metal layer spaced from the first metal layer thereby defining a sealed air-space between the first and second metal layers. The first metal layer, air space, second metal layer combination represents a plurality of different density barriers or layers which are collectively designed to prevent a first detonation wave, propagating from the booster to the shaped charge, from propagating therethrough, but nevertheless to allow a jet, propagating from the shaped charge to the booster, to propagate therethrough.

Abstract: A hydrostatic setting tool, adapted for setting an anchored device in a wellbore, includes a housing having a pair of ports exposed to well fluid at hydrostatic pressure. The ports lead to a shoulder of a setting mandrel. A barrier is disposed diametrically across the setting tool and an oil chamber is disposed between the setting mandrel and the barrier. The barrier includes an oil metering orifice disposed through a center thereof. A selectively operable apparatus, initially disposed in a closed position and blocking the oil metering orifice, is adapted to change from the closed position to an open position in response to a current delivered thereto from the well surface. An air chamber is disposed on the other side of the barrier. The well fluid places hydrostatic pressure on the shoulder of the setting mandrel thereby placing the same pressure on the oil in the oil chamber.

Abstract: In the representative embodiment of the method and apparatus of the invention which are disclosed herein, a well tool arranged for suspension in a well bore from a cable includes a mandrel that is telescopically arranged on the tool body and is operable after the tool is stationed in a well bore to be shifted upwardly and downwardly by the cable. A pressure-responsive actuator is arranged on the tool for being released in response to an initial downward movement of the suspension cable for rapidly extending an anchor on the tool body into engagement with the well casing. Thereafter, a successive upward movement of the suspension cable is effective for releasing the pressure-responsive actuator for slowly traveling to a position in the tool body where a firing pin on the body is released for detonating an impact-actuated explosive device on the tool only after a predetermined time delay following the upward cable movement.

Abstract: A well apparatus adapted to be disposed in a wellbore includes a perforating apparatus and a packer adapted to set and isolate an annulus above the packer from a rathole annulus below the packer, the perforating apparatus including a new and novel rathole differential pressure balanced firing system where the firing system includes a ball release sleeve holding a firing piston, means for initially opening a top end and a bottom end of the ball release sleeve to the rathole annulus below the packer; and a plurality of sequentially operable hydraulic systems, the top end of the ball release sleeve being initially open to the rathole annulus below the packer but being subsequently closed to the rathole annulus below the packer and then reopened to the annulus above the packer when the packer is set.

Abstract: A tension actuated device is adapted to be connected between a pipe string and an object stuck downhole in a wellbore and does not disconnect the pipe string from the object in response to a transient or temporary shock load that is temporarily applied to the pipe string. Rather, the tension actuated device selectively disconnects the pipe string from the object stuck downhole by continuously applying a pulling force of a predetermined magnitude to the device via the pipe string for a predetermined period of time.