Abstract: An artificial lift system for a well having a wellhead reciprocates a rod string with an uphole pump unit at the wellhead to operate a downhole pump unit in the well and lift fluid in the well. A rod segment coupled to the rod string at the wellhead has first opposing surfaces facing in first opposing directions. Opposing catchers are movable laterally relative to the rod segment at the wellhead. Each of the catchers has a face with second opposing surfaces facing in second opposing directions opposite to the first opposing directions. The catchers moved in a first condition have the second opposing surfaces disengaged from the first opposing surfaces of the rod segment, but the catchers moved in a second condition have the second opposing surfaces engaged with the segment's first opposing surfaces to hold the rod string in place.

Abstract: A long-stroke pumping unit includes: a tower; a counterweight assembly movable along the tower; a drum connected to an upper end of the tower and rotatable relative thereto; a belt having a first end connected to the counterweight assembly, extending over the drum, and having a second end connectable to a rod string; a prime mover for reciprocating the counterweight assembly along the tower; a sensor for detecting sudden acceleration of the counterweight assembly due to failure of the rod string; at least one of: a braking system for halting free-fall of the counterweight assembly; and an arrestor system for absorbing kinetic energy of the falling counterweight assembly; and a controller in communication with the sensor and operable to activate the braking or arrestor system in response to detection of the sudden acceleration.

Abstract: A sliding sleeve has a sensor that detects plugs (darts, balls, etc.) passing through the sleeves. A first insert on the sleeve can be hydraulically activated by the fluid pressure in the surrounding annulus once a preset number of plugs have passed through the sleeve. Movement of this first insert activates a catch on a second insert. Once the next plug is deployed, the catch engages it so that fluid pressure applied against the seated plug through the tubing string can moves the second insert. Once moved, the insert reveals port in the housing communicating the sleeve's bore with the surrounding annulus so an adjacent wellbore interval can be stimulated. The first insert may also be hydraulically activated after a preset time after a plug has passed through the sleeve. Several sleeves can be used together in various arrangements to treat multiple intervals of a wellbore.

Abstract: A flow tool has a sensor that detects plugs (darts, balls, etc.) passing through the tool. An actuator moves an insert in the tool once a preset number of plugs have passed through the tool. Movement of this insert reveals a catch on a sleeve in the tool. Once the next plug is deployed, the catch engages the plug on the sleeve so that fluid pressure applied against the seated plug through the tubing string can move the sleeve. Once moved, the sleeve reveals ports in the tool communicating the tool's bore with the surrounding annulus so an adjacent wellbore interval can be stimulated. The actuator can use a sensor detecting passage of the plugs through the tool. A spring disposed in the tool can flex near the sensor when a plug passes through the tool, and a counter can count the number of plugs that have passed.

Abstract: A sliding sleeve has a sensor that detects plugs (darts, balls, etc.) passing through the sleeves. A first insert on the sleeve can be hydraulically activated by the fluid pressure in the surrounding annulus once a preset number of plugs have passed through the sleeve. Movement of this first insert activates a catch on a second insert. Once the next plug is deployed, the catch engages it so that fluid pressure applied against the seated plug through the tubing string can moves the second insert. Once moved, the insert reveals port in the housing communicating the sleeve's bore with the surrounding annulus so an adjacent wellbore interval can be stimulated. The first insert may also be hydraulically activated after a preset time after a plug has passed through the sleeve. Several sleeves can be used together in various arrangements to treat multiple intervals of a wellbore.

Abstract: A flow tool has a sensor that detects plugs (darts, balls, etc.) passing through the tool. An actuator moves an insert in the tool once a preset number of plugs have passed through the tool. Movement of this insert reveals a catch on a sleeve in the tool. Once the next plug is deployed, the catch engages the plug on the sleeve so that fluid pressure applied against the seated plug through the tubing string can move the sleeve. Once moved, the sleeve reveals ports in the tool communicating the tool's bore with the surrounding annulus so an adjacent wellbore interval can be stimulated. The actuator can use a sensor detecting passage of the plugs through the tool. A spring disposed in the tool can flex near the sensor when a plug passes through the tool, and a counter can count the number of plugs that have passed.

Abstract: The present invention relates to a control system for selectively supplying electrical power in a remote environment. The system comprises a plurality of electrical circuits, each designed to operate over a unique frequency passband. Power transmitted within the frequency passband of a circuit is filtered through that circuit to power a corresponding remote device. One or more remote devices can be simultaneously powered by transmitting power within the frequency passbands of the corresponding circuits. It is advantageous to design relatively narrow passbands to accommodate a relatively large number of circuits and corresponding devices for remote operation and a triac, rectifier or other suitable turn-on gate can be incorporated into each circuit to effectively control the width of the frequency passband of each circuit. Alternatively, an operational amplifier could be used.

Abstract: Methods and apparatus for detecting an operation of a downhole tool using an optical sensing system are disclosed. In an embodiment, a flow control device has an inner tubular member moveable relative to an outer tubular member and a thermally responsive chamber capable of a change in temperature during a movement between the inner tubular member and the outer tubular member. Detecting the change in temperature in the thermally responsive chamber with an optical sensing system provides real time knowledge of the position of the flow control device. In another embodiment, a flow control device comprises an inner tubular member moveable relative to an outer tubular member that produces an acoustic signal during a movement between the inner tubular member and the outer tubular member. Detecting the acoustic signal with an optical sensor provides real time knowledge of the position of the flow control device.

Abstract: The present invention relates to a control system for selectively supplying electrical power in a remote environment. The system comprises a plurality of electrical circuits, each designed to operate over a unique frequency passband. Power transmitted within the frequency passband of a circuit is filtered through that circuit to power a corresponding remote device. One or more remote devices can be simultaneously powered by transmitting power within the frequency passbands of the corresponding circuits. It is advantageous to design relatively narrow passbands to accommodate a relatively large number of circuits and corresponding devices for remote operation and a triac, rectifier or other suitable turn-on gate can be incorporated into each circuit to effectively control the width of the frequency passband of each circuit. Alternatively, an operational amplifier could be used.

Abstract: Electrical power generators and methods of producing power in a subterranean well are provided. In a described embodiment, fluid flow through a fluid conduit causes a member to displace or vibrate. The displacement of the member is utilized to induce strain in a piezoelectric material, thereby causing the piezoelectric material to produce electricity. Various means may be used to create turbulence in the fluid flow, thereby increasing displacement of the member, resulting in increased power output from the generator.

Abstract: Methods and apparatus for detecting an operation of a downhole tool using an optical sensing system are disclosed. In an embodiment, a flow control device has an inner tubular member moveable relative to an outer tubular member and a thermally responsive chamber capable of a change in temperature during a movement between the inner tubular member and the outer tubular member. Detecting the change in temperature in the thermally responsive chamber with an optical sensing system provides real time knowledge of the position of the flow control device. In another embodiment, a flow control device comprises an inner tubular member moveable relative to an outer tubular member that produces an acoustic signal during a movement between the inner tubular member and the outer tubular member. Detecting the acoustic signal with an optical sensor provides real time knowledge of the position of the flow control device.

Abstract: Method and apparatus are presented for perforating a subterranean formation so as to establish fluid communication between the formation and a wellbore, the wellbore having casing cemented therein, the casing having a cement sheath therearound. The casing is perforated with a mechanical perforator and thereafter a propellant material is ignited within the casing thereby perforating the cement sheath. The formation may thereafter be stimulated with an acid stimulator. The mechanical perforator may include use of a toothed wheel, or a needle-punch perforator. The propellant may be deployed in a sleeve and may comprise an abrasive material.

Abstract: There is a need to better understand well conditions during gravel pack completions and during production through a gravel pack. The sensors that are used to determine the conditions at the actual interface between the gravel pack and the production interval are located directly on the gravel pack assembly. This allows for the most accurate and timely understanding of the interface conditions. Sensors along the length of the gravel pack can provide real time bottom hole pressure and temperature readings. Other sensors could provide information on flow rate of fluids produced as well as density measurements. Thus, during completion, the sensors can provide information on the effectiveness of gravel placement. During production, the sensors could provide instantaneous information on dangerous well conditions in time to minimize damage to the well equipment.

Abstract: The present invention relates to a control system for selectively supplying electrical power in a remote environment. The system comprises a plurality of electrical circuits, each designed to operate over a unique frequency passband. Power transmitted within the frequency passband of a circuit is filtered through that circuit to power a corresponding remote device. One or more remote devices can be simultaneously powered by transmitting power within the frequency passbands of the corresponding circuits. It is advantageous to design relatively narrow passbands to accommodate a relatively large number of circuits and corresponding devices for remote operation and a triac, rectifier or other suitable turn-on gate can be incorporated into each circuit to effectively control the width of the frequency passband of each circuit. Alternatively, an operational amplifier could be used.

Abstract: A process and apparatus for treating a wellbore, comprising subjecting a substantially same portion of the wellbore to vibratory waves produced by a plurality of vibratory wave generators. The vibratory waves may have about the same frequency or a plurality of frequencies, and the frequencies may partially overlap, not overlap, or be modulated across a range. Additionally, the frequencies may be modulated in an oval, hoop, and flexural modes. The vibratory waves may be produced by firing the vibratory wave generators simultaneously or in sequence. Combinations of a vibrating pipe, piston pulser, or valve may be used as vibratory wave generators. In a preferred embodiment, the thickness and change of thickness of a mudcake on the interior surface of a wellbore are measured to evaluate the effectiveness of the wellbore treatment.

Abstract: Method and apparatus are presented for perforating a subterranean formation so as to establish fluid communication between the formation and a wellbore, the wellbore having casing cemented therein, the casing having a cement sheath therearound. The casing is perforated with a mechanical perforator and thereafter a propellant material is ignited within the casing thereby perforating the cement sheath. The formation may thereafter be stimulated with an acid stimulator. The mechanical perforator may include use of a toothed wheel, or a needle-punch perforator. The propellant may be deployed in a sleeve and may comprise an abrasive material.

Abstract: A system of downhole communication and control is provided in methods and associated apparatus for data retrieval, monitoring and tool actuation. In a described embodiment, an item of equipment installed in a tubular string has a first communication device associated therewith. A tool conveyed into the tubular string has a second communication device therein. Communication is established between the first and second devices. Such communication may be utilized to control operation of the tool, retrieve status information regarding the item of equipment, supply power to the first device and/or identify the item of equipment to the tool.

Abstract: There is a need to better understand well conditions during gravel pack completions and during production through a gravel pack. The sensors that are used to determine the conditions at the actual interface between the gravel pack and the production interval are located directly on the gravel pack assembly. This allows for the most accurate and timely understanding of the interface conditions. Sensors along the length of the gravel pack can provide real time bottom hole pressure and temperature readings. Other sensors could provide information on flow rate of fluids produced as well as density measurements. Thus, during completion, the sensors can provide information on the effectiveness of gravel placement. During production, the sensors could provide instantaneous information on dangerous well conditions in time to minimize damage to the well equipment.

Abstract: Sensors are attached directly to portions of the sand screen of a gravel packing assembly, with connectors to the sensors run through elements of the screen that are hollow for that purpose. The hollow element can be the trapezoidal wire that is circumferentially wrapped to form the outer screen or one of the outer spacers used to provide a stand-off of the wire from the underlying tubing. Sensors can detect such conditions as pressure, temperature, flow rate, density, etc., and can provide real-time information on the effectiveness of gravel placement during packing and on well conditions during production.

Abstract: Method and apparatus are presented for perforating a subterranean formation so as to establish fluid communication between the formation and a wellbore, the wellbore having casing cemented therein, the casing having a cement sheath therearound. The casing is perforated with a mechanical perforator and thereafter a propellant material is ignited within the casing thereby perforating the cement sheath. The formation may thereafter be stimulated with an acid stimulator. The mechanical perforator may include use of a toothed wheel, or a needle-punch perforator. The propellant may be deployed in a sleeve and may comprise an abrasive material.