Abstract: A single phase sampling apparatus and method for retrieving a formation fluid sample at or above the bubble point of the sample. The apparatus utilizes a gas charge contained between a sample piston and a charging piston to maintain a formation sample at the desired pressure. The charging piston utilizes the hydrostatic pressure present at the depth of the desired formation sample to compress and therefore increase the gas charge to the appropriate pressure necessary to maintain the formation sample at the desired pressure. The utilization of hydrostatic pressure to increase the pressure of the gas charge allows the use of a low pressure gas charging system to prepare the apparatus prior to sampling, thereby increasing the safety and ease of use of the device.

Abstract: Integrated drilling and evaluation systems and methods for drilling, logging and testing wells are provided. The drilling and evaluation systems are basically comprised of a drill string, a drill bit carried on a lower end of the drill string for drilling a well bore, logging while drilling means included in the drill string for identifying subsurface zones or formations of interest, packer means carried on the drill string above the drill bit for sealing a zone or formation of interest below the packer means, a fluid testing means included in the drill string for controlling the flow of well fluid from the zone or formation of interest into the drill string, a function status monitor included in the drill string to evaluate the capacity of the various test instruments to function, and a function timer included in the drill string to automatically sequence the steps of various test procedures.

Abstract: Integrated drilling and evaluation systems and methods for drilling, logging and testing wells are provided. The drilling and evaluation systems are basically comprised of a drill string, a drill bit carried on a lower end of the drill string for drilling a well bore, logging while drilling means included in the drill string for identifying subsurface zones or formations of interest, packer means carried on the drill string above the drill bit for sealing a zone or formation of interest below the packer means, a fluid testing means included in the drill string for controlling the flow of well fluid from the zone or formation of interest into the drill string, a function status monitor included in the drill string to evaluate the capacity of the various test instruments to function, and a function timer included in the drill string to automatically sequence the steps of various test procedures.

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: 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 hydraulic control system for downhole tools enables convenient selection and actuation of a well tool assembly from among multiple well tool assemblies installed in a well. Each well tool assembly includes a control module having a selecting device and a fluid metering device. A predetermined range of pressure levels on one of multiple hydraulic lines causes the well tool assembly to be selected for actuation, a differential between pressure on that hydraulic line and pressure on another hydraulic line determines a manner of actuating the selected well tool assembly, and pressure fluctuations on one of the hydraulic lines causes fluid to be transferred from another hydraulic line to an actuator of the well tool assembly.

Abstract: An electrically insulating gap subassembly for inclusion in a pipe string (30) comprising a pair of tubular members (90, 98) having an electrically insulating isolation subassembly (94) threadably disposed therebetween is disclosed. The electrically insulating isolation subassembly (94) has an anodized aluminum surface that provides electrical isolation to interrupt electrical contact between the two tubular members (90, 98) such that electromagnetic waves (46, 54) carrying information may be generated thereacross.

Abstract: The present inventions contemplate improved annular flow safety valve apparatus and methods in which the valve comprises a bi-directional self-contained electromechanically operated valve assembly including a moveable seal, power source, electric motor, and control system, capable of operating with or without power or control inputs from the surface.

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: A test, drill and pull system for testing a well formation or zone of interest and further drilling of the well in a single trip into the wellbore. The system includes a surface readout tester valve, a rotation-operated reversing valve, a resettable packer, a packer lockout, a perforated anchor and a drill bit. In operation, the apparatus is run into the bottom of the well adjacent to the formation or zone of interest and the packer set and unset as desired. With the packer set, a surface readout tester valve probe is lowered into the apparatus on a wireline and latched into the tester valve so that multiple testing operations may be carried out if desired. After testing, the fluid recovery may be reversed out and analyzed by actuating the reversing valve by rotation of the tool string. Further, rotation engages the packer lockout such that when weight is picked upon the packer, the packer cannot be reset.

Abstract: A hydraulic control system for downhole tools enables convenient selection and actuation of a well tool assembly from among multiple well tool assemblies installed in a well. Each well tool assembly includes a control module having a selecting device and a fluid metering device. A predetermined range of pressure levels on one of multiple hydraulic lines causes the well tool assembly to be selected for actuation, a differential between pressure on that hydraulic line and pressure on another hydraulic line determines a manner of actuating the selected well tool assembly, and pressure fluctuations on one of the hydraulic lines causes fluid to be transferred from another hydraulic line to an actuator of the well tool assembly.

Abstract: Integrated drilling and evaluation systems and methods for drilling, logging and testing wells are provided. The drilling and evaluation systems are basically comprised of a drill string, a drill bit carried on a lower end of the drill string for drilling a well bore, logging while drilling means included in the drill string for identifying subsurface zones or formations of interest, packer means carried on the drill string above the drill bit for sealing a zone or formation of interest below the packer means, and a fluid testing means included in the drill string for controlling the flow of well fluid from the zone or formation of interest into the drill string. The drilling and evaluation systems and methods for using the systems allow one or more subsurface zones or formations of interest in a well to be drilled, logged and tested without the necessity of removing the drill string from the well.

Abstract: A downhole tool (100) for selectively providing fluid communication between the interior and the exterior of the tool (100). The tool (100) comprises a housing (102), a safety mandrel (130) slidably received within the housing (102) and an operating mandrel (114) slidably received within the housing (102). The safety mandrel (130) operates between a first position and a second position relative to the housing (102) in response to pressure being applied to the exterior of the housing (102). The operating mandrel (114) operates from a noncirculating position to a circulating position in response to pressure being applied to the interior of the housing (102) once the safety mandrel (130) has operated to its second position.

Abstract: A circulating valve and associated methods of servicing a well provide reliable operation, economical manufacture, and convenient maintenance in the circulating valve which is responsive to flow of fluid therethrough, and increased versatility in well servicing operations utilizing the valve. In a preferred embodiment, a circulating valve includes an upper case having a reverse circulating port formed radially therethrough, a circulating case having a circulating port formed radially therethrough, a lower adapter, a mandrel having a flow port formed radially therethrough, a biasing member, a ratchet, an inner sleeve, and a one-way flow restrictor carried on the mandrel. In an open configuration, fluid communication is permitted between the flow and circulating ports, and between the reverse circulating port and the flow restrictor. In a closed configuration, fluid communication is not permitted radially through the valve.

Abstract: An electrically insulating gap subassembly for inclusion in a pipe string (30) comprising a pair of tubular members (90, 98) having an electrically insulating isolation subassembly (94) threadably disposed therebetween is disclosed. The electrically insulating isolation subassembly (94) has an anodized aluminum surface that provides electrical isolation to interrupt electrical contact between the two tubular members (90, 98) such that electromagnetic waves (46, 54) carrying information may be generated thereacross.

Abstract: A subsea repeater apparatus (48) for communicating information between surface equipment (60) and downhole equipment (44) is disclosed. The apparatus (48) comprises an electromagnetic receiver (66, 68) that receives an electromagnetic signal (46) carrying information from downhole equipment (44) and an acoustic modem (54) that acoustically retransmits (56) the information to surface equipment (60) through the sea. The apparatus (48) may also comprise an acoustic modem (54) that receives an acoustic signal (64) carrying information from surface equipment (60) through the sea and an electromagnetic transmitter (50) that radiates electromagnetic waves (66) carrying the information into the earth.

Abstract: A downhole current generator generates power in a wellbore and includes a power section and an generator section. The power section has a sleeve slidably disposed within a housing which oscillates in response to the application of fluid pressure to the current generator. A piston is slidably attached to the sleeve and oscillates relative to the sleeve and the housing. The piston extends longitudinally into an generator section and has a plurality of magnets attached thereto which oscillate with the piston. Wire coil sections are fixed relative to the housing of the generator section and are positioned between the oscillating magnets such that a current is induced in the wire coil sections upon oscillation of the magnets.

Abstract: A downhole electromagnetic signal repeater (76) for communicating information between surface equipment and downhole equipment and a method for use of the repeater (76) is disclosed. The repeater (76) comprises a receiver (120) and a transmitter (124). The receiver (120) receives an electromagnetic input signal and transforms the electromagnetic input signal to an electrical signal that is inputted into an electronics package (122) that amplifies the electrical signal and forwards the electrical signal to the transmitter (124) that transforms the electrical signal to an electromagnetic output signal that is radiated into the earth.

Abstract: A downhole tool (34) comprising a housing (60), a mandrel (76) slidably disposed within the housing (60), the mandrel (76) having a fluid passageway (52) extending axially therethrough, a valve (50) disposed within the mandrel (76), the valve (50) having first and second positions to selectively permit and prevent fluid flow through the fluid passageway (52) of the mandrel (76) and first and second pistons (98, 104) slidably disposed between the housing (60) and the mandrel (76), the first and second pistons (98, 104) slidably displacable in opposite directions relative to the housing (60) in response to a differential fluid pressure, the first and second pistons (98, 104) selectively engagable with the mandrel (76) to respectively displace the mandrel (76) in first and second directions, thereby operating the valve (50) between said first and second positions.

Abstract: Method and apparatus for testing and sampling open-hole oil and gas wells. The apparatus includes a packer, a surge chamber, a closure valve which may be opened to flow fluid into the surge chamber, and a sampler. The surge chamber may be one of a pair of surge chambers, and the closure valve may be one of a pair of closure valves so that two surges may be carried out prior to obtaining a fluid sample in the sampler. In operation, the packer is placed in a set position by setting down weight. The closure valves are also actuated when weight is set down. The first closure valve has a first predetermined time delay before opening so that the packer may be set, and the second closure valve has a second predetermined time delay so that the packer may be set and the first closure valve opened before a fluid sample is captured. By opening a vent tool at an upper end of the uppermost surge chamber, formation fluid may be forced back into the formation or zone of interest by a bull-heading operation.