A downhole tool, comprising one or more separate packers and sliding sleeves in the preferred embodiment, is actuable from a nonelectrical signal transmitted from the surface to the tool. The signal is received at the tool by a control system located within the tool. The control system operates in conjunction with a power supply in the tool to accomplish tool actuation. In the preferred embodiment, the valve member is temporarily retained in a sealing position, isolating pressure in one chamber from a different pressure in an adjacent chamber. The valve member or piston is temporarily retained by a high-strength fiber, such as Kevlar.RTM., in the preferred embodiment. The control system actuates the power source to heat a resistance heating wire, which causes failure in the fiber. Other mechanisms to trigger pressure-equalization can be used. The fiber can be cut by a cutter actuated electrically. The piston can be retained by solder which is melted electrically. The piston can be designed to be substantially in pressure balance so that the fiber can effectively hold the piston in place until it is rendered inoperative by heating up a resistance wire from the power supply as triggered by the control circuit. Once the fiber fails, the piston is released and the pressure is equalized. The pressure-equalization can be used to shift a setting sleeve to set a packer or to open or close a sliding sleeve valve. Different valves can be actuated in series, using different control signals, or in parallel, using one control signal. In the alternative, the same valve can be actuated to open and then to close, depending on the procedures desired. The resistance wire is threaded into the fiber cable to ensure effective transmission of the heat for proper release of the piston when desired.
An apparatus and method of operating devices (such as devices in a wellbore or other types of devices) utilizes actuators having expandable or contractable elements. Such expandable or contractable elements may include piezoelectric elements, magnetostrictive elements, and heat-expandable elements. Piezoelectric elements are expandable by application of an electrical voltage; magnetostrictive elements are expandable by application of a magnetic field (which may be generated by a solenoid in response to an electrical current); and heat-expandable elements are expandable by heat energy (e.g., infrared energy or microwave energy). Expandable elements are abutted to an operator member such that when the expandable element expands, the operator member is moved in a first direction, and when the expandable element contracts, the operator member moves in an opposite direction.
An improved packer (plug/bridge plug) for us in the exploitation of subterranean oil and/or gas reserves comprises a mechanism (50,52) for anchoring the packer (5) within an oil/gas well, a mechanism (55,56,60,65) for setting the anchoring means (50,52), a sealing element (180), and a mechanism for setting the sealing element, wherein the mechanism (60,65,155) for setting the anchoring means (50,52) comprises a biasing mechanism (60,65), and means (155) for releasably retaining the biasing mechanism (60, 65) in an energized state, wherein, in use, when the releasable retaining mechanism (55, 56) are released the biasing mechanism (60,65) act on the anchoring means (50,52) so as to cause the anchoring mechanism (50,52) to move into a deployed position.
An inserting device for coiled tubing comprises a top drive having a sleeve-shaped through-going shaft and an injector for coiled tubing. The coiled tubing is passed through safety valves, through a packer, as well as through a valve and further through the top drive's sleeve-shaped shaft. The coiled tubing is passed over a guide wheel. Drilling fluid is conducted to the top drive through a hose running over a caster, and a drilling fluid valve. A packer seals around the coiled tubing, and the valve is adapted to be capable of cutting the coiled tubing.
A downhole force generator includes a longitudinal force generating and transmitting assembly (including, for example, a motor and a threaded shaft that is extended and retracted by operation of the motor) adapted to be moved into a well. A controller is also adapted to be moved into the well and is connected to the longitudinal force generating and transmitting assembly. The controller includes a memory containing a program to control the longitudinal force generating and transmitting assembly to obtain at least one desired operating condition in the well. A sensor can be connected to the controller. A self-contained power source adapted to be moved into the well can also be used. A method of providing an infinitely variable linear force in an oil or gas well is a particular application for such a downhole force generator. This particular method comprises sensing in the well a parameter responsive over a continuum to changes in a selected operating condition in the well. This method further comprises actuating a microcontroller to run a predetermined program stored in the microcontroller. The program is run to obtain a specific state of the selected operating condition represented within the continuum of the sensed parameter.
A dynamic inflatable sealing device for maintaining the pressure within an inflatable element at least substantially equal to the pressure in the annulus to maintain the inflatable element in a sealing position. The dynamic sealing device includes an inflatable element forming an internal chamber, the inflatable element expandable to sealing engagement with a wall, and a dynamic valve mechanism in operational connection between the internal chamber and exterior of the internal chamber substantially communicating the pressure external of the inflatable element to the internal chamber.
