A downhole deployment and isolation system may be used to deploy a completion string, service the well, and isolate the lower completion string, optionally in a single trip. The lower completion string may be run into the well with a valve in an open condition, such as a ball valve propped open by a mandrel. The mandrel may be operable to both disconnect the work string from the lower completion string and to close the valve upon disconnecting such as by removing the mandrel from the ball. The valve may be remotely reopened with fluid pressure form surface.

A downhole deployment and isolation system may be used to deploy a completion string, service the well, and isolate the lower completion string, optionally in a single trip. The lower completion string may be run into the well with a valve in an open condition, such as a ball valve propped open by a mandrel. The mandrel may be operable to both disconnect the work string from the lower completion string and to close the valve upon disconnecting such as by removing the mandrel from the ball. The valve may be remotely reopened with fluid pressure form surface.

In a subsea blowout preventer stack system with valves in the choke and kill lines with the need for failsafe operation or automatic movement of a safe position when the operating control signal is lost, a method of providing failsafe operation to the safe position comprising providing a hydraulic cylinder having a piston with a piston rod connected to the valve closure member, providing a first hydraulic supply at a first pressure to a first side of the piston to move the valve closure member to an actuated position, providing a second hydraulic supply at a second pressure lower than the first pressure to a second side of the piston to move the valve closure member to the safe position when the first hydraulic supply is removed.

In a subsea blowout preventer stack system with valves in the choke and kill lines with the need for failsafe operation or automatic movement of a safe position when the operating control signal is lost, a method of providing failsafe operation to the safe position comprising providing a hydraulic cylinder having a piston with a piston rod connected to the valve closure member, providing a first hydraulic supply at a first pressure to a first side of the piston to move the valve closure member to an actuated position, providing a second hydraulic supply at a second pressure lower than the first pressure to a second side of the piston to move the valve closure member to the safe position when the first hydraulic supply is removed.

The invention solves the problem of the difficulty of acquiring subsea variables by using a widely available surface variable, namely the pressure upstream of the choke valve. As surface variables have an unfavorable dynamic for use in conventional anti-slug controllers, which are based on the linear PID algorithm, the proposed controller uses a hybrid fuzzy-PID architecture, which compensates for the unfavorable dynamic of the controlled variable by means of heuristic interventions in the control action generated by the PID part of the controller. The heuristic action of the proposed controller allows it to be more robust than a conventional controller, even with a relatively slow control action, which makes it possible to apply the proposed algorithm in systems whose choke valve activation is slow. Thus, the two largest impediments for installation of conventional controllers, lack of subsea measurement and choke valve slowness, do not pose a problem for application of the proposed algorithm. This allows the proposed anti-slug controller to be used in offshore production systems without the need for physical intervention in the subsea or surface facilities.

The invention solves the problem of the difficulty of acquiring subsea variables by using a widely available surface variable, namely the pressure upstream of the choke valve. As surface variables have an unfavorable dynamic for use in conventional anti-slug controllers, which are based on the linear PID algorithm, the proposed controller uses a hybrid fuzzy-PID architecture, which compensates for the unfavorable dynamic of the controlled variable by means of heuristic interventions in the control action generated by the PID part of the controller. The heuristic action of the proposed controller allows it to be more robust than a conventional controller, even with a relatively slow control action, which makes it possible to apply the proposed algorithm in systems whose choke valve activation is slow. Thus, the two largest impediments for installation of conventional controllers, lack of subsea measurement and choke valve slowness, do not pose a problem for application of the proposed algorithm. This allows the proposed anti-slug controller to be used in offshore production systems without the need for physical intervention in the subsea or surface facilities.

A rotating joint apparatus includes a first section, a second section, and an interface between the first section and the second section. A bearing at the interface is configured such that the first section is rotatable relative to the second section. A main flow passage extends through the first section and the second section. A signal conductor is accessible, by a first connector on an exterior surface of the first section and, and by a second connector on an exterior surface of the second section. The signal conductor includes a signal transmission assembly at the interface.

A rotating joint apparatus includes a first section, a second section, and an interface between the first section and the second section. A bearing at the interface is configured such that the first section is rotatable relative to the second section. A main flow passage extends through the first section and the second section. A signal conductor is accessible, by a first connector on an exterior surface of the first section and, and by a second connector on an exterior surface of the second section. The signal conductor includes a signal transmission assembly at the interface.

An overpressure control apparatus is used to control jets of high-pressure fracking fluid or other stimulation fluid released from a treatment flowline in cases of overpressure. The apparatus includes a collection tank and one or more valves, which can all be mounted on or integrated to a skid. The sizes and weights of the collection tank and the skid may help to keep the apparatus on the ground during an overpressure event. The apparatus can be provided with an offline testing system that allows an operator to close off the communication between the apparatus and the treatment flowline, and instead, pump a clean fluid such as water at high-pressure to test the proper functioning of the valve.

A thermal expansion system for actuating a remote operated sleeve assembly to open and close ports in a housing for fluidly communicating between a bore of a tubular string in a wellbore to the formation utilizes actuation of a propellant charge to create expanding gas and heat in a combustion chamber to directly act on one side of a piston connected to an axially moveable sleeve supported in the housing to shift the sleeve in one direction. Ignition of another propellant charge in a combustion chamber on an opposing side of the piston is used to directly shift the sleeve in an opposing direction.