Abstract: A tubing pressure insensitive actuator system includes a housing having a bore therein. A force transmitter is sealingly moveable within the bore, the force transmitter defining with the bore two fluid chambers. One of the fluid chambers is at each longitudinal end of the force transmitter. At least two seals are sealingly positioned between the housing and the force transmitter, with one of the seals isolating one end of the force transmitter from tubing pressure and another of the seals isolating another end of the force transmitter from tubing pressure. A method is also included.

Abstract: A control system for a subsurface safety valve addresses normal open and closed operation and a failsafe operation if key system components fail. It features a single control line from the surface that splits at the subsurface safety valve and goes to one end of two discrete piston chambers that are aligned and isolated from tubing pressure. The piston in one chamber is larger than in the other and the pistons are connected for tandem movement. Each side of the unbalanced system's piston has a seal mounted to it and another for the rod attached to it that exits the chamber. A jumper line connects the chambers at a point between the seals in each chamber and features a large reservoir. The jumper line is filled with a compressible fluid. Fail safe closure of the valve occurs if any of the four seals fail.

Abstract: Systems for operating one or more sliding sleeve valves in an incremental, step-type fashion between open and closed positions, permitting the valve or valves to be choked to progressively smaller flow areas. The systems of the present invention also permit the valve or valves to be fully closed without having to progress through incremental steps.

Abstract: A tubing pressure insensitive actuator system includes a housing having a bore therein; a force transmitter sealingly moveable within the bore the force transmitter defining with the bore two fluid chambers, one at each longitudinal end of the force transmitter; and at least two seals sealingly positioned between the housing and the force transmitter, one of the seals isolating one end of the force transmitter from tubing pressure and another of the seals isolating another end of the force transmitter from tubing pressure and method.

Abstract: A control system can be used with a single control line to a subsurface safety valve. The operating piston is exposed to the flow tube between two blocks with near identical seals to make the piston insensitive to tubing pressure. A control system seal is carried by the piston in the upper block and a passage between the control system seal and the tubing pressure seal in the upper block communicates to a compressible fluid reservoir in the lower block that is also isolated from tubing pressure by a tubing pressure seal. Movement of the piston compresses the fluid in the reservoir. The reservoir can also include a spring to return the piston and the flow tube to a position to close the valve. A redundant system can be actuated if the primary system fails.

Abstract: A control system can be used with a single control line to a subsurface safety valve. The operating piston is exposed to the flow tube between two blocks with near identical seals to make the piston insensitive to tubing pressure. A control system seal is carried by the piston in the upper block and a passage between the control system seal and the tubing pressure seal in the upper block communicates to a compressible fluid reservoir in the lower block that is also isolated from tubing pressure by a tubing pressure seal. Movement of the piston compresses the fluid in the reservoir. The reservoir can also include a spring to return the piston and the flow tube to a position to close the valve. A redundant system can be actuated if the primary system fails.

Abstract: A control system for a subsurface safety valve addresses normal open and closed operation and a failsafe operation if key system components fail. It features a single control line from the surface that splits at the subsurface safety valve and goes to one end of two discrete piston chambers that are aligned and isolated from tubing pressure. The piston in one chamber is larger than in the other and the pistons are connected for tandem movement. Each side of the unbalanced system's piston has a seal mounted to it and another for the rod attached to it that exits the chamber. A jumper line connects the chambers at a point between the seals in each chamber and features a large reservoir. The jumper line is filled with a compressible fluid. Fail safe closure of the valve occurs if any of the four seals fail.