Abstract: Remote control of hydraulically set packers is achieved by incorporating a hydraulic energy accumulator into a well tubing string. A hydraulic line connecting the accumulator with the packers setting mechanism is blocked by a shearable plug connected between the accumulator body and a movable control sleeve. In one embodiment, upward force exerted on the cable of a shifting tool latched into the control sleeve causes the plug to shear and pressure from the accumulator to set the packers. In another, the plug is sheared by movement of the sleeve through contact with a pressure differential sensitive piston that shifts in response to an increase in annular pressure.

Abstract: In accordance with an illustrative embodiment of the present invention, a valve placed in a subsea blowout preventer stack during a production test of a well producing gas comprises a valve body containing two valve elements in series and a releasable control unit. A fluid to inhibit the formation of natural-gas hydrates can be injected into the valve body by means of a pump on the surface and through a high-pressure hose. A lateral connector fixed to the control unit is fitted in a sealed manner into a receptacle on the valve body to allow reconnection of the inhibiting fluid injection system.