How it improves performance

The AFIV™ annulus-controlled shrouded isolation valve features a robust shutoff sleeve to separate production from the upper and lower zones in intelligent completions. The sleeve controls fluid from the upper zone, which flows through the valve's internal annulus. Fluid from the lower zone passes unobstructed through the valve ID. 

The AFIV valve prevents formation damage resulting from fluid loss during completion operations. It provides a fluid isolation barrier for the upper zone, separating it from the lower zone, which is protected by a second isolation valve (ball valve) while production tubing is run. By separating the two zones, the valve enhances production, simplifies completion operations, and increases wellbore safety.

How it works

The AFIV valve can be opened remotely one time using the Trip Saver mechanism, which is triggered by cycles of pressure applied to the valve's inner annulus. These pressure cycles act against a precharged nitrogen chamber and are counted by an integral indexing mechanism. After 10 or 15 cycles, depending on the preselected option, the nitrogen pressure acts against hydrostatic pressure and generates the force required to open the valve.

The nitrogen charge is selected to optimize valve actuation based on well conditions. The 15-cycle Trip Saver mechanism enables greater flexibility in completion operations.

An integral mechanical shifting profile allows the valve to be mechanically opened and closed multiple times using a shifting tool run at the end of washpipe, wireline, or coiled tubing. When the shifting tool passes through the valve, it engages the shifting profile and the shutoff sleeve either opens or closes. A permanent lockout feature locks the mechanical section of the valve in the open position once the Trip Saver mechanism is actuated, preventing inadvertent valve closure.

Additional Information

The AFIV valve Model C incorporates a compensating piston that uses hydrostatic pressure to enhance the nitrogen force. This design enables using a lower surface charging pressure while ensuring that sufficient force is available downhole for valve actuation. The Model C valve is suitable for high-hydrostatic-pressure or low-temperature downhole environments.