The pump-through flapper safety valve (PFSV) provides a reliable means for obtaining downhole shut-in and minimizing wellbore storage during final pressure buildup. It also has the ability to pump into the formation, irrespective of tubing or annulus pressure integrity above the valve.
The PFSV is a fully opening downhole safety valve. It is open when run in the hole and closed permanently when annulus pressure rises above the rupture disk rating. The operator mandrel is biased to internal pressure and locked in the open position to prevent premature closure. Upon bursting the rupture disk, hydrostatic pressure is applied to the operator mandrel, which moves up against an atmospheric chamber, uncovering the spring-loaded flapper. Pumping down the tubing lifts the flapper off its seat and permits killing the well.
Request More Information
|