Annulus valve for concentric tubing hangers

Abstract From the Canadian patent

An improved valve for controlling flow through a tubing hanger in a unit having a concentric tubing system and includes upwardly facing recesses or blind pockets in the hanger with a valve member in each of said pockets and having circumferential seals around its upper end and around its lower enlarged end, the valve members are biased upwardly in their pockets by springs and by annulus pressure which is transmitted to the lower end of the valve members through valve passages, the valve members each includes an upper projection or rod which is engaged by an annular actuator controlled responsive to a downwardly exerted spring force and by a pressure area differential which is exposed to …