Rørhenger til bruk i et brønnhode samt fremgangsmåte for å låse en rørhenger i et brønnhode

An annulus isolation valve comprises a valve actuation bore and a flow passage capable of providing fluid communication between an upper annulus and a lower annulus. The flow passage comprises a first flow path and a portion of the valve actuation bore. Further, the first flow path has a second longitudinal axis that is different from a first longitudinal axis. The annulus isolation valve further includes a plug gate positioned in the valve actuation bore. The plug gate is configured so that in the open position it allows fluid communication between the upper annulus and the lower annulus. The annulus isolation valve further includes a biasing mechanism positioned in the valve actuation bore. The biasing mechanism is capable of forcing the plug gate into the closed position when the actuation force is not applied.