DESCRIZIONE
A valve assembly (1) has a valve (14), for example a flapper valve, that is contained within an axially movable valve housing (11) in the form of a cartridge (10) that is received within the bore of a tubular member (5). More than one cartridge (10) may be connected in series. The valve (14) and cartridge (10) are pivotally connected (13) and axial movement of the cartridge (10) pivots the valve (14) around this connection (13) to open or close the valve (14). The valve assembly (1) can be actuated by an actuator assembly (50) having an actuator (61) for actuating the valve (14), and a resettable shuttle device (80) that retains the actuator (61) in different configurations within the actuator assembly (50). The actuator (61) can be moved relative to the valve (14), engaging the shuttle device (80) and changing the configuration of the shuttle device (80).