A LARGE GATE ISOLATION VALVE, PARTICULARLY FOR VACUUM SYSTEMS FOR NUCLEAR FUSION MACHINES AND SIMILAR USES

摘要

A large isolation valve, particularly for vacuum systems for nuclear fusion plants and similar uses, includes a body (2) with two annular valve seats (9) which cooperate with two obturators (5) carried by a gate unit (4). Actuators (16, 18) for moving the obturators (5) and the valve seats (9) towards and away from each other are separate from and independent of the actuators (6, 12) for moving the gate unit (4) and include a ring of thrust springs (16) which act so as to move the two obturators (5) apart axially towards the closure position, and a ring of pressurised-fluid actuators (18) which can be activated in order to move the two obturators (5) together axially towards the open position.