Safety device for operation of valves comprises locking rod controlled by locking part with locking bolt movable by key which can only be withdrawn when bolt is in unlocked position

摘要

The safety device for the operation of a valve (20) comprises a valve locking rod (24). A rod locking part (30) moves between an end locking position and a rod release position. A locking device (44) for the locking part comprises a bolt movable under the action of a removable key. The key can only be withdrawn from the locking device when the bolt is out of the locking position. A hole receiving the bolt in its unlocked position is only opposite the bolt when the locking part is in its end locking position so as to prevent the extraction of the key when the locking part is not in its locking position.