Alcatraz Interlocks introduced world’s smallest multi turn valve interlocks. These are specially designed to fit on all small types of hand wheel operated valves such as gate and globe valves, bar stock, screwed or bolted bonnet valves. They are mounted on multi-turn valves to interlock the locked open and/or locked closed position of the valve. Only if both keys are inserted in the lock portions the valve can be operated. The first key can only be released in the fully open position the other key can only be released in the fully closed position.
Their applications include requiring throttling and frequent operation and on off applications so called Shut off. For example, globe valves or valves with a similar mechanism may be used as sampling valves, which are normally shut except when liquid samples are being taken.