Alcatraz integral multi turn (type DML/SML) valve interlocks fit on all types of manually operated valves, such as ball, plug, gate and globes.
Alcatraz Interlocks are a brand of mechanical valve interlock systems designed to enforce safe, step-by-step operation of valves and equipment. They use a trapped-key principle to ensure operator actions happen in the correct sequence and prevent human error. Each valve or device is fitted with a lock that holds or releases a uniquely coded key. The key can only be removed when the valve is in a specific position (e.g. fully closed). That key is then used to unlock the next valve in the sequence—so operators are physically guided through the correct order of operations.
