Smith Flow Control has introduced an Anti-Tamper Lock (ATL) to ensure that valves and actuators are operated only by authorised individuals. The ATL aims to reduce the risk of human error or deliberate tampering. The standard condition of the device in service is locked (key-free), with the handwheel free-rotating. Operation involves three steps: first, a coded key from the control authority is inserted, engaging the drive; secondly, the valve is operated to the desired position; finally, the key is removed and the valve is locked in the desired position. The ATL’s housing is stainless steel coated with yellow polyester resin. For safety applications the internal components are manufactured from stainless steel 304, with acetyl bearings, while for security applications these components are manufactured from hardened steel, with a protective security “skirt”. Both versions can operate in temperatures ranging from –50 C to +100 C.
