MECHANICAL valve control equipment company Smith Flow Control has supplied its valve interlocks to all three Curtis Island projects, helping project developers to protect workers and streamline processes.

BG Group’s Queensland Curtis LNG, Santos’s Gladstone LNG and Origin Energy’s Australia Pacific LNG use the interlocks to protect against the over-pressurisation of vessels by ensuring an open path to pressure relief is maintained at all times during maintenance or other safety critical processes.

Interlock systems ensure that no relief valve can be isolated until a spare relief valve has been brought on-stream, providing capacity to enable continuous production while maintenance procedures take place.

These systems were also specified on pig launchers and receivers, preventing the pig trap door being opened under pressure – an event which could lead to the pig shooting out at high speed.

Key interlocks negate this risk by mechanically proving the ‘closed and isolated’ status that enables venting and draining of pig trap vessels before loading or unloading operations commence.

By fitting an interlock to the pig trap door, valves and other equipment on the vessel, it ensures that only the correct sequence of operation can occur.

Smith, a subsidiary of Halma, offers a range of valve management systems for arduous operational requirements, including portable valve actuators that can enable one operator to work banks of valves efficiently.