Netherlocks B.V has successfully installed 1600 safety interlocking devices at the Shell Eastern Petroleum (Pte) Ltd (SEPL) ethylene cracker complex in Pular Ular, Singapore. The main applications for the interlocks are for the decoking process, and on isolation valves for PSVs (Pressure Safety Valves). Netherlocks’ interlocks use a linear key transfer system to ensure that processes can only be carried out in the correct order, ensuring each part has been safely completed before the next can be started. Safely completing the previous step in the process sequence will release a unique key that then unlocks the next step; only when a mistake is made will the operator be prevented from proceeding by a key that doesn’t fit or a valve locked in position. Projected to produce 800kt/a of ethylene, 450kt/a of propylene and 230kt/a of benzene, the facility consists of an ethylene cracker unit, a pygas hydrogenation/benzene extraction unit, a C4 selective hydrogenation unit and various associated utilities. Opened in March 2010, the complex links the nearby SEPL Refinery with downstream chemical units, forming an integrated petrochemical ‘super site’ in Singapore.