ESD systems on gas-fuelled ships
The hardwired emergency shutdown architecture on a gas-fuelled ship, its automatic and manual triggers, and the ship to shore link during bunkering.
The emergency shutdown system on a gas-fuelled ship isolates the gas fuel supply automatically on any safety-critical exceedance and manually from several stations. Its defining characteristic is that the logic is hardwired and fail-safe, so loss of power or loss of signal drives every actuator to the closed position rather than leaving it where it was.
During bunkering the system extends beyond the ship. The receiving vessel and the bunker source are linked so that activation on either side closes valves on both, and a mechanical breakaway coupling in the transfer hose parts and seals if the ships separate before the link can act.
The full article will cover the trigger list, the shutdown levels and what each isolates, the closing time requirements, the ship to shore link and its standards, the breakaway coupling, functional safety levels applied to the isolation function, and the survey testing of every initiator. See LNG fuel system .