Economiser design change

A fire on a roro passenger ferry has caused the Marine Accident Investigation Branch of the UK government?s Department of Transport to suggest designing economiser systems with separate drain valves so that the system can be totally emptied for maintenance.

The fire started after oil that had escaped from a thermal oil-filled economiser onto exhaust trunk lagging during the economiser?s repair, ignited. The oil escaped during the repair of a quick closing valve on which the valve spindle had become detached from the valve lid. The defect meant a gauge line from the economiser?s flow meter had to be used to drain the oil in order to repair the valve. This technique, however, was unable to fully drain the economiser. Although care was taken to clean up most of the spilt oil from the lagging, a fire started in the uptakes and funnel casing shortly after the ship left port. The crew extinguished the fire.

“The design of the economiser system would have been greatly improved by having a separate drain valve, which could totally empty the system for maintenance,” says the MAIBs report into the incident.