MAN approves Lemag fuel switch system

Lemag's CONTROLmag ensures a safe and steady switchover between residual and distillate fuels Lemag's CONTROLmag ensures a safe and steady switchover between residual and distillate fuels
Industry Database

Lemag, Lehmann & Michels has received a letter of no objection from MAN Diesel & Turbo for the use of its CONTROLmag fuel switching system with MAN engines.

The Hamburg-based manufacturer was asked by MAN to design the system, allowing safe changeover from heavy fuel oil (HFO) to marine distillate oil (MDO) and back again, in 2008.

The Lemag system controls the fuel changeover process – when vessels are coming into and out of Emission Control Areas for example – by regulating the speed at which temperature of fuel is raised (when switching to HFO) and lowered. The design includes a DIESELswitch changeover valve, sealed with magnetic coupling, with a feedback sensor over the rotor position.

Three special valve designs also enable changeover when the HFO and MDO tanks have different tank levels. A difference of 20m in tank level can be accommodated. In total more than 50 alarm systems control the process and protect the engine.

Another feature of the changeover system is backup storage of the time – and, as an option, the GPS position – at which changeovers were made. The data is stored on a data logger that cannot be manipulated, but is available for port state control to read. Data is logged at the beginning of the changeover, when the HFO valve is closed and when flushing is theoretically completed.

The system is available in several variations, from a low-budget standard version to a system with full control of the fuel consumption, using Coriolis flow meters to measure the amount of HFO and MDO coming from the service tanks. The system can be operated either from the engine control room, or directly.

Other options include the supply of dosage and blending equipment for fuel additives, which can be automatically switched during the changeover process to prevent incompatible fuels from flocking. A system to enhance lubrication dosage during MDO operation is also available.

Several patents are registered in relation to the CONTROLmag. The company noted that the letter of no objection from MAN represents a valuable and timely opportunity, with ship owners exploring avenues for managing the potentially complicated changeover process from high-sulphur residual fuel to low-sulphur distillate in Emission Control Areas since 1 January.

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