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Green Engines

 The ‘G’ prefix before an engine means it has a design that follows the principles of the large-bore, Mark 9 engine series that MAN Diesel & Turbo introduced in 2006 with an ultra-long stroke that reduces engine speed, thereby paving the way for ship designs with unprecedented high-efficiency.

Specification of G-80ME-C9
            ▪    Power kW/cyl    : 4,450
            ▪    Engine speed rpm    : 68
            ▪    Stroke mm        : 3.720
            ▪    MEP bar        : 21
            ▪    Mean piston speed m/s    : 8.43
            ▪    Length mm (7 cylinder)     : 12.500
            ▪    Dry mass ton (7 cylinder)    : 960
            ▪    SFOC, L1 (g/kWh)        : 167

The G-type achieves SFOC reductions through a combination of several factors, such as:
            ▪    increased scavenge-air pressure
            ▪    reduced compression ratio (twostroke Miller timing)
            ▪    increased maximum combustion pressure
            ▪    adjustments of compression volume and design changes.

The G-type engine is characterised by:
  • low SFOC and superior performanceparameters thanks to variable,electronically controlled timing of fuelinjection and exhaust valves at anyengine speed and loadappropriate fuel injection pressureand rate shaping at any engine speedload
  • flexible emission characteristics withlow NOx and smokeless operation
  • perfect engine balance with equalisedthermal load in and betweencylinders
  • better acceleration in ahead andastern operation and crash stop situations
  • wider operating margins in terms ofspeed and power combustions
  • longer time between overhauls
  • very low speed possible even forextended duration and Super DeadSlow operation manoeuvring
  • individually tailored operating modesduring operationfully integrated Alpha Cylinder Lubricators,with lower cylinder oil consumption
  • an engine design lighter than its mechanicalcounterpart.


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