WÄRTSILÄ WARTSILA 50DF, Product Manual

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Remarks:
Additional properties specified by Wärtsilä, which are not included in the ISO specification. 1)
Max. 1010 kg/m³ at 15°C provided that the fuel treatment system can remove water and solids (sediment, sodium, aluminium,
silicon) before the engine to specified levels. 2)
Straight run residues show CCAI values in the 770 to 840 range and have very good ignition quality. Cracked residues delivered
as bunkers may range from 840 to - in exceptional cases - above 900. Most bunkers remain in the max. 850 to 870 range at
the moment. CCAI value cannot always be considered as an accurate tool to determine the ignition properties of the fuel,
especially concerning fuels originating from modern and more complex refinery process.
3)
The max. sulphur content must be defined in accordance with relevant statutory limitations.
4)
Sodium contributes to hot corrosion on the exhaust valves when combined with high sulphur and vanadium contents. Sodium
also strongly contributes to fouling of the exhaust gas turbine blading at high loads. The aggressiveness of the fuel depends
on its proportions of sodium and vanadium and also on the total amount of ash. Hot corrosion and deposit formation are,
however, also influenced by other ash constituents. It is therefore difficult to set strict limits based only on the sodium and
vanadium content of the fuel. Also a fuel with lower sodium and vanadium contents than specified above, can cause hot
corrosion on engine components. 5)
The implementation date for compliance with the limit shall be 1 July 2012. Until that, the specified value is given for guidance.
6)
It shall be ensured that the pour point is suitable for the equipment on board, especially if the ship operates in cold climates.
7)
The fuel shall be free from used lubricating oil (ULO). A fuel shall be considered to contain ULO when either one of the following
conditions is met:
●
Calcium > 30 mg/kg and zinc > 15 mg/kg
●
Calcium > 30 mg/kg and phosphorus > 15 mg/kg
8)
6-4 Wärtsilä 50DF Product Guide - a16 - 9 September 2016
Wärtsilä 50DF Product Guide 6. Fuel System