Figure 6.8
Fuel oil viscosity-temperature diagram for determining the pre-heating temperatures of fuel oils (4V92G0071b)
Example 1:
A fuel oil with a viscosity of 380 cSt (A) at 50°C (B) or 80 cSt at 80°C (C) must be pre-heated
to 115 - 130°C (D-E) before the fuel injection pumps, to 98°C (F) at the separator and to minimum 40°C (G)
in the storage tanks. The fuel oil may not be pumpable below 36°C (H).
To obtain temperatures for intermediate viscosities, draw a line from the known viscosity/temperature point
in parallel to the nearest viscosity/temperature line in the diagram.
Example 2:
Known viscosity 60 cSt at 50°C (K). The following can be read along the dotted line: viscosity
at 80°C = 20 cSt, temperature at fuel injection pumps 74 - 87°C, separating temperature 86°C, minimum
storage tank temperature 28°C.
Fuel tanks
The fuel oil is first transferred from the bunker tanks to settling tanks for initial separation of sludge and
water. After centrifuging the fuel oil is transferred to day tanks, from which fuel is supplied to the engines.
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Product Guide Wärtsilä 34DF - 3/2012
Product Guide
6. Fuel System
