Online PDF Scania DI16 Fuel system Installation Manual
If the fuel tank is placed higher than the engine feed pump, a shut-off cock should be installed in the fuel line to the feed pump. During downtime, this cock should be closed. Maximum permitted fuel level in the fuel tank is 3.5 m in relation to the feed pump.
The fuel tank must not be positioned so low that the vacuum in feed pump suction pipe is greater than 0.3 bar. The risk of air leaks in the suction pipe increases with increased vacuum. See also the section Flow and pressure.
If the fuel tank is mounted so low that the maximum permissible vacuum is exceeded, or if a large fuel tank is required which cannot be mounted close to the engine, a buffer tank must be installed at a suitable distance and height. A feed pump must be fitted directly downstream of the tank. The flow for the auxiliary feed pump must be minimum 15% higher than the flows specified in the Feed pump flow rates section.
If a reliable and quick starting response is required, the buffer tank should be positioned adjacent to the engine with the lowest fuel level at the same level as the feed pump. If the fuel tank(s) are built in, the space should be well ventilated. The fuel tank should normally be drained once a year, but this may vary depending on the quality of the fuel.
Table Of Contents
Fuel tank. .........3
Position. ...... 3
Fuel tank design . .......... 4
Main tank and buffer tank . ........ 4
Fuel pipes. ........5
Minimum inside diameter of fuel lines . ...... 5
Fuel filter. ........6
PDE and XPI engines. .. 6
PDE engines . ................ 8
XPI engines . ................. 9
Fuel cooler. ....10
Feed pump flow rates. ....11
PDE engines . .............. 11
XPI engines . ............... 11
Flow and pressure . .........12
PDE engines . .. 12
XPI engines . ... 12
Risk of fire. ....13
Fuel grade and power for PDE engines. ......14
Important data. ...............16
Example of a fuel tank installation.
1. Bleed pipe.
2. Fuel filler pipe with filler cap.
3. Lead-through sleeve of fuel-resistant rubber.
4. Inspection hatch.
5. Baffle plate.
6. Fuel cocks.
8. Drain tap for sludge and water.
9. Suction pipe with strainer.
10. Return pipe. Note: For XPI engines, it should enter below the lowest fuel level.
11. Ground connection.
Main tank and buffer tank
If the engine installation has a buffer tank and main tank, these should be designed as follows:
-The main tank must have a sloped bottom or be on a slight incline (about 3-5°) and have a tap at the lowest part for draining condensation.
-The pipe fittings must be connected or routed to approximately 50 mm from the bottom and supplied with a bottom strainer. This applies to both the buffer tank and the main tank.
-The lines to the buffer tank should be as short as possible and should be mounted in such a way that they cannot be exposed to mechanical damage.
-Transfer of fuel from the main tank to the buffer tank should be achieved using an electric pump connected so that it only pumps when the engine is running. This is to prevent the risk of serious leakage when the engine is not running. The electric pump must have an excess capacity of 30-40% in relation to the engine fuel consumption. This is to ensure that the quantity of return fuel is sufficient for lubrication and cooling.
-There must be a return pipe from the buffer tank to the main tank so that any surplus fuel runs back to the main tank.
-For PDE engines, the return pipe from the engine must be routed to the upper part of the buffer tank.
-For XPI engines, the return pipe should enter below the lowest fuel level in the main tank.
-The buffer tank must also be fitted with a drain tap for condensation.
See instructions in the Fuel tank design section for further details.
The fuel tanks must be fully welded, and should have internal baffle plates to prevent the fuel being thrown about in heavy seas. Both fuel filling components and the fuel tank must be grounded to prevent sparking from static electricity. The fuel tank must have the following devices:
-A drain tap for emptying sludge and water that has sunk to the bottom.
-A ventilation or bleed line from the upper part of the fuel tank to the outside of the hull. It should be designed so that water cannot enter and so that fuel cannot run out when the ship is leaning heavily.
-Protection or filter to prevent contaminants entering during filling.
-There must always be a fuel cock in the suction line and in the return line if its outlet in the tank is higher than the outlet from the engine. The return line should be routed to the upper part of the fuel tank.
-Main tanks must be fitted with inspection hatches so that they can be inspected and cleaned inside.
New fuel tanks must be thoroughly cleaned and rinsed internally using clean fuel. They must also be pressure tested to 0.3 bar.
Fuel tanks manufactured from materials which are not resistant to corrosion must be treated externally with corrosion protection. The fuel tanks must not be painted internally nor be zinc-coated or galvanised.