4.11
Fuel system
The fuel system supplies the injection valves of the cylinders with the applicable quantity of fuel.
For the schematic diagrams, refer to section
13.1 Schematic diagrams - general
.
The fuel system has the engine connections as interface to the plant as follows (in
and
marked with a circle):
•
Connection 49 (fuel inlet)
•
Connection 50 (fuel return outlet)
•
Connection 51 (fuel leakage rail unit outlet)
•
Connection 52 (fuel leakage outlet)
•
Connection 57 (leakage outlet)
•
Connection 59 (trace heating fuel inlet)
•
Connection 60 (trace heating fuel outlet)
•
Connection 67 (fire extinguishing plant cylinder block inlet).
The constant flow of fuel through the fuel system keeps the fuel warm.
At low load the ECS automatically cuts out injection valves in each cylinder as follows:
•
For an engine with two injection valves - one of the two injection valves
•
For an engine with three injection valves - one or two of the three injection valves.
This makes sure that the engine has the best fuel and combustion properties, which decreases
smoke and fuel consumption. The ECS cuts out a different injection valve at regular intervals to
get an equal thermal load in the combustion chamber. There is no time limit to operate the engine
at low load.
The fuel system has the parts that follow:
•
Fuel pipes
The fuel pipes connect the items of the fuel system. All the fuel pipes have a trace heating
to keep the fuel warm during operation and for short engine stops. The high pressure fuel
pipes that are not in the rail unit have a double wall design and leakage inspection points.
•
Pressure retaining valve
The adjustable pressure retaining valve (009) in the return pipe keeps the fuel pressure in
the supply pipe to the fuel pumps at the correct value.
•
Supply unit
The supply unit (007) holds the fuel pumps and the related items.
•
Fuel pump (number related to the configuration)
The fuel pumps (008) supply the fuel rail with fuel at up to 1000 bar.
•
Fuel rail
Depending on the specific engine the fuel rail (004) supplies the flow limiting valves or the
injection control units with fuel.
•
Non-return valve
The non-return valves prevent fuel flow back from the fuel rail to the fuel pumps (eg if a fuel
pump has no delivery, or a fuel pipe is defective).
X72-B
AA00-0000-00AAA-043E-A
Operation Manual
Fuel system
Winterthur Gas & Diesel Ltd.
- 92 -
Issue 003 2021-12
