D6E Diesel Used Engine Assembly For Excavator EC220DLR Electric
Specification
| Car name: Engine Assy | Model Number: D6E |
| Cylinder stroke: 126 | Cylinder diameter: 98 |
| Application: Excavator | valve: 12 valve |
| Cooling: Water cooling | Injection: Electric |
| Number of Cylinders: 6 | Engine Type: Diesel |
Description
Advancing (injecting when the piston is further away from TDC) the
start of injection results in higher in-cylinder pressure and
higher efficiency but also results in higher Nitrous Oxide (NOx
[2]) emissions. At the other extreme, very retarded start of
injection or timing causes incomplete combustion. This results in
higher Particulate Matter (PM) emissions and higher smoke.
Fuel injection in diesel engines
Early diesels often employed indirect injection in order to use
simple, flat-top pistons, and made the positioning of the early,
bulky diesel injectors easier, but all modern diesel engines employ
some form of direct injection, coupled with more complicated
bowl-in-piston designs. Modern engines also use a very highly
pressurised fuel supply line, which replaces the older, noisier,
and mechanically more complicated combined pump and selector valve
assembly.
Indirect Injection
An indirect injection diesel engine delivers fuel into a chamber
off the combustion chamber, called a prechamber, where combustion
begins and then spreads into the main combustion chamber. The
prechamber is carefully designed to ensure adequate mixing of the
atomized fuel with the compression-heated air. This has the effect
of slowing the rate of combustion, which tends to reduce audible
noise. It also softens the shock of combustion and produces lower
stresses on the engine components. The addition of a prechamber,
however, increases heat loss to the cooling system and thereby
lowers engine efficiency.
Direct injection
Modern diesel engines make use of one of the following direct
injection methods:
Common rail direct injection
In older diesel engines, a distributor-type injection pump,
regulated by the engine, supplies bursts of fuel to injectors which
are simply nozzles through which the diesel is sprayed into the
engine's combustion chamber. As the fuel is at low pressure and
there cannot be precise control of fuel delivery, the spray is
relatively coarse and the combustion process is relatively crude
and inefficient.
