Caterpillar Marine - Marine Engines Caterpillar

enging circuit makes it possible to
keep the entire fuel system (high- and
low-pressure system) in a pre-heated
condition and ensures reliable HFO
operation.
n Injectors Caterpillar opted for a
simple, robust, compact approach by
using the fuel itself for controlling the
injectors, thereby obviating the need
for a separate control fluid. The cooling
of the injection nozzle by means of
lube oil is another typical characteristic
of HFO operation. For CCR the lube oil
circuit has meanwhile been expanded
to cool the electrical components
within the injector and thus increase
service life. The injection process is
electronically controlled and permits
flexible timing from the beginning
Injector
including the capability for multiple
injection. The injection profile and the
shaping of the injection process were
optimised using the combustion modelling
available with the Caterpillar
CAT-3D software, as well as comprehensive
engine testing.
n Electronics The key component of
the CCR system is the proprietary electronic
ADEM control module. The
ADEM control system, pioneered by
Caterpillar as a trail-blazing innovation
almost 20 years ago, controls fuel
delivery, air supply and other basic
engine processes, thereby achieving
an optimal balance between performance
and emissions. The tailor-made
software for MaK engines with CCR is
based on Caterpillar's wealth of experience
gained with the existing ADEM
software and various engine control
strategies and also takes into consideration
the specific requirements of
HFO operation with medium-speed
engines. The functions of ADEM can
be basically subdivided into a core
system and a performance system.
The core system comprises the actual
control unit, a crankshaft speed
pickup, two camshaft speed pickups,
two high-pressure sensors, two intake
throttles and the injectors. The performance
system ensures an optimal
setting of the engine under all operating
conditions using information such
as exhaust gas temperature, charge
air pressure, ambient conditions and
lube oil temperature.
Safety and reliability –
a matter of course
The focus was on safety and reliability
during the entire development
process. Ulrich Hopmann, Engineering
Supervisor CCR, Caterpillar Motoren
GmbH & Co. KG (Kiel, Germany), points
out in this connection that “CCR offers
a state-of-the-art design by ensuring
engine operation with proven technology
(ADEM control unit), specific
innovations (injectors) and redundant
components (high-pressure pumps,
double-walled lines and rails, speed
pickups, pressure sensors).” A safety
gear between pumps and engine, a
pressure relief valve and flow limiters
between rail and injectors further
enhance the operating reliability of the
CCR system.
CCR – the ultimate solution
Dr. Udo Schlemmer-Kelling, Manager
Research, Caterpillar Motoren GmbH
& Co. KG (Kiel, Germany), describes the
current CCR technology for mediumspeed
engines as the result of a long
successful period of basic research and
comprehensive pre-field testing. “A
common rail solution for MaK engines
was tested as early as 1988, and socalled
unit pumps with electronically
controlled solenoid valves were developed
in 1995,” recalls Schlemmer-Kelling.
The first MaK common rail concept
was formulated at the dawn of the new
millennium and finally led to the official
launch of CCR at SMM 2006.
Dr. Frank Starke: “Another important
lesson that we have meanwhile
learned is the retrofit aspect, which
makes it possible to install the entire
system in any existing MaK M 32 C
engine already in operation.“
New Technology
Thanks to the closed loop, the electronically
controlled injection system
provides long-term stable operation
and emission values compared with
mechanical solutions. Moreover, the
injection mapping has the potential
to respond to the wear and tear
of an older engine by using modified
control parameters, which are implemented
during regular engine maintenance.
“CCR combined with FCTcontrolled
valve activation offers an
almost unlimited degree of freedom
for engine optimisation and control,“
concludes Frank Starke.
A Caterpillar Common Rail
CCR is the result of extensive
research into system stability and
service life with HFO operation and a
prudent assessment of the experience
gained in the field with competing
solutions. It combines innovative technology
with a level of reliability that is
unprecedented for the sector. The MaK
6 M 32 CCR marine engine presented
at SMM 2006 opens up a new chapter
in the long Cat and MaK success story.
And we are only at the beginning of
an exciting development: starting
with MaK M 32 series, CCR will be provided
in future for the entire range of
medium-speed MaK engines, with the
M 20 C, M 25, M 32 C and M 43 C.
Initial customer responses to the
official launch of CCR have been very
encouraging. According to Jaime
Tetrault, Manager Europe Africa
Middle East Marine, Caterpillar Marine
Power Systems, Hamburg, Germany,
CCR technology is now also being
considered for cruise ships operating
in emission-sensitive areas and
cargo vessels with gensets running
continuously during loading and
unloading routines in port: “Caterpillar
Marine Power Systems is confident
of being able to conclude further
contracts for MaK engines based
on CCR.”
High performance, low fuel consumption
and minimised emissions
are thus no longer mutually exclusive
parameters. With Caterpillar Common
Rail, MaK marine engines have certainly
taken a great step forward!
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