In the big top! - MAN inmotion

Technology Cold testing
Why cold is better
Every engine produced must be tested to ensure that
everything works properly. After all, customers expect to
hear the familiar MAN roar when they start up their engines,
not a feeble click. But in conventional simulations engineers
start the engine and let it run until it reaches operating
temperature before meticulously examining it. Engines thus
consume diesel and produce carbon dioxide during testing.
Preparing the engine for the test also takes a lot of
preparation (see info box to the right). So another advantage
of cold testing is its improved efficiency.
MAN first tried out the process in 2006 and has used it
increasingly ever since, thanks to its massive potential for
saving fuel and time. At the factory, around 15 workers, headed
by module manager Frank Wieczorek and segment manager
Franz Kocher, are responsible for preparing and running the
tests and making the final checks. Kocher explains: “In a cold
test, the engine does not run on its own power, but is driven
by an electric motor.” A control unit assesses the data
electronically. It comes as no surprise that shorter testing times
dramatically reduce the amount of diesel required and produce
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inmotion
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Quick overview:
How cold testing
works
It takes around half an hour of thorough testing before
each engine can prove that it meets the strict quality
criteria and will run reliably. The special thing about the
process is that the engine no longer needs to start up –
instead it’s driven by an electric motor.
1
A conveyer system transports the engines to the cold
testing area at precise intervals. There, the engine
number is scanned and saved so that the correct
parameters can be transmitted to the test stand.
2A worker prepares the engine and connects it to the
diesel line and control unit. The engine is then filled with
a small amount of diesel and the test can begin.
only a fraction of the emissions. Cold testing can check all the
engine’s general functions, too. Kocher and his staff know
exactly what they’re doing – every move they make is part of
a well-practiced routine. Once a minute an engine trundles into
the cold testing area. It is placed onto a special pallet by a crane
and then human hands are required for the only time in this
highly automated process as a worker connects the engine to
the fuel line and the control unit.
Preparation time
Infos Cold testing
Engine testing: amounts saved on average
Testing time
Diesel consumption
CO2 emissions
Hot testing Cold testing
50 minutes 29 minutes
38 minutes 3,1 minutes
approx. 25 litres approx. 2 litres
CO2 62,64 kg CO2
6,64 kg
Source: MAN PMPMMD department (cold tests on D20/D26)