The cylinder head test stand 1 allows time-accelerated testing of the behaviour of cylinder heads for passenger car and truck engines under alternating thermal stress conditions, as occurring in hot-cold cycles of combustion engines. Both the life span up to the formation of cracks, as well as crack propagation can be examined under reproducible conditions in permanent operation. Thermo-mechanical stress is applied via specially developed regulated burner modules which simulate the application of heat generated in the combustion process of a running engine. Up to six burner modules can be positioned and regulated in the context of the geometrical and thermal conditions found in passenger car and truck engines.
While being based on the same test principle, the cylinder head test stand 2 (ZKP2) additionally features a modular test stand structure. The individual burners can be positioned more variably, so that now cylinder heads of high-power engines can be tested as well. Here, up to four burner modules can be arranged to examine the combustion chamber’s cover. The ZKP2 will furthermore also feature (as well as the ZKP1 now too) an extended burner regulation which permits realising pre-defined heating and cooling curves as well as specific temperature preservation times.
In the context of the construction of the new test stand, which will commence operation before the end of this year, a new and modern test stand building was developed which will be accommodating both test stands as of 2012.
With the cylinder head test stand, thermal stress conditions the cylinder heads are subjected to can be simulated in the laboratory in time-accelerated form. The fatigue strength can thus be verified under cyclic thermo-mechanical conditions. In contrast to conventional engine endurance runs, cylinder heads can already be tested at a very early development stage, without the complete engine being available. This takes into account the ever shorter development cycles in the automotive industry. Extensive as well as cost-intensive engine test stand runs and driving tests can thus be reduced to a minimum.
Heart of the facility is a burner unit operated with a propane oxygen mix, on which differently dimensioned cylinder heads can be tested in continuous operation with a total of six separately adaptable burners. The items under test can be heated up to operating temperature within a very short time, and be cooled down to moderate temperatures with cooling agents in freely definable and selectable cycles. Cooling is ensured via two separate cycles with different flow temperatures. Here, it is possible to perform the tests with customized cooling agents. Typical times for a complete cold-hot-cold cycle lie within a range of 60 seconds.
All components of the facility are designed for automated continuous operation, without service personnel in the test room. A camera system is installed at the test stand detecting and documenting cracks when these are occurring. The open structure makes inspections during permanent operation possible. The test stand can be fully automatically controlled via a specially designed user interface. Attached to the test room is a control room as well as a separate assembly and storage area.
As new services completing our comprehensive service portfolio with the testing of cylinder heads, we now also offer material and damage analyses of the test items in our accredited material laboratory. In addition to the testing of cylinder heads and the validation of calculation models, IABG is thus also able to perform the analysis and damage evaluation of test items.
The second cylinder head test stand is yet another milestone on IABG’s way to becoming the strategic development partner in engine construction focusing on customised one-stop services in the sectors of testing, analysis and simulation.
