Abstract
As commonly known brake systems are complex systems with multiple requirements regarding friction performance, wear and noise properties. Therefore intensive investigation and testing has to be done during friction material development programs or adaptation projects to specific vehicles. Standard test methods have been developed for the determination of chemical and physical friction material properties, as well as dyno test procedures and last not least full car testing within the system environment. While these tests on final parts require a high level of resources and testing time, they are typically done during development phase and launch phase, but time constrains become critical for serial production verification. To shorten testing in serial production key characteristic have been defined, that can be verified in a reduced test setup for the serial production release, but there stays a key dilemma. With the concept that verification is done by testing the final product at the end of the production process, it is obvious, that identifying any deviation at this stage of production is far too late and will directly impact delivery and cost. Considering that the main task of all quality controls on serial production is the verification, that the pads are “identical” to the status of the friction pads as homologated, an alternative concept should be considered. By focussing on the verification of the process inputs and process controls, the concept can be used as the enabler to ensure “identical” production leading to “identical” products. In the paper this alternative or additional concept will be discussed, moving from a “Product control” to a “Process control” QC process to ensure the production of “identical” friction pads.
KEYWORDS – Brake Pads, Product Control, Process Control, fingerprinting