In some IC engines, fuel injection pump is driven by camshaft; thus, these camshafts are designed for bending and torsional loads. Conventionally, camshafts are built-to-specification. Typically, durability assessment of camshaft happens at engine level, this calls for proto or calibration engine to be made and available for testing. As there are limited number of engine level proto testing, the overall scatter in camshafts due to manufacturing/process variations is not possible to be covered. This poses a risk of camshaft failures in the final stages of product development. To mitigate this risk, a component level standard test method is needed for quickly validating design and manufacturing process of camshafts for second source suppliers.
The current paper discusses the process followed for arriving at a standard test setup and overcoming the challenges in terms of capturing the appropriate physics for camshaft failure during the engine level testing. Camshaft rear end experiences bending load due to FIP operation. The component level testing method is established by ensuring load and bending moment, and it is used for validating improvements done on manufacturing process and design quickly with confidence for design implementation approval for a test concern. To gain confidence on test outcomes, strain measurement is performed on camshaft with the proposed test setup and found to have more than 98% correlation with CAE results. This newly developed test methodology is added as a DVP requirement for all upcoming projects. It has benefited from time savings of around 120 days per project for camshaft testing.