Subramanian, D., Sridhar, N., Karthikeyan, N., and Chandra, V., "Reliability Testing: Predictor Effect Analysis on Engine Mounts," SAE Technical Paper 2015-01-2757, 2015, doi:10.4271/2015-01-2757.
The Indian automotive sector is experiencing a major shift, focusing predominantly towards the levels of quality, reliability and comfort delivered to the customer. Since the entry of global players into the market, there is a rising demand for timely product launches with utmost priority to reliability. In any vehicle, engine isolation systems play a critical role in isolating the engine vibrations from the vehicle chassis. This project details on how testing can aid in reducing the launch time as well as estimating the reliability of the component when used in a different application/vehicle. It proposes a methodology to formulate a life model for the engine mount considering various combinations of predictor parameters affecting its performance over its design life. In order to maintain good correlation with the field (which considers the loading pattern and the environmental factors), warranty data was analyzed and the predictors were chosen appropriately. Accelerated Life Testing (ALT) method is employed to speed up the process, the stress levels of predictors were selected considering the mechanical and thermal properties of the mount material in addition to the stress level seen by the mount in field. This methodology captures various failure modes of the mount and the interactions of the predictors which are analyzed statistically. The life model created can help understand the behavior of the mount and the expected reliability when put in operation for different applications.