Interpretation of Laboratory Tests on Universal Joints

The Cardan universal joint is widely used in highway and off-highway vehicles to transmit power for propulsion and accessories. In spite of its wide use, the analysis of driveline failures is complex because the failure modes are inter-related and the time required for wear failures to develop allows much evidence of the primary failure mode to be obscured.

This paper presents a description of the basic failure modes that are common to Cardan universal joints and the relation between these failure modes and the laboratory tests that are used to investigate their effect on service life. Methods of analyzing the data generated in laboratory tests are also discussed. Finally, a comprehensive example is presented to show the accumulation of information that can be obtained from a complete test program.