Design and Production of a New Smaller Diameter Axial Bearing Subjected to High Wear Loads

Abstract

In the steering system of a passenger car, one of the essential components is the tie rod, and the sub-assembly component is the inner tie rod, which is subject to static and dynamic bearing loads. These bearing loads are the key points to ensure the inner tie rod's performance and total lifetime. A significant drop in the inner tie rod's performance can cause uncomfortable driving conditions and noise during driving. Most of the designs are developed over-safe with bigger ball sizes to fulfill the defined requirements. On the other hand, over-safe design can cause higher prices. In this study, a new small diameter axial bearing system is developed subjected to high wear loads on the inner tie rod. Three design parameters are considered: press force, tempering method, and tempering temperature. A smaller ball diameter design is created during the development phase. After the manufacturing, the inner tie rods are tested concerning the wear test and setting behavior under the maximum loading test. Results have been compared with a bigger ball size design. By changing the production and assembly parameters, optimum assembly conditions have been defined. Functional measurements before and after testing have validated the new smaller ball diameter design for serial usage.