Development of Method of Sheet Metal Molding to Increase Bushing and Ball Joint Pull-Out Forces

Today, control arms, which are part of the suspension system for passenger vehicles, are recognized as important load-carrying elements of the system. In the constantly changing and developing automobile world, it is expected that the equipment will successfully pass the necessary tests simulating conditions of use.  In the suspension system, the bushing pull out test on the wishbone and control arms, as well as the empty and full weight of the vehicle, it is unacceptable that it comes out below the critical load determined because it is subjected to more load on extreme conditions.

In this article, a new molding method was used to minimize the inefficient contact surface of the bushing and ball-joint mating heights of the control arms, and an increase in contact surface and exit loads was achieved by increasing the contact surface. Increasing the contact surface was first performed by analyzing it using a mathematical model. As a result of the results obtained, there was an increase in pull-out forces. Based on the analyses, a new molding method was developed to increase the mating contact surface. The samples obtained by this developed method were subjected to pull-out force test. It was seen that an increase of about 50% was achieved in the pull-out forces compared to the classical molding method. Consistency was observed when the obtained samples and the results of the mathematical model analysis were compared.