Tie rod is a mechanical part, which provides connection between knuckle and steering rack. Since years outer tie rods are produced with conventional rolling operation methods, but this kind of rolling edge design has more single parts, cost and production cycle time than the pressed design. This disadvantage is pushing the tie rod producer to use pressed design assembly technology. On the other hand, there are also some difficulties such as crack formation during design and production phases for pressed design (e.g. defining pressing parameters and geometry of closing area).
The aim of this study is to determine the optimum housing geometry which fulfills pull out force requirements by optimizing the housing geometry of passenger car outer tie rod (OTR). In this regard, the challenging thing during determination of optimum geometry is to consider not only pull out force requirement, but also max. articulation angle and risk of crack formation have to be taken into account. Because the pull out force of OTR housing is dependent of applied press force during pressing process. It’s directly proportional to press force. At the same time the max. articulation angle and deformation which causes the crack formation on outer surface of OTR housing are inversely proportional to press force and degree of closing process.
For this purpose, different design parameters such as wall thickness and wall height of housing and their effects on the pull out force of outer tie rods (OTR) have been investigated. In pull out force analysis, the pressed outer tie rod housing is taken into consideration. Due to that there is no validated FE Model, firstly the correlation studies are carried out in order to see the deviation between FEA and test results of OTR housing with nominal dimensions. By means of comparing FEA results with test results, the FE model and simulation is validated.
Anahtar Kelimeler: Outer tie rod, pressed design, ball joint, pull out force, finite element analysis
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