INVESTIGATION OF THE EFFECT OF BENDING PROCESS ON FATIGUE LIFE AND MECHANICAL STRENGTH OF HEAVY COMMERCIAL VEHICLE DRAG LINKS

Abstract

In heavy commercial vehicles, the part that enables the wheels to turn left and right by transferring the movement from the steering box to the wheel via the pitman is called the steering drag link. In order to obtain the desired form in the production of bended drag links, the pipe material is subjected to bending process from certain points by various methods. During this bending process, plastic deformation occurs in the material. In this study, the effect of plastic deformation in tie rod bending on the life of the drag link was investigated. The amount of plastic deformation in the bending region was determined as %12 by performing tie rod bending simulation in a Finite Element Analysis (FEA) software. The fatigue behavior of the %6 and %12 pre-strained material was determined and compared with the fatigue behavior of the undeformed material. Fatigue analyses were carried out in the finite element environment by modeling the drag link as Functionally Graded Material (FGM). In addition, the drag link physical fatigue tests were also carried out and the numerical and experimental results were compared. It was observed that the results of the drag link fatigue analysis modeled as FGM were closer to the experimental values.

Keywords

• Drag link
• Pipe Bending
• Plastic deformation
• Steering system
• Fatigue

References

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