Front Spring Development & Validation for Medium Duty Truck 2023-36-0368

Improvements in component/system design is a daily challenge these days, always looking for high performance, reduced mass and low costs. The source for the best fit between these factors, coupled with adequate durability performance, is crucial to the success of a given product and this is what motivates engineering teams around the world. The demand for efficient projects with short deadlines for validation and certification is huge and simulation tools focused on accelerated durability and virtual validation are increasingly being used. When developing a new spring for commercial vehicles, lessons learned from the actual loads applied to the suspension are the “key” to a successful project. The loads/stresses from the ground (vertical loads, lateral loads, longitudinal and braking loads) are quite high and, consequently, relevant to the proper definition of the design of the suspension components. The objective of this work is to describe the main development activities faced during a completely new spring development, passing through the design, considering all the limit conditions related to the raw material, lamination process, tempering, rhinestone/shot peening, prefixing and, finally, the load conditions for an adequate fatigue life. The methodology adopted for the definitions of load and fatigue in a bench test is part of this document and, in the end, all iteration results, such as correlation with the application, the MBS and FEA models to be fed again until final validation in a vehicle. This document is a joint development made in partnership between Thyssen Krupp Springs and Stabilizer Bars, Dana Corporation and Volkswagen Truck & Bus (VWTB).