Use of FEA and design of experiments to establish design guidelines for simple hydroformed parts

We present models to predict the protrusion height of `Tee-shaped' hydroformed parts, both because this information is of direct relevance to engineers attempting to build such parts and also to illustrate an advantageous process for developing design guidelines for tube hydroforming (THF) in general. A newly proposed design of experiments technique, Low Cost Response Surface Method (LCRSM), was utilized to facilitate the economical prediction and optimization of this height as a function of geometrical parameters subject to thinning of the wall thickness at the protrusion region. The same methodology is also proposed for the economical investigation of other geometries and conditions. As a result of this investigation, not only were known and expected trends of effect of parameters verified, but also numerical values within a practical range of parameters at certain conditions were obtained. In addition, interactions between factors were also revealed as predicted. Moreover, this information was gained from a substantially reduced number of finite element analysis (FEA) simulations via LCRSM compared to standard response surface method (RSM) or factorial techniques, avoiding costly physical experimentation.