Soft modelling of the shaping of metal profiles in rapid tube hydroforming technology

Soft modelling of the shaping of metal profiles in rapid tube hydroforming technology

Hanna Sadłowska, Andrzej Kochański

Warsaw University of Technology, Institute of Manufacturing Technologies, Warsaw, Poland.



The paper presents an approach to the impact of process parameters in innovative RTH (Rapid Tube Hydroforming) technology for shaping closed metal profiles in flexible and deformable dies. In order to implement the assumed deformation of the deformed profile, the RTH technology requires the monitoring and control of numerous technological parameters, including geometric, material, and technological variables. The paper proposes a two-stage research procedure considering hard modelling (constitutive) and soft modelling (data-driven). Due to the complexity of the technological process, it was required to develop a numerical finite element method FEM model focused on obtaining the adequate profile deformation measured by the ellipsoidality of the cylindrical profile. Based on the results of the numerical experiments, a preliminary soft mathematical model using ANN was developed. Analysing the soft model results, several statistical hypotheses were made and verified to
investigate the significance of selected process parameters. Thanks to this, it was possible to select the most important process parameters, i.e., the properties of moulding sands used for RTH dies: the angle of internal friction and cohesion.

Cite as:

Sadłowska, H., & Kochański, A. (2022). Soft modelling of the shaping of metal profiles in rapid tube hydroforming technology. Computer Methods in Materials Science, 22(4), 201–210.

Article (PDF):


Rapid tube hydroforming, Manufacturing, Constitutive modelling, Soft modelling, Finite element method, Artificial neural networks


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