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Centered coined-bead technique for precise U-bent part fabrication

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Abstract

Recently, during the fabrication of U-bent parts, increasing levels of precision have been required not only for the bend angle of the part but also for the bend radius and the flatness of its bottom surface. The conventional coined-bead technique is therefore unlikely to be applied to achieve these requirements. As an innovative variation of the coined-bead technique, the centered coined-bead technique is proposed and investigated in this study. The finite element method (FEM) was used to clearly identify the parameters of interest based on a stress distribution analysis. The results show that the centered coined-bead formation could be applied to produce a balance between the bending and reversed bending characteristics and to eliminate these characteristics in the bottom surface. Therefore, a precise bend angle and bend radius and a flat bottom surface could be achieved. The effects of the coined-bead geometry and its positioning are also examined and clearly identified, and laboratory experiments were carried out to validate the FEM simulation results. Each U-bent part could be fabricated with a precise bend angle and bend radius and a flat bottom surface using the centered coined-bead technique. The recommended coined-bead geometry and positioning are also reported.

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Authors and Affiliations

  1. Department of Tool and Materials Engineering, King Mongkut’s University of Technology Thonburi, 126 Pracha Uthit Rd., Bang Mod, Thung Khru, Bangkok, 10140, Thailand

    Wiriyakorn Phanitwong & Sutasn Thipprakmas

Authors
  1. Wiriyakorn Phanitwong
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  2. Sutasn Thipprakmas
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Correspondence to Sutasn Thipprakmas.

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Phanitwong, W., Thipprakmas, S. Centered coined-bead technique for precise U-bent part fabrication. Int J Adv Manuf Technol 84, 2139–2150 (2016). https://doi.org/10.1007/s00170-015-7858-8

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  • DOI: https://doi.org/10.1007/s00170-015-7858-8

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