A New Approach for Quantitative Evaluation of Bending Components

Abstract:

During the bending of tubes, specific geometric deviations from the desired shape geometry occur. These deformations comprise cross-sectional deformation, wall-thinning of the outer arc and wall-thickening of the inner arc. During the bending of parts with small bend factors, geometric deviations on the inner arc in form of waves and wrinkles may arise as other typical quality criteria. A quantitative evaluation of those deviations has yet to be defined. Currently, only an instruction for measuring the height of the wrinkles at the inner arc according to DIN EN 13480-4 is known. In this standard, only the two highest wrinkles and the valley in between are included. The characteristics of the wrinkle, especially the flank angle and the rise of deformation are disregarded, although they are responsible for the failure of the bent part. Tool damages can also occur. A development of an evaluation factor to assess deformations in the bow area for bent parts is presented in this paper. In addition, it will be possible to quantify geometric deviations in the bow area. By using the newly developed evaluation factor for geometrical deformations in the bow area, the determination of the quality of the bent part should become more reproducible.

• Periodical: Key Engineering Materials (Volumes 622-623)
• Pages: 1095-1102
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.622-623.1095
• Online since: September 2014
• Authors: Bernd Engel, Christopher Kuhnhen*, Christian Mathes, Christopher Heftrich, Peter Frohn, Sebastian Groth
• Keywords: Bending, Forming, Gauging, Measuring, Production Process, Quality Management

References

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