Unformatted text preview: bend models. Such models apply geometric approximations of the bend features to be produced to Factors Influencing Dimensional Accuracy of Bent Parts 343 provide the bend allowance for each bend line, depending on the characteristics of the bend features, such as bend angle, inner radius, sheet thickness, and material properties. Since there are always discrepancies between the bend model and the actual material behaviour, there exists an error in the calculation of the unfolding. The flat pattern calculated is then cut out from a sheet by a cutting process such as shearing, punching, nibbling, or laser cutting, which can provide various quality of cutting. The precision of the processes selected for workpiece preparation directly affects the dimensional accuracy of the workpiece. After being prepared, the workpiece is positioned on top of the die by placing one of its edges or flanges against a backgauge of the machine before being bent linearly by a punch penetrating into the die cavity. In this phase, the positioning accuracy is determined by factors such...
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This note was uploaded on 08/03/2010 for the course DD 1234 taught by Professor Zczxc during the Spring '10 term at Magnolia Bible.
- Spring '10
- The Land