The main cause of too small flanged hole end diameter on parts of the Audi car has been found by analysis to be thinning of blank material and rebound.

对奥迪轿车零件翻孔端部直径偏小的分析结果表明，其主要原因是材料变薄及回弹所致。

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"They would go do math for a couple of days and come back with an answer, "LeVey says--to how the grooved dies should look, how much pressure should be applied to the blank, and what the diameter of the blank should be.

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