The flow function method was applied to the process of screw rolling balls in the paper. The computing formulas of rolling power and force were given. Finally the computing example was presented.

采用流函数方法，对螺旋孔型斜轧过程进行了分析，得到了轧制过程力能参数的计算公式，并进行了实例计算和比较。

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Manipulating the shape of the threads using this method, called thread-rolling, was thought to be impossible because it would be too hard to control the structure of the screw if metal oozed into odd shapes.

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