如何解决螺纹钢成品孔月牙肋设计中的近似问题

How to Resolve the Approximation Problem in the Design of the Crescent Rib on the Screw-thread Steel Finished Product Passes

螺纹钢成品孔月牙肋的传统设计法不仅繁琐,并且据此而得出的结果有误差。使用这种设计法不能适应国际上对螺纹钢有关外形尺寸的要求。文章采用了无扩张弧的成品孔型,同时相应推导出了简便且无误差的计算方法。

The traditional design method of the crescent rib on the screw-thre ad steel finished product passes is very overelaborate and the results obtained based on it have some errors. The application of this design method doesn't fit in with the international requirements for the external dimension of the screw-thread steel. This paper adopts the finished product pass without expanded arc, and reasons a simple and error-free calculating method.