The research and application for improving the coarse pitch numerical control program

By the method of feeding hierarchically several times and applying the Calculation and circulatory function of NC system, we can changing the value of the variable and complete the process for different types of thread well. Also, the coarse pitch´s shortcomings, including the special shapes of the section, the poor chip removal when processing , the severe vibration when cutting, unable to use traditional means to turn the thread, and so on, is avoided.