复杂异型零件小直径螺纹优质高效加工工艺研究与应用

复杂异型壳体类零件广泛应用于航空发动机控制附件，此类零件表面分布有大量小直径螺纹孔，螺纹孔加工是影响整个壳体生产加工效率和精度的核心工序。该类零件现有的加工工艺存在一致性差、加工效率低、专用夹具多、铣螺纹时易出现正锥现象等缺点。针对上述问题，提出并设计专用螺纹铣刀进行加工，通过宏程序编程解决刀具刃部缩短带来的编程问题，采用刃部长度为1~3 个螺距的专用螺纹铣刀，同种刀具即可实现相同螺距不同规格的螺纹孔加工。通过对两个批次的零件进行实际加工验证，结果表明：工艺优化方案可使小直径螺纹孔加工质量及效率得到显著提升。

Research and application of high quality and high efficiency machining technology for shell small aperture thread

Shell parts are widely used in aeroengine control accessories. A large number of small aperture threads are distributed on the surface of these parts. In the whole process of shell production and processing, thread processing is the core process that affects the processing efficiency and accuracy The existing thread processing technology is as follows: first, roughly milling the shell thread by using the NC machining center and then conducting manual tapping. This processing technology has the disadvantages of poor consistency, low processing efficiency, and many special fixtures. At the meantime, the phenomenon of positive cone is easy to appear when milling the thread. In view of these problems, this paper proposes and designs a special thread milling method for processing, which solves the programming problem caused by the shortening of the cutting edge through macro programming. Therefore, the thread can be processed together with the bottom hole, which reduces the manual tapping process and various threads with the same pitch and different specifications can be processed by one cutter. Finally, two batches of parts are verified bt experimental process, and the experimental results are analyzed to verify the reliability of the scheme of processing optimization.