大直径大导程多头梯形内螺纹的数控加工

介绍了采用数控化改造的CQ5250立车设备,加工大直径零件上的大导程多头梯形左旋内螺纹的加工方法。阐述了螺纹车刀的选用、螺纹分度法的确定、螺纹加工工艺的确定、螺纹的数控加工程序，以及叶轮硬化后使用轴头螺纹规修螺纹的方法。利用该数控加工方法加工叶轮上的螺纹，既能够保证螺纹的加工精度，又可以减少刀具重磨和重定位次数，缩短辅助时间，提高生产效率。

The Research of the Numerical Control Machining in Large Diameter Multiple-Internal Screw Thread

The machining technique is recommended about machining the steep-lead multiple trapeziform left-hand internal screw thread in large diameter part using numerical control reformed CQ5250 vertical lathe. It is expatiated that threading tool chosen, the method of screw thread indexing, the method of screw thread machining, the machining procedure of screw thread, and the method of repairing screw-thread using gudgeon screw-thread gauge inharden impeller. The method not only guarantees the machining precision, but also reduces the times of the cutter regrinding and reorientation, reduces accessorial time, and improves production efficiency.