多规格方钻杆（四方）螺纹加工辅助夹具的设计

Aided Fixture Design for Thread Cutting Process of Multi-sized Square Kelly

方钻杆是组成钻柱的主要部件之一，它承受着钻柱的全部重量，是钻柱运转的驱动部件。由于它的结构特殊性，导致了它的螺纹维修加工需要一种合适的专用夹具来辅助加工，否则会严重影响加工质量和加工设备的使用寿命，对周围环境也造成不良影响。针对这些问题对夹具进行了设计，从而降低成本、提高产品的加工质量以及生产率。

Kelly is an important part of drill strings.It subjected to all weight of drill strings. So the thread cutting of kelly is very important. Because of the specific structure of kelly,it needs a proper aided fixture to the thread cutting, otherwise it will impact on product quality and working life of the equipment also on environment. For those questions we designed the fixture,in order to reduce production cost and improve product quality.