n.推削；拉削；拉孔
動(dòng)詞broach的現(xiàn)在分詞形式.
A new simple method for broaching spline holes with a common machine, which has enlarged Screwpitch, is introduced. 介紹了一種在有增大螺距的普通車床上拉削花鍵孔的新方法。
