对于环形锻件在自由锻设备上生产,一般常采用平马杠扩孔,而带有内凸缘的齿圈(如图1)也按老工艺锻造,即将坯料冲孔后,在三吨自由锻锤上用平马杠扩孔呈圆环形(如图2),其锻件重量近达215公斤,这样不仅费料,而且内孔加工余量太大。我厂锻工同志针对上 Ring forging in the free forging equipment production, generally used flat mandrel reaming, and with the inner flange of the ring gear (Figure 1) is also forged according to the old process, about to punching the blank, three tons of free forging Hammer with the flat mandibular reaming was circular (Figure 2), the forging weight of nearly 215 kilograms, so that not only the cost of material, but the machining allowance is too large hole. Our factory forgings for comrades