特殊用法Broughton countersink1.布劳顿锥坑钻emery countersink1.金刚砂埋头钻machine countersink1.机用锥形锪钻multiple-cutting-edge countersink1.多刃锥口钻rose countersink1.菊花钻snail countersink1.螺旋锥口钻sole cutting edge countersink1.单刃锥口钻