短語詞組短語bit uniform wear 鉆頭正常磨損bit bearing wear equation 軸承磨速模式bit gage wear 鉆頭直徑磨損bit gauge wear 鉆頭直徑磨小bit excessive wear 鉆頭過度磨損bit t wear 鉆頭磨損drilling -bit wear 刀具磨損 返回 bit wear