短语词组短语Hollow rock drill steel 凿岩钎杆用中空钢;中空钢Hollow -Drill Steel 空心钻杆;空心钻钢hollow rock drill steel rolling 中空钢轧制hollow drill steel bar 中空钻杆钢筋hollow drill steel steachdard 中空钻杆钢筋 返回 hollow drill steel