Millisecond delay technology of high step and deephole is the first application in China, it offers a realistic method for high step exploitation of middle and small scale limestone mine.
高台段深孔孔内微差爆破技术在我国的首次应用，为中小型石灰石矿山高台段开采提供了切实可行的方法。
2
The method supplys grinding of deep blind hole a economic and reliable technology.
该方法为深盲孔的磨削加工提供了经济可靠的工艺方法。
3
The treatment of collapse body by deephole grouting was described in detail. The construction method and the treatment measures were introduced.