To solve the problem of well bore cleaning during air and mistdrilling, the test device is the key equipment and essential means.
解决空气雾化钻井井眼净化问题，试验架是关键装置、基础设备和必要手段。
2
In air and mistdrilling, annular carries are the typical of gas, liquid and solid multiphase flow, and its mechanism and principles are very complicated.
在空气雾化钻井中，井眼环空携岩流动是一种典型的气、液、固多相流动，其机理和规律十分复杂。
3
The problem in those days was somewhat resolved with an addition of a nozzle to the drill which sprayed a mist of water, turning dust raised by drilling into mud, but this inhibited mining work.