rock drill bit

基本解释

Abrasive particle in the circulation medium from hard rock and drill bit cut the element.
循環介質中的磨料粒子（來自硬巖、鑽頭），對元件進行切割；
Our research demonstrate that the drill string vibration is forced vibration, it needs to consider the rock-drill bit-drill string-swivel as the "drill string vibration system";
研究認爲鑽柱振動是一受迫振動問題，需要將井底巖石-鑽頭-鑽柱-水龍頭作爲一個“鑽柱振動系統”來對待；
www.cea.gov.cn
In order to solve the problem of low efficiency drilling in hard and compact rock with diamond drill bit, efforts were made to manufacture electroplated weakly-bonded diamond bit.
爲了解決電鍍金剛石鑽頭鑽進堅硬致密巖石時傚低的問題，進行了電鍍弱包鑲金剛石鑽頭的研究。

But for shale gas, once the drill reaches the shale rock underground, the drill bit is turned horizontally to bore a well that stretches through the natural gas producing shale.
FORBES: China Closer To Joining Shale Gas Fracking Craze