This allows the bit to drill around a central cylinder of rock, which is taken in through the bit and into the core barrel.

这样允许钻头围绕岩石的中心圆柱体钻进，并通过钻头进入取芯桶。

youdao

This allows the bit to drill around a central cylinder of rock, which is taken in through the bit and into the core barrel.

这样允许钻头围绕岩石的中心圆柱体钻进，并通过钻头进入取芯桶。

youdao