Assertion: annular diamond impregnated drill bit | /r/AtLocation | the end of hollow drill rods
Facets:
Source sentences:
text: Diamond core drilling (exploration diamond drilling) uses an annular diamond-impregnated drill bit attached to the end of hollow drill rods to cut a cylindrical core of solid rock.
text: Diamond drilling utilizes an annular diamond-impregnated drill bit attached to the end of hollow drill rods to cut a cylindrical core of solid rock.