FIXED CUTTER DRILL BIT WITH CORE FRAGMENTATION FEATURE

摘要

A drill bit has a plurality of blades that include a coring blade, a plurality of flow courses that include an evacuation slot disposed between the plurality of blades, and a conical insert disposed on or proximate a bit centerline of the drill bit. Coring blade includes a first cutting element disposed at a first radial position from the bit centerline. Also, coring blade includes a substantially vertical surface and an angled surface. During drilling, first cutting element cuts formation to generate a core sample fragment at bit centerline. Core sample fragment is then broken away from formation using angled surface or conical insert after core sample fragment reaches a certain length. Core sample fragment then exits drill bit via an evacuation slot, from where core sample fragment is transported via an annulus to the surface of formation for testing and analysis.