A drill bit configured for boring holes or wells into the earth include a plurality of blades configured with a recessed center such that the blades cut a core therebetween. Cutting elements in the recessed center are configured to cut and remove the core. The recessed center has a first diameter at a height from the cutting elements in the recessed center and a second diameter smaller than the first diameter such that the confining stress on the core is relieved prior to being cut by the cutting elements in the recessed center.
申请公布号
WO2011057303(A3)
申请公布日期
2011.07.28
申请号
WO2010US56089
申请日期
2010.11.09
申请人
NEWTECH DRILLING PRODUCTS, LLC.;JONES, MARK, L.;JOHNSON, KYLE, E.