A cutter element for a drill bit. The cutter element has a base portion and an extending portion and the extending portion has either a zero draft or a negative draft with respect to the base portion. The non-positive draft allows more of the borehole bottom to be scraped using fewer cutter elements. The cutter elements having non-positive draft can be either tungsten carbide inserts or steel teeth.
申请公布号
CA2579636(C)
申请公布日期
2009.12.08
申请号
CA19982579636
申请日期
1998.09.03
申请人
SMITH INTERNATIONAL, INC.
发明人
STEINKE, STEPHEN C.;PORTWOOD, GARY R.;GARCIA, GARY E.;MORAN, DAVID P.