Patents Examined by Daivd J Bagnell
  • Dual-edge working surfaces for polycrystalline diamond cutting elements
    Patent number: 7568534
    Abstract: A polycrystalline diamond cutting element for earth boring drill bits presents regions of different abrasion resistance to the earthen formation when in operation. The cutting element has an end working surface and a region which is substantially free of catalyzing material, forming a layer. In operation, this layer wears at a different rate than the underlying material causing a pair of protruding lips to form. The end working surface may be substantially planar or frusto-conical in form.
    Type: Grant
    Filed: February 26, 2008
    Date of Patent: August 4, 2009
    Assignee: ReedHycalog UK Limited
    Inventors: Nigel Dennis Griffin, Peter Raymond Hughes, Andrew Bell