Rotary Drill Bit with Improved Steerability and Reduced Wear

A rotary drill bit operable to form a wellbore comprising:

• a bit body having one end operable for releasable engagement with a drill string;
• a bit rotational axis extending through the bit body;
• a bit face profile defined in part by a plurality of blades disposed on exterior portions of the bit body;
• each blade having a respective gage pad;
• a plurality of cutting elements disposed on exterior portions of each blade;
• a first cutting element disposed on each blade at a respective first distance from the bit rotational axis;
• a last cutting element disposed on each blade proximate the respective gage pad, each last cutting element disposed on each blade at approximately the same height measured parallel to the bit rotational axis;
• the other cutting elements disposed on exterior portions of each blade between the associated first cutting element and the associated last cutting element;
• an open space disposed on each blade between adjacent cutting elements;
• and
• the last cutting element on each blade cooperating with the respective gage pad, during rotation of the drill bit, to form the wellbore with a substantially uniform inside diameter with substantially no uncut formation material remaining between the last cutting element and the respective gage pad.

A rotary drill bit having a bit body with a plurality of blades disposed on exterior portions of the bit body comprising:

• one end of the bit body operable for attachment to a drill string;
• a bit rotational axis extending through the bit body;
• each blade having an associated gage pad;
• a plurality of cutting elements disposed on exterior portions of each blade;
• a respective first cutting element disposed on each blade at a respective first radial distance from the bit rotational axis;
• a respective last cutting element disposed on each blade close to the associated gage pad;
• the other cutting elements disposed on exterior portions of each blade between the respective first cutting element and the respective last cutting element;
• the cutting elements on each blade spaced from each other to form a respective gap between adjacent cutting elements;
• each cutting element operable to form a kerf in adjacent portions of a downhole formation in response to rotation of the drill bit;
• and
• the respective last cutting element of each blade operable to form a kerf with an overlap between approximately eighty percent (80%) and one hundred percent (100%) of the kerfs formed by the respective last cutting elements of the other blades.

A rotary drill bit operable to form a wellbore comprising:

• a bit body having one end operable to engage a drill string;
• a bit rotational axis extending through the bit body;
• a bit face profile defined in part by a plurality of blades disposed on exterior portions of the bit body;
• each blade having an associated gage pad;
• a plurality of cutting elements disposed on exterior portions of each blade;
• a respective first cutting element disposed on each blade at a respective first radial distance from the bit rotational axis;
• a respective last cutting element disposed on each blade immediately adjacent to the associated gage pad;
• the other cutting elements disposed on exterior portions of each blade between the respective first cutting element and the respective last cutting element;
• and
• the cutting elements on each blade spaced from each other to form a respective open space between adjacent cutting elements.

A method of forming a rotary drill bit operable to drill a wellbore in a downhole formation comprising:

• forming a bit body having one end operable for connection to a drill string;
• forming a plurality of a blades disposed on exterior portions of the bit body;
• placing a respective first cutting element on an exterior portion of each blade at a respective location relative to a bit rotational axis;
• placing a respective last cutting element on exterior portions of each blade adjacent to a downhole edge of an associated gage pad such that each last cutting element is disposed on each blade at approximately the same height with respect to the bit rotational axis;
• and
• placing the remaining cutting elements on exterior portions of each blade between the respective first cutting element and the respective last cutting element.

A rotary drill bit operable to form a wellbore in a downhole formation comprising:

• a bit body having one end operable for connection to a drill string;
• a bit rotational axis extending through the bit body;
• a bit face profile defined in part by a plurality of blades disposed on exterior portions of the bit body;
• each blade having an associated gage pad, each gage pad disposed at approximately the same height as measured along the bit rotational axis;
• a plurality of cutting elements disposed on exterior portions of each blade;
• a respective first cutting element disposed on each blade at a respective first radial distance from the bit rotational axis;
• a respective last cutting element disposed on each blade adjacent to a downhole edge of the associated gage pad;
• the other cutting elements disposed on exterior portions of each blade between the respective first cutting element and the respective last cutting element;
• a respective gap formed between adjacent cutting elements;
• and
• the last cutting element of each blade at least partially overlapping with the last cutting element on each adjacent blade to form an active gage for directional drilling of a wellbore.