Abstract: The invention is directed to a bi-center drilling tool adapted to fit within and drill through a casing shoe without damage to the surrounding casing. In one embodiment, the tool comprises a bit body having a proximal and a distal end where the distal end defines a pilot bit and an intermediate reamer section, where each the pilot and reamer sections define a bit face including primary and secondary cutting blades and cutting elements disposed on said blades. In this embodiment, the cutting or wear elements disposed on the one or more cutting blades which extend to or are proximate to the pass-through gauge define a selected angle between the line of contact on the cutting or wear elements and the material to be drilled.

Abstract: A bi-center downhole drilling bit is disclosed, which bit includes a body defining proximal and distal ends, where said distal end defines a pilot and a reamer where the reamer defines a first cutting face having a selected diameter “d” and the pilot defines a second cutting face having a selected diameter less than “d”, where each the first and second cutting faces includes upsets defining proximal and distal surfaces where the distal surfaces are provided with cutting elements and the proximal surfaces are provided with one or more gauge pads.

Abstract: The present invention is directed to an improved cutting element for use with rotating downhole tools. More specifically, the present invention is directed to a compact cutter which includes unique configurations for the interface regions between the substrate the abrasive element to promote superior impact resistance and adhesion.

Abstract: A bi-center bit adapted to be consecutively used in casing and in formation without the need of removing the bit from the borehole, the bit comprising a bit body defining a proximal end adapted for connection to a drill string, a distal end and a pass-through gauge, where the distal end defines a pilot bit and an intermediate reamer section, where each the pilot and reamer section define a cutting face. A plurality of cutting or wear elements are situated on cutting blades disposed about the cutting face of the pilot and reamer sections. Cutting or wear elements are disposed on one or more of the blades which extend to or are proximate to the pass-through gauge define an angle between the line of contact on the cutting or wear element and the material to be drilled of between 5-45 degrees.

Abstract: An improved cutting element is disclosed. The cutting element has a disc-shaped body with a front face and a backside. A ring portion formed on the front face extends around a raised central protrusion in formation of a vertical ridge. A plurality of inwardly extending, straight radial slots are formed in the raised central portion and create a plurality of vertical ridge segments. A super-abrasive compound, such as synthetic diamond, is applied to the front face. To aid in stress relief, the ridges have curved corners.

Abstract: Subterranean drill bits and particularly to nozzle features to be incorporated in subterranean bits. In one embodiment, the nozzle assembly of the invention defines a wear resistant structure which extends upstream from the terminus of the transition area. In another embodiment, nozzle assemblies are arranged about the transition area at low angles so as to minimize flow turbulence.

Abstract: A novel cutting element is disclosed as comprised of at an attachment body and a cutting face, where said attachment body is attached to said cutting face via a high temperature braze joint, the attachment body defining a projection and a grooved area, where said grooved area is disposed between the projection and the cutting face, the resultant cutting element providing both enhanced wear characteristics and stability.

Abstract: An improved disc-shaped cutting element including first and second major flat surfaces and a cutting edge, said element comprised of a hard metal substrate defining an irregular interface bonded to a polycrystalline diamond, where said interface includes a plurality of concentric and redial grooves adapted to receive corresponding protrusions formed on the diamond layer so as to enhance wear like and impact resistance.

Abstract: A coring assembly comprising a body securable at its upper end to a mandrel add at its lower end to a core catcher housing, a ball sleeve slidably disposed about said mandrel and moveable between a first and a second position, a ball closure valve disposed in said body and moveable with said mandrel between the first and second position, the combination operable to remotely cut and collect a loosely consolidated core sample.

Abstract: An improved bi-center bit with improved directional stability and wear resistance is disclosed, which bit optimally utilizing a plurality of shaped PDC cutting elements selectively situated about the cutting surfaces of the pilot and the reamer to produce a minimal force imbalance, where further the pilot bit and the reamer are force balanced to further reduce imbalance in the operation of the tool.

Abstract: A drilling tool operational with a rotational drive source for drilling in a subterranean formation where said tool comprises a body defining a face disposed about a longitudinal axis, a plurality of cutting elements fixedly disposed on and projecting from said tool face and spaced apart from one another, and one or more stabilizing elements disposed on the tool face and defining a beveled surface.

Abstract: An improved bi-center with improved directional stability and wear resistance is disclosed, said bit optimally utilizing a plurality of shaped PDC cutting elements selectively situated about the cutting surfaces of the pilot and the reamer to produce a minimal force imbalance, where further said pilot bit and the reamer are force balanced to further reduce imbalance in the operation of the tool.