Abstract: Provided is a downhole vibrating tool comprising an interconnected power section, axial shock assembly and lateral vibration assembly wherein the power section comprising a rotor and a stator, the rotor comprising a plurality of lobes and the stator comprising a second plurality of recesses adapted to receive the plurality of lobes, the number of recesses greater than the number of lobes; the axial shock assembly comprising a valve assembly, the axial shock assembly adapted to vary fluid flow therethrough; and the lateral vibration assembly comprising an eccentric mass; wherein the power section, the axial shock assembly and the lateral vibration assembly are aligned linearly.

Abstract: Provided is a downhole vibrating tool comprising an interconnected power section, axial shock assembly and lateral vibration assembly wherein the power section comprising a rotor and a stator, the rotor comprising a plurality of lobes and the stator comprising a second plurality of recesses adapted to receive the plurality of lobes, the number of recesses greater than the number of lobes; the axial shock assembly comprising a valve assembly, the axial shock assembly adapted to vary fluid flow therethrough; and the lateral vibration assembly comprising an eccentric mass; wherein the power section, the axial shock assembly and the lateral vibration assembly are aligned linearly.

Abstract: Provided is a downhole vibrating tool comprising an interconnected power section, axial shock assembly and lateral vibration assembly wherein the power section comprising a rotor and a stator, the rotor comprising a plurality of lobes and the stator comprising a second plurality of recesses adapted to receive the plurality of lobes, the number of recesses greater than the number of lobes; the axial shock assembly comprising a valve assembly, the axial shock assembly adapted to vary fluid flow therethrough; and the lateral vibration assembly comprising an eccentric mass; wherein the power section, the axial shock assembly and the lateral vibration assembly are aligned linearly.

Abstract: Earth-boring tools include wear-resistant materials disposed in at least one recess formed in an exterior surface of a body thereof. Exposed surfaces of the wear-resistant material are substantially level with exterior surfaces of the body adjacent the wear-resistant material. In some embodiments, recesses may be formed in formation-engaging surfaces of blades of earth-boring rotary tools, adjacent one or more inserts secured to bodies of earth-boring tools, or adjacent one or more cutting elements secured to bodies of earth-boring tools. Methods of forming earth-boring tools include filling one or more recesses formed in an exterior surface of a body with wear-resistant material and causing exposed surfaces of the wear-resistant material to be substantially level with the exterior surface of the body.

Abstract: A method for evaluating existing drill bits and drill bit designs includes measuring several desired characteristics of a bit, including the wear experienced in drilling a formation, such as an actual formation or a simulated formation or a laboratory test fixture. A computer model may be used to evaluate the work-force and/or the sliding-wear rates that cutting elements of the bit experience as compared with the rate-of-penetration and/or durability of the bit. This information may be used to design a new drill bit, which may involve modification of the cutting elements (e.g., moving the location, volume (size and shape) or number of cutting elements from areas of the bit that receive lower work-force and sliding-wear rates to those areas that experience relatively greater work-force and sliding wear-rates. This may permit the cutting elements to be oriented more aggressively relative to a formation to be drilled.

Abstract: A rotary drilling apparatus and method for drilling subterranean formations, including a body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation, so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per rotation of the drilling apparatus, as well as to control the amount of torque experienced by the drilling apparatus and an optionally associated bottomhole assembly regardless of the effective weight-on-bit are all disclosed. The exterior of the drilling apparatus may include a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute an additional weight applied to the drilling apparatus against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: A rotary drag bit and method for drilling subterranean formations, including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation, so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit are all disclosed. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute an additional weight applied to the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: In a protective circuit for a field-effect transistor which has at least drain-, source- and gate-terminals and is operated as a power switch, overloading of the FET is prevented in case of a power supply voltage of inverted polarity in that the switching voltage is able to be supplied to the gate terminal as a driving voltage via a charge pump. The charge pump is powered via a suitable circuit (e.g., a Graetz bridge rectifier) independently of the polarity of the applied power supply voltage. In case of incorrect polarity of the power supply voltage, the charge pump is driven to output a driving voltage via a suitable circuit (e.g., a diode connected to the base terminal).