Abstract: Rock strength is estimated during drilling using a rate of penetration model or a modified mechanical specific energy models. The rock strength estimate can be used in conducting further drilling, for example by a drilling system. Drilling parameters may be altered as a result of determining rock strength, for example to avoid undesirable trending fractures, such as extensive vertical fractures.

Abstract: There is described a drilling fluid for wellbore strengthening having nanoparticles and granular particles. In one aspect described herein, the drilling fluid is an invert emulsion based fluid. In a further aspect, the nanoparticles are iron hydroxide or calcium carbonate, and in a further aspect from about 1 to 30 nm in size. In one aspect described herein, the granular particles are graphite or calcium carbonate and in a further aspect, up to 250 ?m in size. The nanoparticles and granular particles plug fractures in the wellbore to strengthen the wellbore.

Abstract: A use of nanoparticles in a well fluid for improved lubricity is disclosed herein. The nanoparticles are present in the well fluid in low amounts below 5 wt %. The nanoparticles may be formed ex situ and added to the fluid or in situ in the fluid. In one aspect, the well fluid is a drilling fluid. In a further aspect, the well fluid is an invert emulsion based fluid or an aqueous based fluid.

Abstract: A use of nanoparticles in a well fluid for improved lubricity is disclosed herein. The nanoparticles are present in the well fluid in low amounts below 5 wt %. The nanoparticles may be formed ex situ and added to the fluid or in situ in the fluid. In one aspect, the well fluid is a drilling fluid. In a further aspect, the well fluid is an invert emulsion based fluid or an aqueous based fluid.

Abstract: A use of nanoparticles in a well fluid for improved lubricity is disclosed herein. The nanoparticles are present in the well fluid in low amounts below 5 wt %. The nanoparticles may be formed ex situ and added to the fluid or in situ in the fluid. In one aspect, the well fluid is a drilling fluid. In a further aspect, the well fluid is an invert emulsion based fluid or an aqueous based fluid.

Abstract: The present invention is directed to a well fluid, and in particular a drilling fluid having low amounts of nanoparticles which act as fluid loss material for reducing fluid loss in an underground formation. The fluid is a nanoparticle-containing well fluid comprising a base fluid and about 5 wt % or less nanoparticles, for preventing or reducing fluid loss to an underground formation, wherein the well fluid is a drilling fluid, kill fluid, completion fluid, or pre-stimulation fluid. The invention also includes in situ and ex situ methods of forming the nanoparticles.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending through the drill bit head to the cutting face; a flow interrupter within the drill bit head and positioned to interrupt flow of fluid through the flow passage; and a power section connected to drive the flow interrupter and cause, in operation, variable flow of fluid through the flow passage. A method of drilling is also disclosed comprising: flowing fluid through a flow passage extending through a drill bit head to a cutting face of the drill bit head, the cutting face having one or more fixed cutting elements; and driving a flow interrupter within the drill bit head with a power section to interrupt the flow of fluid through the flow passage and cause variable flow of fluid through the flow passage.

Abstract: A use of nanoparticles in a well fluid for improved lubricity is disclosed herein. The nanoparticles are present in the well fluid in low amounts below 5 wt %. The nanoparticles may be formed ex situ and added to the fluid or in situ in the fluid. In one aspect, the well fluid is a drilling fluid. In a further aspect, the well fluid is an invert emulsion based fluid or an aqueous based fluid.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending through the drill bit head to the cutting face; a flow interrupter within the drill bit head and positioned to interrupt flow of fluid through the flow passage; and a power section connected to drive the flow interrupter and cause, in operation, variable flow of fluid through the flow passage. A method of drilling is also disclosed comprising: flowing fluid through a flow passage extending through a drill bit head to a cutting face of the drill bit head, the cutting face having one or more fixed cutting elements; and driving a flow interrupter within the drill bit head with a power section to interrupt the flow of fluid through the flow passage and cause variable flow of fluid through the flow passage.

Abstract: There is described a drilling fluid for wellbore strengthening having nanoparticles and granular particles. In one aspect described herein, the drilling fluid is an invert emulsion based fluid. In a further aspect, the nanoparticles are iron hydroxide or calcium carbonate, and in a further aspect from about 1 to 30 nm in size. In one aspect described herein, the granular particles are graphite or calcium carbonate and in a further aspect, up to 250 ?m in size. The nanoparticles and granular particles plug fractures in the wellbore to strengthen the wellbore.

Abstract: Rock strength is estimated during drilling using a rate of penetration model or a modified mechanical specific energy models. The rock strength estimate can be used in conducting further drilling, for example by a drilling system. Drilling parameters may be altered as a result of determining rock strength, for example to avoid undesirable trending fractures, such as extensive vertical fractures.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending from the center towards the gage of the bit which has been designed to increase the velocity across the cutting elements.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending through the drill bit head to the cutting face; a flow interrupter within the drill bit head and positioned to interrupt flow of fluid through the flow passage; and a power section connected to drive the flow interrupter and cause, in operation, variable flow of fluid through the flow passage. A method of drilling is also disclosed comprising: flowing fluid through a flow passage extending through a drill bit head to a cutting face of the drill bit head, the cutting face having one or more fixed cutting elements; and driving a flow interrupter within the drill bit head with a power section to interrupt the flow of fluid through the flow passage and cause variable flow of fluid through the flow passage.

Abstract: An autodriller provides an automatic self calibration system to predict both axial and rotational friction coefficients from the surface measurements such as hookload and surface torque while a drill bit is off bottom. The friction coefficients are used to calculate the friction forces between drillstring and the wellbore while the bit is on bottom during drilling operation to estimate downhole weight on the bit and bit torque, and use the estimates to alter the drilling process.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending from the center towards the gage of the bit which has been designed to increase the velocity across the cutting elements.

Abstract: A drill bit comprises: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending through the drill bit head to the cutting face; a flow interrupter within the drill bit head and positioned to interrupt flow of fluid through the flow passage; and a power section connected to drive the flow interrupter and cause, in operation, variable flow of fluid through the flow passage. A method of drilling comprises: flowing fluid through a flow passage extending through a drill bit head to a cutting face of the drill bit head, the cutting face having one or more fixed cutting elements; and driving a flow interrupter within the drill bit head with a power section to interrupt the flow of fluid through the flow passage and cause variable flow of fluid through the flow passage.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending from the center towards the gage of the bit which has been designed to increase the velocity across the cutting elements.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending from the center towards the gage of the bit which has been designed to increase the velocity across the cutting elements.

Abstract: A drill bit is disclosed, comprising: a drill bit head having a cutting face with one or more fixed cutting elements; a flow passage extending through the drill bit head to the cutting face; a flow interrupter within the drill bit head and positioned to interrupt flow of fluid through the flow passage; and a power section connected to drive the flow interrupter and cause, in operation, variable flow of fluid through the flow passage. A method of drilling is also disclosed comprising: flowing fluid through a flow passage extending through a drill bit head to a cutting face of the drill bit head, the cutting face having one or more fixed cutting elements; and driving a flow interrupter within the drill bit head with a power section to interrupt the flow of fluid through the flow passage and cause variable flow of fluid through the flow passage.