Abstract: A system for use in excavating a wellbore that includes a drill string and attached drill bit that has nozzles that are in fluid communication with the drill string. The system receives pressurized slurry of fluid and impactor particles and directs the slurry at a subterranean formation from the nozzles to form the wellbore. Discharge streams are formed from the slurry exiting the nozzles, the discharge streams impact and fracture the formation to remove material. The nozzles are oriented so that the streams excavate in the middle and periphery of the borehole bottom. The nozzles can be oriented to form frusto-conical spray patterns when the bit is rotated, wherein the spray patterns can intersect or overlap.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: A system and method for excavating a subterranean formation, according to which a suspension of liquid and a plurality of impactors are passed between a drill string to a body member for discharge from the body member to remove at least a portion of the formation. The flow of the suspension between the drill string and the body member is controlled by an ultra shearing drilling mud in order to prevent the impactors from settling near the bottom of the formation.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: An excavation system for forming a wellbore through a subterranean formation, the system employing pressurized drilling fluid with impactors mixed therein. The pressurized fluid with impactors is directed to a drill string having a drill bit with nozzles on its lower end. The fluid impactor mixture is discharged from the nozzles and against the formation, wherein the impactors contact, compress, and fracture the formation to excavate through the formation. The system includes an impactor injection system that injects impactors into a stream of pressurized drilling fluid to form the mixture. The injection system operates at substantially the same pressure as the pressurized drilling fluid.

Abstract: A method and system of subterranean excavating that estimates a buoyancy force applied to a downhole excavating system from drilling fluid. The estimated buoyancy force is used to derive a true weight on bit (WOB) at the borehole bottom. The derived realized WOB is compared to a target WOB to obtain a change in WOB. Based on the change in WOB, the excavating system is adjusted so the realized WOB approximates the target WOB. The excavating system adjustment includes applying a compensating force to the string. Compensating forces can be produced by manipulating a block assembly or deploying a thruster device in the string.

Abstract: An injection system and method is described. In several exemplary embodiments, the injection system and method may be a part of, and/or used with, a system and method for excavating a subterranean formation. The system and method include a low density material injection to lower the circulating fluid equivalent circulating density.

Abstract: A particle impact drilling system and method are described. In several exemplary embodiments, the system and method may be a part of, and/or used with, an apparatus or system, methods, to excavate a subterranean formation. The system can including, for example, removing near-borehole damage, casing, window milling, fishing, drilling with casing, under reaming, coring, perforating, effective circulatory density management, assisted annular flow, and directional control. Embodiments of associated systems and methods are also included.

Abstract: A method and system of subterranean excavating that estimates a buoyancy force applied to a downhole excavating system from drilling fluid. The estimated buoyancy force is used to derive a true weight on bit (WOB) at the borehole bottom. The derived realized WOB is compared to a target WOB to obtain a change in WOB. Based on the change in WOB, the excavating system is adjusted so the realized WOB approximates the target WOB. The excavating system adjustment includes applying a compensating force to the string. Compensating forces can be produced by manipulating a block assembly or deploying a thruster device in the string.

Abstract: An excavation system for forming a wellbore through a subterranean formation, the system employing pressurized drilling fluid with impactors mixed therein. The pressurized fluid with impactors is directed to a drill string having a drill bit with nozzles on its lower end. The fluid impactor mixture is discharged from the nozzles and against the formation, wherein the impactors contact, compress, and fracture the formation to excavate through the formation. The system includes an impactor injection system that injects impactors into a stream of pressurized drilling fluid to form the mixture. The injection system operates at substantially the same pressure as the pressurized drilling fluid.

Abstract: An injection system and method is described. In several exemplary embodiments, the injection system and method may be a part of, and/or used with, a system and method for excavating a subterranean formation.