A method for lateral drilling into a subterranean formation whereby a shoe is positioned in a well casing, the shoe defining a passageway extending from an upper opening in the shoe through the shoe to a side opening in the shoe. A rod and casing mill assembly are inserted into the well casing and through the passageway in the shoe until a casing mill end of the casing mill assembly substantially abuts the well casing. The rod and casing mill assembly are rotated until the casing mill end substantially forms a perforation in the well casing. An internally rotating nozzle is attached to an end of a hose and is pushed through the passageway and the perforation into the subterranean formation, and fluid is ejected from tangential jets into the subterranean formation for impinging upon and eroding the subterranean formation.

A method for lateral drilling into a subterranean formation whereby a shoe is positioned in a well casing, the shoe defining a passageway extending from an upper opening in the shoe through the shoe to a side opening in the shoe. A rod and casing mill assembly are inserted into the well casing and through the passageway in the shoe until a casing mill end of the casing mill assembly substantially abuts the well casing. The rod and casing mill assembly are rotated until the casing mill end substantially forms a perforation in the well casing. An internally rotating nozzle is attached to an end of a hose and is pushed through the passageway and the perforation into the subterranean formation, and fluid is ejected from tangential jets into the subterranean formation for impinging upon and eroding the subterranean formation.

A deep low-permeability gassy seam drilling-slitting-sealing-fracturing drilling device includes a drilling control system, a high-pressure water power system, a water pressure grading control system and a fracturing and sealing control system. The drilling control system adjusts a drilling direction a water supply pressure of the drill rod, the high-pressure water power system supplies high-pressure water with different pressures to the device, and the water pressure grading control system ensures that a water pressure for flushing drill cuttings is less than 5 MPa, a water pressure for slitting in a direction perpendicular to a length of the drill rod is 25-35 MPa, a water pressure for sealing with a borehole sealing capsule is 35-40 MPa, and a water pressure for further pressure relief and permeability increasing of a coal seam is 40-50 MPa. The fracturing and sealing control system controls borehole sealing and hydrofracturing operations.

A drill bit includes a bit body with high and low fluid pressure bodies. The low-pressure bit body includes a fixed cutting structure, and the high-pressure bit body includes a first high-pressure fluid channel and nozzle capable of withstanding fluid pressures greater than 40 kpsi (276 MPa). A bottomhole assembly includes a drill bit with a bit body having fixed cutter and fluid jetting portions. Low and high-pressure channels in the bit body exit in the fixed cutter and fluid jetting portions. The first high-pressure nozzle is coupled to the fluid jetting portion and the high-pressure fluid channel, and a plurality of fixed cutting elements are coupled to the fixed cutter portion. A pressure intensifier is coupled to the drill bit and is configured to increase a pressure of a fluid supplied to the high-pressure fluid channel in the bit body.

A drill bit includes a bit body with high and low fluid pressure bodies. The low-pressure bit body includes a fixed cutting structure, and the high-pressure bit body includes a first high-pressure fluid channel and nozzle capable of withstanding fluid pressures greater than 40 kpsi (276 MPa). A bottomhole assembly includes a drill bit with a bit body having fixed cutter and fluid jetting portions. Low and high-pressure channels in the bit body exit in the fixed cutter and fluid jetting portions. The first high-pressure nozzle is coupled to the fluid jetting portion and the high-pressure fluid channel, and a plurality of fixed cutting elements are coupled to the fixed cutter portion. A pressure intensifier is coupled to the drill bit and is configured to increase a pressure of a fluid supplied to the high-pressure fluid channel in the bit body.

A pulsed power drilling (PPD) component includes a functional gradient of material from a first portion to a second portion of the PPD component. The functional gradient of material provides a greater wear resistance of the first portion relative to the second portion and a greater electrical conductivity or resistivity of the second portion relative to the first portion.

A pulsed power drilling (PPD) component includes a functional gradient of material from a first portion to a second portion of the PPD component. The functional gradient of material provides a greater wear resistance of the first portion relative to the second portion and a greater electrical conductivity or resistivity of the second portion relative to the first portion.

A mining machine applicable to fluidized mining and a mining method therefor are provided herein. A microwave transmitting mechanism, a liquid jet drill rod and a cutter-head are arranged at the head of a first excavation device of the mining machine. The ore body in front is first processed by the microwave transmitting mechanism and the liquid jet drill rod to reduce the strength of the ore body, which facilitates subsequent mining of the ore body, lowers the hardness requirements of the cutter-head, and reduces the wearing of the cutter-head. With this mining machine mining the ore body, the mined ores can be directly converted, under the ground, into resources in the easily transportable form, without transporting the ore to the surface for conversion, which saves the cost of transporting the ore to the surface.

Systems for drilling or tunneling include an assembly for accelerating a projectile into a region of geologic material. An interaction between the projectile and the geologic material extends a borehole and forms debris. The debris may be reduced in size by moving the debris to a crushing device. The reduced-size debris is then moved toward the surface using fluid movement. Water jets or other types of devices may be used to cut or deform a perimeter of a region of geologic material before the projectile is accelerated to control the shape of the borehole and the manner in which debris is broken from the geologic material.

Systems for drilling or tunneling include an assembly for accelerating a projectile into a region of geologic material. An interaction between the projectile and the geologic material extends a borehole and forms debris. The debris may be reduced in size by moving the debris to a crushing device. The reduced-size debris is then moved toward the surface using fluid movement. Water jets or other types of devices may be used to cut or deform a perimeter of a region of geologic material before the projectile is accelerated to control the shape of the borehole and the manner in which debris is broken from the geologic material.