A pressurized fluid flow system for percussive mechanisms comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to the changes in pressure of the pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston. The discharge of fluid from these chambers being conducted through a set of discharge channels and the supply of fluid to the front chamber being conducted through a set of supply channels and a front set of recesses. The supply of fluid to the rear chamber being conducted through a piloted valve.

A pressurized fluid flow system for percussive mechanisms comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to the changes in pressure of the pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston. The discharge of fluid from these chambers being conducted through a set of discharge channels and the supply of fluid to the front chamber being conducted through a set of supply channels and a front set of recesses. The supply of fluid to the rear chamber being conducted through a piloted valve.

The present invention provides a bottom-hole impact-rotation stepping combined unloading rock-breaking efficient drilling system, including a housing, a drive assembly, a universal joint, a transmission shaft, a rotational impact assembly, and a drill bit; the transmission shaft is connected with the housing; the rotational impact assembly includes a rotational transmission assembly for conveying a rotational power to the drill bit and an impact assembly for providing a high frequency axial impact power to the drill bit; when the rotational transmission assembly rotates along with the transmission shaft, the impact assembly applies a high frequency impact force along a drilling axial direction to the rotational transmission assembly; an annular drill bit is disposed at an outer end of a drill bit body of the drill bit; a central drill bit is slidably disposed on an inner ring end surface of the annular drill bit; an inwardly-recessed cylindrical region is formed between a head end of the annular drill bit and a head end of the central drill bit. The present invention further provides a bottom-hole impact-rotation stepping combined unloading rock-breaking efficient drilling method. In the present invention, with entire structural disposal, stepping rock-breaking, bottom hole unloading and impact-rotation drilling can be achieved at the same time, greatly increasing the rock-breaking drilling efficiency.

The present invention provides a bottom-hole impact-rotation stepping combined unloading rock-breaking efficient drilling system, including a housing, a drive assembly, a universal joint, a transmission shaft, a rotational impact assembly, and a drill bit; the transmission shaft is connected with the housing; the rotational impact assembly includes a rotational transmission assembly for conveying a rotational power to the drill bit and an impact assembly for providing a high frequency axial impact power to the drill bit; when the rotational transmission assembly rotates along with the transmission shaft, the impact assembly applies a high frequency impact force along a drilling axial direction to the rotational transmission assembly; an annular drill bit is disposed at an outer end of a drill bit body of the drill bit; a central drill bit is slidably disposed on an inner ring end surface of the annular drill bit; an inwardly-recessed cylindrical region is formed between a head end of the annular drill bit and a head end of the central drill bit. The present invention further provides a bottom-hole impact-rotation stepping combined unloading rock-breaking efficient drilling method. In the present invention, with entire structural disposal, stepping rock-breaking, bottom hole unloading and impact-rotation drilling can be achieved at the same time, greatly increasing the rock-breaking drilling efficiency.

A system for removing debris from a drill hole, the system comprising: a drill system comprising: a drill rod comprising a proximal end, a distal end a first lumen extending between the proximal end and the distal end, and a second lumen extending parallel to the first lumen, the first lumen being fluidically-isolated from the second lumen; a drill bit, the drill bit comprising: a proximal end for mounting to the distal end of the drill rod; a distal end configured to drill into a material so as to form the drill hole; at least one air channel extending between the proximal end of the drill bit and the distal end of the drill bit, the at least one air channel being configured to be fluidically connected to the first lumen of the drill rod when the dual channel drill bit is mounted to the drill rod; at least one vacuum channel extending between the proximal end of the drill bit and the distal end of the drill bit, the at least one vacuum channel being configured to be fluidically connected to the second lumen of the drill rod when the drill bit is mounted to the drill rod; a container fluidically connected to the second lumen of the drill rod; a compressor, the compressor being fluidically connected to the first lumen of the drill rod and fluidically connected to the container; wherein the compressor (i) pumps pressurized air through the first lumen of the drill rod such that the pressurized air passes through the at least one air channel of the drill bit and exits the distal end of the drill bit into the drill hole, and (ii) pumps air out of the container so as to generate a vacuum within the container, which vacuum is fluidically connected to the second lumen of the drill rod and hence to the at least one vacuum channel of the drill bit, such that pressurized air exiting the at least one air channel into the hole and debris in the hole enters the at least one vacuum channel, passes through the second lumen of the drill rod and into the container, such that the debris is collected in the container.

A system for removing debris from a drill hole, the system comprising: a drill system comprising: a drill rod comprising a proximal end, a distal end a first lumen extending between the proximal end and the distal end, and a second lumen extending parallel to the first lumen, the first lumen being fluidically-isolated from the second lumen; a drill bit, the drill bit comprising: a proximal end for mounting to the distal end of the drill rod; a distal end configured to drill into a material so as to form the drill hole; at least one air channel extending between the proximal end of the drill bit and the distal end of the drill bit, the at least one air channel being configured to be fluidically connected to the first lumen of the drill rod when the dual channel drill bit is mounted to the drill rod; at least one vacuum channel extending between the proximal end of the drill bit and the distal end of the drill bit, the at least one vacuum channel being configured to be fluidically connected to the second lumen of the drill rod when the drill bit is mounted to the drill rod; a container fluidically connected to the second lumen of the drill rod; a compressor, the compressor being fluidically connected to the first lumen of the drill rod and fluidically connected to the container; wherein the compressor (i) pumps pressurized air through the first lumen of the drill rod such that the pressurized air passes through the at least one air channel of the drill bit and exits the distal end of the drill bit into the drill hole, and (ii) pumps air out of the container so as to generate a vacuum within the container, which vacuum is fluidically connected to the second lumen of the drill rod and hence to the at least one vacuum channel of the drill bit, such that pressurized air exiting the at least one air channel into the hole and debris in the hole enters the at least one vacuum channel, passes through the second lumen of the drill rod and into the container, such that the debris is collected in the container.

A percussive rock drill bit includes a head having an annular gauge collar and a central island. An annular cutting channel is defined between the collar and the island such that specifically positioned cutting buttons are effective to create an annular ridge in the cut rock face having a reduced rock breaking resistance.

A percussive rock drill bit includes a head having an annular gauge collar and a central island. An annular cutting channel is defined between the collar and the island such that specifically positioned cutting buttons are effective to create an annular ridge in the cut rock face having a reduced rock breaking resistance.

A bottom hole assembly (BHA) and method for drilling a bore with a pneumatic percussion hammer includes an expandable packer surrounding the stem rod connected to the hammer. The packer has an inner surface confronting the outer surface of the stem rod in an axially slideable, sealed relationship. The packer is expanded and fixed in the bore to separate a region of high hydraulic pressure above the packer from a region of lower hydraulic pressure below the packer. The method includes operating the pneumatic hammer and bit, while (i) the stem rod advances with a sliding seal against an inside surface of the expanded packer; (ii) pneumatic pressurization and exhaust for the hammer are guided within the stem rod; and (iii) the exhaust from the hammer is discharged into the lower clearance region surrounding the bit at the bottom of the bore.

A bidirectional cluster hammer reamer (BCHR) for use in a horizontal direction drilling system comprises a plurality of percussive hammers and bits arranged around a central drive rod. The central drive rod is translatable between a forward most position and a rear most position. The central drive rod is translated to the forward most position when the BCHR is being pulled through a previously drilled pilot channel. The central drive rod is translated to the rear most position when a reverse feed force is applied to the BCHR. When in the rear most position, the central drive rod cooperates with an air distribution assembly at the rear of the BCHR to expel a portion of a pressurized fluid to the exterior of the BCHR for clearing accreted debris.