A rotary percussive hydraulic drill including: a body, a shank intended to be coupled to at least one drilling bar equipped with a tool, the shank including a coupling part comprising female coupling splines and male coupling splines which are angularly offset from each other with respect to an extension axis of the shank, a striking piston slidably mounted inside the body along a striking axis and configured to strike the shank, a rotation driving device which is configured to drive the shank in rotation about an axis of rotation substantially coincident with the striking axis, the rotation driving device comprising a coupling member disposed around the shank, the coupling member comprising male coupling splines and female coupling splines which are respectively rotatably coupled with the female and male coupling splines of the shank a front abutment surface which is fixed with respect to the body, the front abutment surfacebeing annular and extending around the shank, the shank being configured to abut against the front abutment surface so as to limit a displacement stroke of the shank forwards, wherein the shank includes an annular bearing flange which is provided on an outer surface of the shank and which includes an annular bearing surfaceconfigured to abut against the front abutment surface, and wherein each of the female and male coupling splines provided on the shank extends from the annular bearing flange and in the direction of the striking piston, each female coupling spline provided on the shank including a bottom surface and a connecting surface which connects the respective bottom surface to the annular bearing flange and which extends forwards away from the extension axis of the shank, the connecting surface of each female coupling spline provided on the shank being at least in part formed by a curved concave surface extending substantially in the extension direction of the respective female coupling spline and having a radius of curvature which is less than the radial height of each of the male coupling splines provided on the shank.

A drilling rig and methods are provided for using multiple types of drilling when installing geothermal systems. The drilling rig can perform sonic drilling such as percussive sonic drilling and a type of non-sonic drilling. Control switching valves are added to the hydraulics of the drilling rig to selectively provide sufficient flow of hydraulic fluid to motors used in the multiple types of drilling, depending on which type of drilling is currently most efficient for the underground formation being drilled. The water pump and hydraulic motor for such have been designed to handle both types of drilling on a small drilling rig frame, thereby allowing for the drilling to occur in space-constrained environments. A method of recycling water used to remove cuttings during drilling to put back downhole is also provided.

A drilling rig and methods are provided for using multiple types of drilling when installing geothermal systems. The drilling rig can perform sonic drilling such as percussive sonic drilling and a type of non-sonic drilling. Control switching valves are added to the hydraulics of the drilling rig to selectively provide sufficient flow of hydraulic fluid to motors used in the multiple types of drilling, depending on which type of drilling is currently most efficient for the underground formation being drilled. The water pump and hydraulic motor for such have been designed to handle both types of drilling on a small drilling rig frame, thereby allowing for the drilling to occur in space-constrained environments. A method of recycling water used to remove cuttings during drilling to put back downhole is also provided.

A reciprocating drive apparatus (10) comprises a housing (12) and a mandrel (14), wherein the mandrel (14) and the housing (12) are configurable to be rotated relative to each other. The apparatus (10) further comprises a reciprocating piston (16) mounted within a piston housing (18) to define a piston chamber (20a), wherein the piston (16) is moveable in reverse first and second axial directions (A,B), and a rotary valve assembly (24) comprising a valve inlet (28) for communicating with a pressure region (P) and a valve exhaust (30) for communicating with an exhaust region (E). The rotary valve assembly (24) is operated by relative rotation between the mandrel (14) and the housing (12) to be cyclically reconfigured between a pressure configuration and an exhaust configuration. When in the pressure configuration the piston chamber (20a) is in pressure communication with the valve inlet (28) and isolated from the valve exhaust (30) to permit the piston to move in the first axial direction (A) in accordance with the piston chamber being pressurised via the valve inlet (28). When in the exhaust configuration the piston chamber (20a) is isolated from the valve inlet (28) and in pressure communication with the valve exhaust (30) to permit the piston chamber to be depressurised and the piston (16) to move in the second axial direction (B). Movement of the piston (16) in at least one of the first and second axial directions (A,B) generates an applied force within the apparatus (10) and/or an applied force output from the apparatus (10).

A reciprocating drive apparatus (10) comprises a housing (12) and a mandrel (14), wherein the mandrel (14) and the housing (12) are configurable to be rotated relative to each other. The apparatus (10) further comprises a reciprocating piston (16) mounted within a piston housing (18) to define a piston chamber (20a), wherein the piston (16) is moveable in reverse first and second axial directions (A,B), and a rotary valve assembly (24) comprising a valve inlet (28) for communicating with a pressure region (P) and a valve exhaust (30) for communicating with an exhaust region (E). The rotary valve assembly (24) is operated by relative rotation between the mandrel (14) and the housing (12) to be cyclically reconfigured between a pressure configuration and an exhaust configuration. When in the pressure configuration the piston chamber (20a) is in pressure communication with the valve inlet (28) and isolated from the valve exhaust (30) to permit the piston to move in the first axial direction (A) in accordance with the piston chamber being pressurised via the valve inlet (28). When in the exhaust configuration the piston chamber (20a) is isolated from the valve inlet (28) and in pressure communication with the valve exhaust (30) to permit the piston chamber to be depressurised and the piston (16) to move in the second axial direction (B). Movement of the piston (16) in at least one of the first and second axial directions (A,B) generates an applied force within the apparatus (10) and/or an applied force output from the apparatus (10).

A hydraulic breaking hammer and method of supporting a percussion piston is provided. The breaking hammer includes a percussion device provided with a reciprocating piston. The piston is supported on a frame at its end portions by a first piston bearing element and a second piston bearing element. The second piston bearing element includes a collar sealing element facing towards a working collar of the piston. The piston bearing elements are easily mountable and dismountable separate components.

A drilling rig and methods are provided for using multiple types of drilling when installing geothermal systems. The drilling rig can perform sonic drilling such as percussive sonic drilling and a type of non-sonic drilling. Control switching valves are added to the hydraulics of the drilling rig to selectively provide sufficient flow of hydraulic fluid to motors used in the multiple types of drilling, depending on which type of drilling is currently most efficient for the underground formation being drilled. The water pump and hydraulic motor for such have been designed to handle both types of drilling on a small drilling rig frame, thereby allowing for the drilling to occur in space-constrained environments. A method of recycling water used to remove cuttings during drilling to put back downhole is also provided.

A down the hole rock drilling machine and a method of drilling rock. The drilling machine includes a reciprocating piston, which has a sleeve-like configuration. Inside a central opening of the piston is arranged one or more fluid passages for conveying pressurized fluid during the work cycle of an impact device of the drill machine.

A down the hole rock drilling machine and a method of drilling rock. The drilling machine includes a reciprocating piston, which has a sleeve-like configuration. Inside a central opening of the piston is arranged one or more fluid passages for conveying pressurized fluid during the work cycle of an impact device of the drill machine.

The present invention relates to a drilling device. The device comprises at least one drill rod, the or each drill rod having a first cylindrical wall defining an elongate chamber for receiving a working fluid to form a fluid column, the length of the fluid column being equal to a total length of the elongate chambers of the or each drill rod. The device also comprises a displacement excitation device arranged at a proximal end of the fluid column and configured to excite the fluid column to cause the working fluid in the fluid column to oscillate, wherein the excitation device is configured to excite the fluid column at an excitation frequency at or within 10% of a natural frequency of the fluid column determined based on the fluid column having a fixed boundary condition at a proximal end thereof. The device further comprises a tool piston moveably mounted at a distal end of the fluid column and a drilling tool connected to the tool piston such that the oscillation of the working fluid in the fluid column imparts an oscillating force to the drilling tool.