Abstract: A drilling assembly for percussive drilling includes at least two of a drill bit, a drill rod and a guide adapter. A peripheral surface of the shoulder on the drill rod is at least partially encased in both radial and axial directions inside the mounting sleeve of the drill bit or the mounting sleeve of the guide adapter, and/or the peripheral surface of the shoulder on the guide adapter is at least partially encased in both radial and axial directions inside the mounting sleeve of the drill bit.

Abstract: A rock drill insert made of cemented carbide includes hard constituents of tungsten carbide (WC) in a binder phase of Ni—Cr, or Ni—Co—Cr, and a balance of WC and unavoidable impurities. The cemented carbide has a 3.5-18 wt % binder phase. The binder phase has >0 wt % Ni. The mass ratio Cr/(Ni+Co) is 0.02-0.19. A difference between the hardness at 0.3 mm depth at some point of the surface of the rock drill insert and the minimum hardness of the bulk of the rock drill insert is at least 30 HV3.

Abstract: A pressure accumulator, rock breaking machine and method of storing pressure energy. The accumulator includes a casing and an elastic membrane arranged inside the casing. The membrane divides an inner space of the casing into two separate pressure spaces. A gas space is prefilled with pressurized gas. On the opposite side of the membrane is a hydraulic space for receiving hydraulic fluid. The membrane is a hat-like element having side walls, a mounting flange at its open end and a closed top end. The mounting flange of the membrane is mounted between the casing and a flange element. The accumulator is without a screen. The flange element is provided with a sealing for sealing a piston.

Abstract: An apparatus, rock drilling rig, method and computer program for executing navigation for a rock drilling rig in a mine tunnel. The rock drilling rig is positioned at faces of rounds and is navigated before initiating drilling. The navigation is executed without a predetermined tunnel line. The realized tunnel line is formed by combining navigation data on several rounds. Length and direction of the round to be drilled next may be adjusted according to need.

Abstract: A method is provide, which includes the steps of receiving a three-dimensional tunnel model of an underground tunnel system of a worksite, receiving two-dimensional position data having sets of x coordinate values and y coordinate values of a mobile device in the underground tunnel system, performing a vertical plane ray cast operation in the tunnel model at a mobile device position defined by an x coordinate value and an y coordinate value in the received position data, and determining a z coordinate value for the mobile device position on the basis of the ray cast operation and at least one earlier resolved z coordinate value for a preceding mobile device position.

Abstract: The present disclosure relates to a system and a method of controlling the movement of a tracked mobile mining machine having one or more articulated vehicle units. The control system works by taking input from manual or automated input means, the input serving as a set operating value for at least one driving parameter. The controller generates control signals, which are sent to regulating means that actuate the motor of the mobile mining machine. Using sensors on the machine, actual values of the driving parameter are measured in real-time and fed to the controller for comparison with the original set values. Any difference in the values is compensated for when the controller sends control signals to the regulating means causing readjustment of the driving parameter of the mining machine. The control system is applicable to crawler-driven powered vehicle units to ensure synchronous crawler movement for both linear and non-linear paths.

Abstract: The present disclosure relates to a rock drill bit for a percussive drilling hammer positioned at the cutting end of a hammer. The drill bit includes a head, an elongated shank connected to the head at a front end of the bit, a head-shank transition area where the head connects to the shank, an anvil at the rear end of the shank for receiving the impact of the piston, a plurality of buttons provided at the front face of the head configured to engage the material to be crushed in the intended direction of drilling, and a plurality of flushing passages extending through the head and having at least one opening at the front face of the head. An angle formed between the head and the shank at the head-shank transition area is greater than 100 degrees.

Abstract: A drill string including an elongate hollow main length section and a male spigot portion provided at the second end and having an externally threaded section and a non-threaded shank positioned axially intermediate the main length section and the threaded section. The shank includes a transition section positioned adjacent the main length section or a radially projecting shoulder at the second end. The transition section has an outside diameter that increases in a direction from the male spigot portion to the main length section or the shoulder. The cross-sectional shape profile of the outer surface of the transition section in the plane of the longitudinal axis has a segment of an ellipse having semi-major axis (a) and a semi-minor axis (b), wherein the ratio of the semi-major to semi-minor axes (a:b) is within the range 2b<a<8b.

Abstract: A roller cutter for a drill head for raise boring. The roller cutter having a shaft with a longitudinal center line, a hub rotatably mounted on the shaft, and a seal retainer located between the axial ends of the hub and the shaft at least arranged at one end of the roller cutter. The seal retainer supports a primary cutter seal providing sealing between the shaft and the hub in both axial and radial directions. A secondary cutter seal is located between the seal retainer and the hub, such that the secondary cutter seal provides sealing in the axial direction.

Abstract: A drilling rig includes a carrier, a ground support attached to the carrier for supporting the carrier on the ground, a drilling boom attached at a first end to the carrier, a feed beam attached to a second end of the drilling boom, a drilling unit attached movably along the feed beam, a ground pin attached to the feed beam for supporting the feed beam onto the ground, and control means configured for performing the steps of at least: receiving ground support force information indicative of force applied by the ground support to the ground, and detecting ground contact state of the ground pin on the basis of the received ground support force information.

Abstract: A sensor assembly for a rock bolt, wherein the rock bolt includes a central rod, a split tube and a wedge anchor assembly fitted around the central rod, a rock plate, and a nut for attachment to an outer end of the central rod. The sensor assembly includes a distance sensor, a bracket for attaching the distance sensor to an outer portion of the split tube, an elongate spacing member configured to be fitted around the split tube between the nut and the rock plate to keep the nut and the rock plate spaced apart. The spacing member has an opening extending along at least a portion of the length thereof, the opening being sized large enough to allow movement of the bracket along a portion of the length of the spacing member with the distance sensor attached to the outer portion of the split tube by the bracket.

Abstract: A down-the-hole drilling assembly activated by fluid under pressure includes a casing having an axially rearward and forward end, a piston arranged movably inside the casing, a plurality of fluid passages for feeding and discharging pressurized fluid into and out of a working chamber for generating reciprocating movement of the piston, a drill bit at the forward end and provided with an anvil facing towards the piston for receiving impacts therefrom and an annular drive sub surrounding at least a portion of a shank and cooperating with the bit to form fluid passages extending length-wise along the shank. The drive sub has a concave arcuate groove extending circumferentially to form a chamber for collecting fluid from the hammer exhaust and redistributing a volume of the collected fluid from channels formed between complimentary splines of the drive sub and splines of the bit to flushing holes arranged in the bit.

Abstract: A rock drilling arrangement includes an impact device having a frame, pressure chambers in the frame, and a piston arranged in the impact device. The arrangement further includes a rear mounting arrangement for attaching the impact device to a carriage, a front mounting arrangement for attaching the impact device to a machine component, at least one fore pressure accumulator arranged on a front side of the rear mounting arrangement in an axial direction of the piston, and at least one rear pressure accumulator arranged on a back side of the rear mounting arrangement. The fore pressure accumulator and the rear pressure accumulator are connected to one of the pressure chambers and arranged to absorb pressure fluctuations in the pressure chambers.

Abstract: A drill bit for percussion drilling includes a drill bit body including a front surface. The front surface includes a first circular area arranged transverse and coaxially to the axis of the drill body, a second area surface surrounding the first area surface, and a third area surface surrounding the second area surface. A number of buttons are arranged in the second and third area surfaces. The button body of each button has a forward end surface. The buttons are arranged in circular recesses extending substantially transverse from the second surface and third area surface into the drill bit body. The recesses have a radius corresponding to the button body radius and a depth corresponding to the length of the button body, such that the button bodies are fitted within the drill bit body with the forward end surface exposed in the second and third area surfaces.

Abstract: A drill string for rotary drilling of underground mining machines includes a first elongate drill string member and a second elongate drill string member. The first member has a main section and a male end, and the second member has a main section and a female end. The male and female ends each have respective threads to provide a thread coupling between the male and female ends, the thread coupling enabling the male end to be secured inside the female end such that the male and female ends overlap axially. A thread lead of the respective threads of the male and the female ends are greater than a diameter of the male end and the female end.

Abstract: A rock drilling unit and method for charging drilled holes. The rock drilling unit includes a feed system for feeding initiators and rock breaking material into the drilled holes. The rock drilling unit is also provided with one or more communicating devices for communicating with the wireless initiators.

Abstract: A down the hole drilling assembly having a drill tube adapter, an elongate casing, a fluid powered piston, a top working chamber, a bottom working chamber, a top sub and an exhaust system, wherein the exhaust system is moveable with respect to the drill string. The top sub includes an exhaust valve arranged for opening and closing the connection between the at least one exhaust passage and the at least one exhaust port.

Abstract: A method for a zone passage control system for an underground worksite having a plurality of operation zones for autonomously operating mobile vehicle operations includes the steps of associating a first passage control unit with a first zone and a second zone, detecting state parameter information of the first zone and the second zone, merging the first zone and the second zone into a fusion zone on the basis of the state parameter information of the first zone and the second zone, and adapting the zone passage control system to allow a first autonomously operating mobile vehicle to pass the first passage control unit in the fusion zone without interrupting operation of a second autonomously operating mobile vehicle in the first zone and/or the second zone.

Abstract: A disc cutter for a cutting unit used in an undercutting operation and a method of producing the same. The disc cutter including an annular disc body made of a metal alloy or metal matrix composite having a first side, a second side arranged substantially opposite to the first side and a radially peripheral part. At least one metal alloy, metal matrix composite or cemented carbide cutting part is mounted in and substantially encircling the radially peripheral part of the disc body which protrudes outwardly therefrom to engage with the rock during the mining operation. The at least one cutting part is made from a material having a higher wear resistance than the material used for the disc body, wherein the disc body and the cutting part are joined by diffusion bonds.

Abstract: A rock bolt for installation within a bore formed in rock strata having an elongate shaft with the leading end for installation into the bore and a trailing end projecting from an open end of the bore. A locking nut is threadably attached to the trailing end and is arranged to display product information and the like at a display face. The display face is recessed axially into the nut to provide protection against damage to the display face that may otherwise render the information unreadable.