Lkab Wassara Ab

Magnus Hörman

Peter Johansson

Magnus Fridsell

Fredrik Egerström

Martin Öhnström

Peter F Johansson

The invention relates to a rotary device () for a down-the-hole hammer (), which rotary device is accommodated in a rotation motor housing () and mounted behind a drill housing () for transferring a torque to a drill bit () and a pressurized drive fluid () to a striking mechanism () for the drill bit. The rotary device includes a cam curve with a plurality of drive lobes (-) and working chambers () along a circumference in the rotation motor housing (), a rotor disc () carrying a plurality of radially movable vanes (-), which are accommodated in piston tracks (-) in the rotor disc. Characteristics of the rotary device are that it includes; an odd integer of a number of drive lobes (-), which is equal to or higher than three; an odd integer of a number of working chambers (), which is equal to or higher than three; an odd integer of a number of vanes (-), which is equal to or higher than three, and wherein said number of vanes are simultaneously pressurized in each working chamber ().

Drive device for rotatable operation of a drill bit of a down-the-hole hammer

The invention concerns a method to establish communication between the inner cavity of a drill string and the surrounding material down in a drill hole () during the use of a down-the-hole drill unit with a drill string (), a down-the-hole hammer drill (), and a source of pressurized medium () that delivers a medium under pressure to the down-the-hole hammer drill. Communication is established through: (a) that a tube section () of the drill string () is assigned openings (), (b) that a piston () with an axial channel () is arranged, (c) that the piston () is inserted into the cavity of the tube section () in a manner that allows sliding, (d) that the piston () allows driving fluid to be led through a channel () from the source of pressure () to the down-the-hole hammer drill (), (e) that the piston () is assigned a first part () of a recovery means (), which part can be united with a second part (), (f) that a lifting arrangement () is arranged at the surface level, (g) that the second connector () of the recovery means () is lowered into the drill hole (), the piston () is fished up out of the drill hole and the compartment in the cavity of the tube section () that is formed is used as a measurement compartment.

Method and arrangement to establish during down-the-hole drilling communication between the cavity of the drill string and the surrounding material

The invention concerns a drill bit, intended to be used with a down-the-hole drill and comprising a drill head () with a front surface provided with drill pins () and a shaft (), whereby the shaft is narrower than the drill head and intended to be inserted in a manner that allows axial sliding into the end of a drill chuck that is a component of a down-the-hole drill and which shaft has a rear end part () that is somewhat thickened with a plane striking surface () against which a hammer piston () that is a component of the down-the-hole hammer drill is arranged to impact, that the drill head when viewed along its axial direction has a cylinder-shaped forward part () provided with cuttings channels (), a rear cylinder-shaped part () that is located for the reception of drill cuttings at the same level or somewhat below the bottom () of the cuttings channels, whereby the diameter (D) of the forward part is greater than the diameter (D) of the rear part. In a drill bit that has high performance and a long useful life, and that is furthermore well-suited to be used for directed drilling, the cylinder-shaped forward part () of the drill head () has an axial length (L) from the main plane of the front surface to a shoulder plane () located between the drill head () and the shaft () that is greater than the axial length (L) of the cylinder-shaped rear part () of the drill head.

Drill bit for a down-the-hole drill

An arrangement for a down-the-hole hammer drill, for use in soil consolidation by jet grouting, and comprising a cylindrical machine housing, an impact mechanism driven by pressurised fluid that impacts onto a drill bit mounted in a chuck in the machine housing that allows reciprocating motion, whereby the machine housing has a central supply line for the driving fluid to the impact mechanism in which channels in the drill bit constitute outlets for used driving fluid. The machine housing is provided with a grouting nozzle for jet grouting, that the grouting nozzle is directed in a sideways direction and arranged at the periphery of the wall of the machine housing, that a rinsing channel for conducting a grouting mixture through the machine housing to the said grouting nozzle is arranged whereby the rinsing channel for the grouting mixture is separate from the supply line for the driving fluid of the impact mechanism.

Growing community of inventors

Älta, Sweden

Magnus Hörman