Abstract: A connection rod (1) for rock drilling includes a first rod part (2) whidh has an external thread (4) provided at one end thereof, wherein the end of the rod opposite to the one end includes an end portion (6) which carries an internal thread (5), wherein the end portion (6) is joind to the first rod part (2) by friction welding and wherein the end portion (6) has been heat treated prior to being joined to the first rod part (2). The invention also relates to a method of producing such a connection rod.

Abstract: An arrangement for replenishing lubricating grease in drill cutters (3) that include a conical outer barrel (7) which is rotatable about a shaft (5) disposed centrally in the cutter, wherein there is provided in the cutter shaft (5) a passageway (16) that extends along the shaft from the cutter end of largest diameter and that connects with a transverse passageway (18) which opens into a bearing-accommodating space (13) in the cutter for delivering lubricating grease to the space (13), and wherein a lubricating nipple (19) is provided on the cutter end wall of largest diameter and functions to allow lubricating grease to be released from the bearing-accommodating space (13).

Abstract: A drilling machine including a frame, a tower, a rotary head, and a rod handling device. The frame is supported for movement over the ground and the tower is mounted on the frame. The rotary head is movable along the tower and is engageable with the drill string for rotating the drill string. The rod handling device is movable along the tower and operable to selectively support the drill string. The rod handling device is biased to a first position along the tower.

Abstract: The present invention relates to a connection rod (1) for rock drilling comprising a first rod part (2) which has an external thread (4) provided at one end thereof, wherein the end of the rod opposite to said one end includes an end portion (6) which carries an internal thread (5), wherein the end portion (6) is joined to the first rod part (2) by friction welding and wherein the end portion (6) has been heat treated prior to being joined to said first rod part (2).

Abstract: A joint device in extension drill equipment for percussive drilling is so constructed that, besides transmitting compressive pulses in the drill string in the direction towards the drill bit, it also by reflection transforms tensile pulses in the drill string into compressive pulses. Preferably, the joint device includes members that are axially movable relative to each other and provided with interacting surfaces, and an element connecting the members. Compressive pulses cause these surfaces to abut each other under pressure, while tensile pulses cause the surfaces to become separated. Also preferably, the joint device includes a structure for absorbing kinetic energy generated in the device by torsion pulses in the drill string.

Abstract: A device for reducing friction between surface planes sliding against each other in axial thrust bearings between the shaft end and roller in rotary roller bits and rollers for rock and earth boring, especially at full size tunnel driving. A friction reducing groove is arranged eccentrically in relation to the axes of the shaft end and the roller in at least one of the surface planes sliding against each other. Said groove is filled with material having a friction reducing and/or lubricating effect.