Method, arrangement and machine for full face reaming

A method for powering holes in mountains, the method comprising:

• drilling a front surface in a direction forwards by a rotatable drill head having, on a front side, a plurality of mountain-grinding cutterheads which are located at radially different distances from a centre of the rotatable drill head, the plurality of mountain-grinding cutterheads, independently of each other, being displaceable in the rotatable drill head by being operated by a plurality of hydraulic linear drive arrangements arranged for the plurality of mountain-grinding cutterheads, the plurality of mountain-grinding cutterheads being displaceable from a retracted condition in the rotatable drill head, by the plurality of hydraulic linear drive arrangements, to be conveyable to a mountain-grinding condition projecting from the front side simultaneously with rotation of the rotatable drill head,
• whereby the front surface is drilled in steps in sections along concentric rings of the rotatable drill head which go from an inner smallest circle to an outer largest circle based on successive mountain-grinding cutterheads of the plurality of mountain-grinding cutterheads, with gradually increasing radius from the centre of the rotatable drill head with the rotatable drill head being conveyed in the mountain-grinding condition.