Abstract: To modify a given profile of an adit, tunnel, gallery or the like, particularly a circular profile so as to give it the shape of a vault, a sequence of individual recesses are made in the longitudinal direction in the wall of the adit by a boring head advanced in the direction of its axis of rotation and transversely to the longitudinal direction of the adit. The recesses preferably overlap one another. Apparatus for implementing the method comprises a heading device for moving in the direction of the wall of the adit a boring head provided at its front end with tools.

Abstract: A method of and apparatus for sinking essentially vertical bores, in particular large-hole bores, shafts or the like, the bore direction being pre-determined for a bore head or the like, rotatable by means of a set of bore rods, using a device which may be fixed with respect to the borehole wall after a bore section has been bored, wherein the device is released, the bore head is moved in a stationary state into a position suspended on the bore rods and then the direction is determined for the next bore section, the diameter of the bore head for determining the direction of the next bore section being changed from a relatively larger to a relatively smaller size.

Abstract: Producing a vertical or inclined drill hole by full profile drilling taking place upwardly from a starting location and utilizing a rotatable and displaceable drilling tool and a train of drilling rods which lead to the drilling tool, wherein the drilling tool is, together with the train of drilling rods, subjected, in the vicinity of the upper end of the train of drilling rods, to a force applied in the feed direction, at least part of the reaction of this force being transmitted to a counterabutment which can be releasably secured in the drill hole, and the driving torque for the drilling tool being produced at the starting location and mechanically led from there to the drilling tool.

Abstract: A method for drilling boreholes utilizing a plurality of simultaneously operated boring tools. During a drilling operation the loading forces on the tools are measured and constantly compared with a predetermined limiting value representative of a limiting loading value and the variation of a limiting loading value with respect to time. If these limiting values are exceeded at least one working parameter of the tools is adjusted such as feed force, feed speed or track speed of the tools. Apparatus for carrying out the method is also disclosed.