A method employing an apparatus in conjunction with a hammer-drill to penetrate composite metal and non-metal structure or structures including, for example, thick metal or rebar encountered during concrete, rock or masonry boring operations without requiring a change in drill equipment.

A drilling tool, in particular a rock drilling tool, for a portable machine tool, includes an axis of rotation, at least one spiral path, and at least one wear surface transition. The at least one spiral path is coiled about the axis of rotation along the axis of rotation and includes at least one wear surface having at least one bandwidth. There is a change in the at least one bandwidth of the at least one wear surface at a position of the at least one wear surface transition.

To provide a method for forming an anchor hole and a diameter expansion device by which a centrifugal force can be appropriately adjusted when a cutting-blade portion is moved in a radial direction by the centrifugal force to grind a diameter expansion portion. In a method for forming an anchor hole for a post-installed anchor in which a diameter expansion drill bit is inserted and rotated in a prepared-hole portion bored in a concrete fixing body and a cutting-blade portion of the diameter expansion drill bit is moved in a radial direction by a centrifugal force to grind a part of the prepared-hole portion to form a diameter expansion portion, the minimum value of the centrifugal force applied to grind the diameter expansion portion is 0.75 N and preferably 1.1 N.

A drill bit for chiseling stone includes an impact face at an insertion end of the drill bit, a hollow shank, where a delivery passage is defined within the hollow shank, and a drill head, where the drill head has, at a front end of the drill head, a cutting edge, an intake opening, and an intake passage. The intake passage connects the intake opening to the delivery passage. A cross section of the intake passage increases from the intake opening to the delivery passage.

A method employing an apparatus in conjunction with a hammer-drill to penetrate composite metal and non-metal structure or structures including, for example, thick metal or rebar encountered during concrete, rock or masonry boring operations without requiring a change in drill equipment.

A drill bit that serves to remove mineral materials and that consecutively has on a longitudinal axis (6) a drill head (2), a helix (3), an insertion end (4) and an impact surface (7) on the end face of the insertion end (4) that faces away from the drill head (2) and that serves to absorb impact along a direction of impact (8), is provided. The drill head (2) has at least two cutting edges (13) and at least two blades (20). The cutting edges (13) each have a cutting face (16) and a free face (17).The blades (20) run parallel to the longitudinal axis (6) and adjoin the cutting edges (13). The blades (20) each have a radially projecting tooth (24) that adjoins the cutting face (16), whereas it adjoins the free face (17) either only partially or not at all. The axial dimension (29) of the tooth (24) is smaller than the axial dimension (25) of the blade (20).

A drill bit for chiselling rock includes an impact face at an insertion end of the drill bit, a hollow shank, where a delivery passage is defined within the hollow shank, and a drill head, where the drill head has, at a front end of the drill head, a plurality of cutting faces, an intake opening, and an intake passage. The intake passage connects the intake opening to the delivery passage. The intake opening has a noncircular cross section.

A control method for the use of a core drilling system including a core drill and a feed device for driving the core drill along a machine holding device. The method includes the steps of determining the end of a core drilling operation on the basis of reaching a predetermined threshold value for at least one corresponding predefined drilling parameter; and of selecting a reversing mode for retracting a drilling tool out of a borehole at a reversing rotational speed which corresponds to a multiple of a predetermined tapping rotational speed of the drilling tool at the beginning of the core drilling operation.

A control method for a core drill and a feed device for driving the core drill along a machine holding device, including the method steps: moving the core drill in a first direction; detecting the surface position of a material based on reaching a threshold value for at least one feed device parameter as a first reference value; moving the core drill in a second direction; operating the core drill in a tapping mode; moving the core drill in the first direction; detecting the surface position of a material based on reaching a threshold value for at least one corresponding drilling parameter as a second reference value; activating a water supply; and activating a regulating and control unit for adapting at least one drilling parameter as a function of at least one parameter of the feed device. A feed device for driving a core drill along a machine holding device for the use of the method, a core drill for the use of the method, as well as a core drilling system including a core drill and a feed device for driving the core drill along a machine holding device for the use of the method.

A tool for machining materials has a main part and one or more blades. The main part is made of a low-alloy steel. The socket is welded to the main part, and the blade edges are made of a hard metal. The hard metal contains at least 82 vol. % of tungsten carbide and a metallic binder made of a cobalt-nickel-based alloy. The hardness of the hard metal is greater than 1350 HV10. The socket has a sintered composite, and 40 vol. % to 60 vol. % of the composite is composed of a metal carbide and a metallic binder. At least 95 vol. % of the metallic binder is made of nickel, and the hardness of the composite is less than 800 HV10.