Abstract: The invention relates to a boring head for a ground-boring device displacing earth with a percussive action, comprising at least three boring head sections, of which the first section has a form optimized for the loosening and for guiding the device, the second section is optimized with regard to the radial displacement of the earth with low resistance to motion, and the third section has a fixed connection to the housing of the ground-boring device. Improved transmission of the advancing forces to the earth and consequently an improved advance of the ground-boring device can be achieved by at least two of the boring head sections being designed so as to be axially movable relative to one another in the longitudinal direction.

Abstract: An apparatus for mixing a powdery medium with a fluid includes a mixing vessel which can be filled with the fluid and which has a feed for the fluid, an inlet for the powdery medium and an outlet for the fluid mixed with the powdery medium, and at least one mixing screw arranged inside the mixing vessel and driven by a rotary drive.

Abstract: In a method for multistage manufacture of a borehole between two earth shafts, a drilling device drills in a first direction a pilot bore between a starting shaft and an end shaft and lines the pilot bore with pipes. Subsequently, the pilot bore is expanded in a second direction opposite to the first direction to form an expansion bore which is simultaneously lined with pipes, while accumulating soil is transported into the end shaft in opposition to the second direction with the aid of a screw conveyor.

Abstract: A pneumatically reversible ram boring device includes a percussion piston (8) that is situated in a casing (1) and is movable back and forth by operation air supplied via an operational-air supply via an operational-air line (5), a control pipe (4, 36, 54) having at least one control opening (13), an outer pipe (15, 65), and a control sleeve (10, 60) that can be displaced by compressed air from a control chamber (16, 66). An essentially torsion-resistant operational-air line (5) can be rotatably connected to a rotary valve (4, 40, 70) that supplies the control chamber with operational air or vents air from the chamber.

Abstract: The invention relates to a system for the overground operation of underground sewer tools, especially of expander and pulling heads comprising a rod assembly that is rigid when pushed and a supporting device absorbing shear or tractive forces.

Abstract: The invention relates to an apparatus and a method for joining a pipe conduit to a drilling device, expanding device or pull-in device, in which a pulling-force generator arranged in the drilling device, expanding device or pull-in device exerts a compressive force on a pipe conduit, to be pulled in, via a pulling means and an adapter and thereby holds the individual short pipes of the pipe conduit together and reduces the mechanical stress to which the short pipes are subjected.

Abstract: The invention relates to a geothermal system for exchanging heat with the water of a public supply line, wherein the heat exchanger is arranged within the supply line and is used in modular form as a pipe section.

Abstract: The invention relates to a rod coupling for rod segments for use in horizontal earth boring, wherein the ends of the rod segments can be interconnected and are fixed by means of a cross pin.

Abstract: The invention relates to a coupling system for rod segments for use in horizontal earth boring, wherein the ends of the rod segments are interlinked via a separate sacrificial element which can be used as a predetermined breaking point or which allows the rod segments to be pivoted relative each other.

Abstract: A cutting device for cutting or bursting a pipeline includes a basic body having at least one cutting or perforating element, wherein the cutting or perforating element discontinuously cuts the pipeline in the longitudinal direction or at least discontinuously weakens the pipe material.

Abstract: In an angle drilling device for introducing or expanding wellbores that are inclined in relation to the horizontal, an angle-adjustable bore rig for a movable feed drive is arranged on a base frame that is movable for example. The bore rig is pivotally connected with the base frame while a connection, for example a link bar, extends between the feed drive and the base frame and has a constant length to effect during travel of the feed drive a change in incline of the bore rig as a consequence of the distance between both pivot points for the bore rig and the point of articulation of the connection.

Abstract: In a method and an apparatus for replacing old underground conduits (4), the old conduit (4) is first laid bare with the aid of a ground drilling device (8) with an overdrilling head and then, in turn, a new conduit (5) is drawn in with the aid of the drill rods (7) and at the same time—in a uniform operating step—the old conduit is pulled out of the ground.

Abstract: A rod assembly driver which is alternately acting in two opposing directions includes two opposing grip jaws for a rod assembly, which grip jaws are hingedly connected to one another in the form of a parallelogram by pairs of plates.

Abstract: The invention relates to a boring head for a ground-boring device displacing earth with a percussive action, comprising at least three boring head sections, of which the first section has a form optimized for the loosening and for guiding the device, the second section is optimized with regard to the radial displacement of the earth with low resistance to motion, and the third section has a fixed connection to the housing of the ground-boring device. Improved transmission of the advancing forces to the earth and consequently an improved advance of the ground-boring device can be achieved by at least two of the boring head sections being designed so as to be axially movable relative to one another in the longitudinal direction.

Abstract: The invention relates to a tensioning device in particular for tensioning pipe sections upon an abutment, including a traction element, an adapter, and a tensioning device for applying the tension force, and a sliding brake.

Abstract: In a method for introducing a geothermal probe into the earth, a geothermal probe is introduced in a radiating manner with the drill head into the earth. After the drilling operation, the drill head remains in the earth.

Abstract: A pneumatically reversible ram boring device includes a percussion piston (8) that is situated in a casing (1) and is movable back and forth by operation air supplied via an operational-air supply via an operational-air line (5), a control pipe (4, 36, 54) having at least one control opening (13), an outer pipe (15, 65), and a control sleeve (10, 60) that can be displaced by compressed air from a control chamber (16, 66). An essentially torsion-resistant operational-air line (5) can be rotatably connected to a rotary valve (4, 40, 70) that supplies the control chamber with operational air or vents air from the chamber.

Abstract: In a method for multistage manufacture of a borehole between two earth shafts, a drilling device drills in a first direction a pilot bore between a starting shaft and an end shaft and lines the pilot bore with pipes. Subsequently, the pilot bore is expanded in a second direction opposite to the first direction to form an expansion bore which is simultaneously lined with pipes, while accumulating soil is transported into the end shaft in opposition to the second direction with the aid of a screw conveyor.

Abstract: In an angle drilling device for introducing or expanding wellbores that are inclined in relation to the horizontal, an angle-adjustable bore rig for a movable feed drive is arranged on a base frame that is movable for example. The bore rig is pivotally connected with the base frame while a connection, for example a link bar, extends between the feed drive and the base frame and has a constant length to effect during travel of the feed drive a change in incline of the bore rig as a consequence of the distance between both pivot points for the bore rig and the point of articulation of the connection.

Abstract: In a method of installing a borehole heat exchanger in the earth, a channel is formed in the earth by means of a pushing device, thereby causing a compression of the earth as a result of earth being displaced, and inserting a borehole heat exchanger in the channel, causing an elastic component of the earth to move toward the heat exchanger as the earth relaxes in order to provide an intimate contact between the earth and the heat exchanger. Installation of the borehole heat exchanger in elastically displaced earth ensures not only a stable and lasting securement of the heat exchanger in the earth but also the intimate contact between earth and heat exchanger wall so important for heat exchanger.