Abstract: A drill head of a ground drilling device includes a drill bit and an attachment which can be fastened to the drill bit, wherein at least one dowel pin is provided for holding the attachment on the drill bit, and the drill bit has one or more receptacles for a dowel pin, wherein the receptacle is enlarged with respect to the radius of the dowel pin.

Abstract: A drilling head for a percussive displacement ground drilling device with a first drilling head section and a second drilling head section, the first drilling head section having discharge ducts, and the second drilling head section having a cross section that increases in the longitudinal direction, wherein the second drilling head section includes a plurality of step-shaped areas.

Abstract: The invention relates to a drill head of a ground drilling device having a drill bit and an attachment which can be fastened to the drill bit, wherein at least one dowel pin is provided for holding the attachment on the drill bit, and the drill bit has one or more receptacles for a dowel pin, wherein the receptacle is enlarged with respect to the radius of the dowel pin.

Abstract: A drilling head for a percussive displacement ground drilling device with a first drilling head section and a second drilling head section, the first drilling head section having discharge ducts, and the second drilling head section having a cross section that increases in the longitudinal direction, wherein the second drilling head section includes a plurality of step-shaped areas.

Abstract: A percussion drilling device for drilling in earth includes at least one housing section for a main piston, and a ring insert arranged in the housing section in front of the main piston so that the ring insert transmits at least part of the energy of the main piston onto the housing. The ring insert is attached to the housing by a shrink-fit connection.

Abstract: A percussion boring device with an impact piston is mounted within a housing and driven in a cyclic back and forth movement. In a first switch position, the impact piston strikes a front impact surface, in order to drive the percussion boring device in a first movement direction, and, in a second switch position, the impact piston strikes a rear impact surface, in order to drive the percussion boring device in a second movement direction. For the reversal of the movement directions, a guide tube fixed to the housing, and a control sleeve which can be axially shifted on the guide tube, are provided, and the impact piston can be axially shifted on the control sleeve. The control sleeve includes two sections which are connected to one another by a movable connection.

Abstract: A percussion boring device with an impact piston is mounted within a housing and driven in a cyclic back and forth movement. In a first switch position, the impact piston strikes a front impact surface, in order to drive the percussion boring device in a first movement direction, and, in a second switch position, the impact piston strikes a rear impact surface, in order to drive the percussion boring device in a second movement direction. For the reversal of the movement directions, a guide tube fixed to the housing, and a control sleeve which can be axially shifted on the guide tube, are provided, and the impact piston can be axially shifted on the control sleeve. The control sleeve includes two sections which are connected to one another by a movable connection.

Abstract: A ram boring device has a pressurized-fluid driven striking piston in a device housing and a rotating reversing device configured to urge the striking piston from a forward operation to a reverse operation, in order to create oblique or horizontal bores in the ground. A piston chamber of a rotary piston drive is connected to a control fluid line.

Abstract: A percussion drilling device for drilling in earth includes at least one housing section for a main piston, and a ring insert arranged in the housing section in front of the main piston so that the ring insert transmits at least part of the energy of the main piston onto the housing. The ring insert is attached to the housing by a shrink-fit connection.

Abstract: A ground-drilling device includes a basic body and a drill head movably mounted in relation thereto in the longitudinally axial direction, wherein a free space, which is variable in its size owing to the movable mounting, is formed between the drill head and the basic body, and a sealing element for sealing the free space with respect to the environment, wherein the sealing element is designed as a valve element which opens when an overpressure is present inside the clearance, in order to produce a pressure compensation, and which is closed when a negative pressure is present inside the clearance, in order to prevent a pressure compensation.

Abstract: A ram boring device has a pressurized-fluid driven striking piston in a device housing and a rotating reversing device configured to urge the striking piston from a forward operation to a reverse operation in order to create oblique or horizontal bores in the ground, in which the piston chamber of a rotary piston drive is connected to a control fluid line.

Abstract: The invention relates to an earth drilling device (1) for boring a borehole into the soil and/or for drawing a line (9) into an underground passage, comprising at least one system line (4, 6) extending from the earth drilling device to a start region, wherein the system line is designed in an electrically insulating manner.

Abstract: A boring element of a ground boring device includes a housing having a receptacle, a transmitter arranged in the receptacle of the housing and supported in the receptacle for movement in a longitudinal-axial direction of the boring element, and a front buffer connecting the transmitter with the housing. The transmitter moves towards a rear in the receptacle as a result of a deformation of the front buffer, when a rear percussive impulse is applied to the boring element, without the transmitter coming directly into contact with another part of the boring element.

Abstract: The invention relates to a method for inserting a pipe (4) via a pit (1) into an underground borehole, wherein the pipe is flattened before entering the pit, and wherein the pipe is redirected within the pit in the direction of the axis of the borehole, so as to re-deform the pipe before entering the borehole.

Abstract: The invention relates to a ram boring device for creating horizontal boreholes, having an impact piston which moves in an oscillatory manner within a casing of the ram boring device and of which the impact frequency or impact intensity can be varied by displacing the center position of the impact piston inside the casing.

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 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 pipe guide adapter for drawing pipes into a channel with the aid of a traction means is provided with ribs which are arranged conically on a base pipe. The ribs ensure guidance of the pipe and, at the same time, a simple construction of the adapter. In addition, the pipe guide adapter can be provided with rollers, which are arranged in the free spaces between the ribs and facilitate the guide function of the pipe guide adapter.

Abstract: An insertion coupling for a boring rod assembly with at least two coupling elements is disclosed. The coupling elements include at least one corresponding tapered coupling face pair constructed to produce play-free clamping when pressing forces are applied to the insertion coupling.

Abstract: A ground-drilling device includes a basic body and a drill head movably mounted in relation thereto in the longitudinally axial direction, wherein a free space, which is variable in its size owing to the movable mounting, is formed between the drill head and the basic body, and a sealing element for sealing the free space with respect to the environment, wherein the sealing element is designed as a valve element which opens when an overpressure is present inside the clearance, in order to produce a pressure compensation, and which is closed when a negative pressure is present inside the clearance, in order to prevent a pressure compensation.