Abstract: Measurement of a track position is carried out in successive measurement sections (15), wherein the relative track position is registered in each case with the aid of a long chord (17), formed by a laser beam (16), which serves as reference line of a measuring system (9). During this; an angle enclosed by the two long chords (17) of two successive measurement sections (15) is measured in order to thereby obtain a spatial curve reproducing the actual position of the track.

Abstract: A welding unit for welding rails of a track includes two unit bodies that can be moved in relation to each other by displacement cylinders along unit guides running parallel to the rails. The displacement cylinders are connected both to pull rods and to a crossbeam. Thus a simple design having high tensile forces is possible.

Abstract: Measurement of a track position is carried out in successive measurement sections (15), wherein the relative track position is registered in each case with the aid of a long chord (17), formed by a laser beam (16), which serves as reference line of a measuring system (9). During this; an angle enclosed by the two long chords (17) of two successive measurement sections (15) is measured in order to thereby obtain a spatial curve reproducing the actual position of the track.

Abstract: For the controlled lowering of a track, a longitudinal inclination of the track is determined at a rear tracing point of a measuring system and stored. For a length reaching back at least 10 meters, a current vertical profile is formed, and a rear compensation straight line is calculated which is superimposed upon the vertical profile and renders a target track position. The rear tracing point is guided by calculation along the rear compensation straight line, so that a compensation value for the position of the measuring chord ensues at a middle tracing point positioned between the rear tracing point and a front tracing point.

Abstract: A machine for welding the rails of a track includes a rail pulling device that grips the rail ends and pulls them together so that they can be welded to one another. Two rail clamps provided for gripping the rails are fastened to the rail pulling device. The rail clamps are each vertically adjustable in their position relative to the rail pulling device by way of a respective adjustment drive in a direction extending perpendicularly to a pulling device plane formed by hydraulic drives of the rail pulling device. With this, the rails can be lifted from ties in a simple manner in order to enable the clamping members of the rail pulling device to grip the rails.

Abstract: A machine for welding rails of a track extending in a longitudinal direction includes a rail pulling device for gripping the rails to be welded to one another. The rail pulling device is connected to a machine frame of the welding machine by way of guides and coupling devices. The rail pulling device is designed for displacement in the longitudinal direction or transversely to the longitudinal direction by means of longitudinal displacement drives and transverse displacement drives, and is also vertically adjustable by means of drives. By means of tilting drives, the rail pulling device can additionally be pivoted about an axis extending in the longitudinal direction.

Abstract: The invention relates to a method for welding two rails (8, 10, 14) of a track using a welding unit (1) of a welding machine (20). According to the method, two rails (8,10,14) each caught by a pair of clamping jaws (6) of the welding unit (1) are moved and welded together while subjecting them to crusher cylinders (3) in the longitudinal direction of the rails. A rail anchor (16) is produced in a so-called terminal-welding step in a working direction (11) upstream of the machine (20) by linking a section of the rail (14) with ties (15) in a non-positive manner. If the actual rail temperature differs from the local neutral temperature, tensions are passed into the rails to be welded together.

Abstract: In a method of tracing a track geometry immediately ahead of a ballast pick-up device of a cleaning machine in a working direction, a first and a second measuring chord are guided on the track by a respective front and rear end point. A versine measured by a first versine sensor of the first measuring chord is stored, in connection with a distance measurement, for registering the rear end point of the first measuring chord as a desired position with respect to a local track point. After the rear end point of the second measuring chord has reached the local track point, the rear end point is displaced until a measurement value corresponding to the stored versine is reached by a second versine sensor, and thus the desired position has been attained.

Abstract: A machine for welding rails of a track extending in a longitudinal direction includes a rail pulling device for gripping the rails to be welded to one another. The rail pulling device is connected to a machine frame of the welding machine by way of guides and coupling devices. The rail pulling device is designed for displacement in the longitudinal direction or transversely to the longitudinal direction by means of longitudinal displacement drives and transverse displacement drives, and is also vertically adjustable by means of drives. By means of tilting drives, the rail pulling device can additionally be pivoted about an axis extending in the longitudinal direction.

Abstract: A machine for welding the rails of a track includes a rail pulling device that grips the rail ends and pulls them together so that they can be welded to one another. Two rail clamps provided for gripping the rails are fastened to the rail pulling device. The rail clamps are each vertically adjustable in their position relative to the rail pulling device by way of a respective adjustment drive in a direction extending perpendicularly to a pulling device plane formed by hydraulic drives of the rail pulling device. With this, the rails can be lifted from ties in a simple manner in order to enable the clamping members of the rail pulling device to grip the rails.

Abstract: In a method of surveying a track (9), a first or mobile measuring vehicle (1) and a second or stationary measuring vehicle (2) are placed at a distance apart from one another on a track section to be measured. A reference line (14) is formed by a laser beam emitted from the stationary measuring vehicle (2). At the start of each measuring cycle, by using a GPS receiver (19), the relative position of the stationary measuring vehicle (2) with reference to a fixedly installed GPS reference station (29) located adjacent to the track section is determined, the said GPS reference station being known within a terrestrial coordinate system. The reference line (14) is aligned with the mobile measuring vehicle (1) on the basis of the determined position data, and the track surveying operation is carried out by advancing the mobile measuring vehicle (1) while changes of the actual track position relative to the reference line (14) are registered.

Abstract: In a method for tamping ballast supporting sequentially arranged ties of a track extending in a longitudinal direction, which comprises a tamping cycle at each one of the ties, the tamping cycle comprises lowering a tamping head carrying tamping tools hydraulicallly reciprocable in the longitudinal direction to immerse the tamping tools in the ballast, reciprocating the tamping tools to tamp the ballast, vibrating the tamping tools in a first tamping cycle phase, discontinuing vibration of the tamping tools in a second tamping cycle phase, raising the tamping head to lift the tamping tools out of the ballast, and moving the tamping head from tie to tie.

Abstract: In a method of tracing a track geometry immediately ahead of a ballast pick-up device of a cleaning machine in a working direction, a first and a second measuring chord are guided on the track by a respective front and rear end point. A versine measured by a first versine sensor of the first measuring chord is stored, in connection with a distance measurement, for registering the rear end point of the first measuring chord as a desired position with respect to a local track point. After the rear end point of the second measuring chord has reached the local track point, the rear end point is displaced until a measurement value corresponding to the stored versine is reached by a second versine sensor, and thus the desired position has been attained.

Abstract: A method for the contactless scanning of a track bed profile extending perpendicularly to a longitudinal extension of the track, comprises the steps of simultaneously effectuating the scanning and a measurement of any deviation from a desired track level at a location of the scanning, recording the scanned track bed profile, and calculating an amount of ballast required for raising the track to the desired track level and for uniformly distributing the ballast in the track bed in dependence on the measured track level deviation and the recorded scanned track bed profile.

Abstract: A control system for monitoring a work train for performing track maintenance operations has a computer connected to receive information from a multitude of work vehicles constituting the work train. A respective vehicle identifying device is associated with each work vehicle, the vehicle identifying device being connected communicate with the computer (e.g., via a control line) and configured for storing vehicle characteristics defining the respective work vehicle. The computer connected to the control line includes a display for visually indicating, in the case of a malfunction report concerning a particular work vehicle, the respective vehicle characteristics in connection with the position of the respective vehicle within the work train.

Abstract: A control system for monitoring a work train for performing track maintenance operations has a computer connected to receive information from a multitude of work vehicles constituting the work train. A respective vehicle identifying device is associated with each work vehicle, the vehicle identifying device being connected communicate with the computer (e.g., via a control line) and configured for storing vehicle characteristics defining the respective work vehicle. The computer connected to the control line includes a display for visually indicating, in the case of a malfunction report concerning a particular work vehicle, the respective vehicle characteristics in connection with the position of the respective vehicle within the work train.

Abstract: A method for the contactless scanning of a track bed profile extending perpendicularly to a longitudinal extension of the track, comprises the steps of simultaneously effectuating the scanning and a measurement of any deviation from a desired track level at a location of the scanning, recording the scanned track bed profile, and calculating an amount of ballast required for raising the track to the desired track level and for uniformly distributing the ballast in the track bed in dependence on the measured track level deviation and the recorded scanned track bed profile.

Abstract: For detecting a tie position in a track, a non-contact scanning device on a track-bound machine is associated with an odometer for recording a distance travelled by the machine. The scanning device is configured as distance measuring device for registering vertical distance measurement values between the machine and track, and is operatively connected to a control unit. The control unit is designed for continually and sequentially subdividing a measuring span, correlated to the distance travelled, into a succession of tie detection sections and adjacent ballast detection sections, which are associated with a ballast region situated between the ties. The tie detection section includes distance measurement values differing only slightly from one another, while the ballast detection section contains a sequence of abruptly fluctuating distance measurement values. As a result of detecting the tie position, a working unit, such as a tamping unit, can be centered over the tie automatically.

Abstract: A track work machine for mobility on a track extending in a longitudinal direction and supported on ballast, includes a machine frame extending in the longitudinal direction and having a front end and a rear end. An excavating device is mounted on the machine frame at the rear end and has a leading ballast pick-up unit arranged underneath the track and a trailing discharging end. A conveyor belt is associated with the discharging end and provided for receiving and transporting excavated ballast. A front undercarriage and a rear undercarriage are provided for supporting the machine frame on the track, the rear undercarriage being mounted on the machine frame for displacement in the longitudinal direction from a transit travel position, in which the rear undercarriage is situated between the discharging end and the ballast pick-up unit of the excavating device, in the direction towards the front undercarriage.

Abstract: In a method of surveying a track (9), a first or mobile measuring vehicle (1) and a second or stationary measuring vehicle (2) are placed at a distance apart from one another on a track section to be measured. A reference line (14) is formed by a laser beam emitted from the stationary measuring vehicle (2). At the start of each measuring cycle, by using a GPS receiver (19), the relative position of the stationary measuring vehicle (2) with reference to a fixedly installed GPS reference station (29) located adjacent to the track section is determined, the said GPS reference station being known within a terrestrial coordinate system. The reference line (14) is aligned with the mobile measuring vehicle (1) on the basis of the determined position data, and the track surveying operation is carried out by advancing the mobile measuring vehicle (1) while changes of the actual track position relative to the reference line (14) are registered.