Abstract: A machine for profiling and distributing ballast of a track, having a frame supported on on-track undercarriages and lateral ballast pick-up devices which are adjustably fastened to the frame, wherein each ballast pick-up device is actuated by a conveyor drive. In this, the machine is designed in such a way that, in an inoperative position, the upper contours of the machine are arranged below a delimiting plane which slopes downward in the working direction and extends through a field of vision of a driver's cabin of a rail vehicle to be coupled to the machine at the rear end thereof. Thus, the machine can be employed as a leading wagon of the rail vehicle, wherein sufficient visibility from the driver's cabin to the track is ensured.

Abstract: A machine for repairing a ballast bed has an undercutter that defines a direction of movement of the repairing machine, and a distributor for dividing a flow of ballast entering from the undercutter into a rear flow of exiting ballast and a separate front flow of exiting ballast. At least one rear screening machine is positioned behind the undercutter in the direction of movement and is fed by the rear flow of exiting ballast. At least one front screening machine is positioned in front of the undercutter and fed by the front flow of exiting ballast, and the distributor has a variator for varying the ratio between the separate first and the second flows of exiting ballast.

Abstract: In the course of rehabilitation of a ballast bed of a track, while creating a track construction site (10), old bulk material (6) to be removed is stored on a plurality of storage wagons (2) connected to form a loading train (7). Parallel thereto, new bulk material (9) pre-deposited on a plurality of storage wagons (2) connected to form a loading train (8) is introduced into the track construction site (10). The introduction of the new bulk material (9) into the track construction site (10) is controlled automatically in dependence on a volume of the old bulk material (6) removed from the track construction site (10).

Abstract: A machine group for cleaning ballast of a track includes a first machine, having an endless clearing chain for ballast cleaning, and a second machine preceding the former with regard to a working direction and having a pick-up device for picking up cleaned ballast pre-deposited on the track. A third machine is arranged to precede the second machine. The third machine has two shoulder excavating devices for picking up the ballast located in a shoulder region of a ballast bed, and a second screening plant for cleaning the picked-up ballast.

Abstract: In a first method step for cleaning a ballast bed (8) of a track (9), the ballast (6) picked up from a bedding section (7) adjoining sleepers ends (30), after having been cleaned, is introduced underneath the track (9) immediately after the removal—carried out in a second method step—of the ballast (6) located underneath the sleepers.

Abstract: A machine group for cleaning ballast of a track includes a first machine, having an endless clearing chain for ballast cleaning, and a second machine preceding the former with regard to a working direction and having a pick-up device for picking up cleaned ballast pre-deposited on the track. A third machine is arranged to precede the second machine. The third machine has two shoulder excavating devices for picking up the ballast located in a shoulder region of a ballast bed, and a second screening plant for cleaning the picked-up ballast.

Abstract: A machine for renovating a track includes the following: a transverse chain segment of an excavating chain is designed shorter than a crosstie length of new crossties. A ballast plow is disposed relative to a longitudinal machine axis between the transverse chain segment of the excavating chain and the device for placing the new crossties. A width—extending normal to the longitudinal machine axis—of the ballast plow is designed greater than the crosstie length of the new crossties.

Abstract: An installation for cleaning a ballast bed contains a first machine frame and a second machine frame coupled to the former, each being equipped with two vertically adjustable crawler tracks and two on-track undercarriages. A receiving unit of a clearing chain for picking up ballast is disposed between the crawler tracks of the first machine frame. A ballast discharge device is arranged between the two crawler tracks of the second machine frame, the latter having a screening installation.

Abstract: A machine for collecting tie plates strewn along a rail bed includes a frame adapted for travel along a railroad in a forward direction. A pickup drum having magnetic properties is rotatably supported by the frame and extends over a bed portion of the railroad. A top drum is mounted at a location that is higher and forward of the pickup drum and rotates parallel to the pickup drum. An endless conveyor circulates around the pickup and top drums, and a separation drum is disposed between the pickup drum and the top drum along an ascending portion of the endless conveyor. The separation drum includes a magnetized rim that can lift ferrous objects but not tie plates from the endless conveyor.

Abstract: For the purpose of rehabilitation, a ballast bed of a track is taken up in the form of an upper bed layer by a first clearing device and cleaned. The bulk material accruing in the process is discharged in front of the first clearing device—with regard to the working direction—laterally upon the ballast bed in a bed region. The latter can only be covered by the second clearing device which is configured to be of greater width—with regard to a transverse direction of the track—than the first clearing device. Thus, it is possible to intermediately store bulk material, accruing in a front end region of a machine, on the ballast bed for later use.

Abstract: In a method for the continuous renewal of a ballast bed (41) of a track from which the rails and sleepers have been removed, by carrying away old ballast (42) and depositing cleaned ballast or new ballast (44) on the underlying surface (46) from which the old ballast (42) has been removed, a removal device (22) which can travel in the working direction (x) continuously picks up the old ballast (42) of the ballast bed (41). The excavated material is conveyed away from the excavation area and possibly passed on for ballast cleaning At the same time, cleaned ballast or new ballast (44) is continuously deposited in the working direction (x) on the underlying surface (46) from which the old ballast (42) has been removed, to form a new ballast bed (43). The removal device (22), as part of an excavating machine (10) traveling in the working direction (x) on the old ballast bed (41), is arranged downstream of the running gear (14, 16) of the excavating machine (10).

Abstract: For the purpose of rehabilitation, a ballast bed of a track is taken up in the form of an upper bed layer by a first clearing device and cleaned. The bulk material accruing in the process is discharged in front of the first clearing device—with regard to the working direction—laterally upon the ballast bed in a bed region. The latter can only be covered by the second clearing device which is configured to be of greater width—with regard to a transverse direction of the track—than the first clearing device. Thus, it is possible to intermediately store bulk material, accruing in a front end region of a machine, on the ballast bed for later use.

Abstract: In a method of rehabilitating a ballast bed of a track by excavating contaminated ballast and conveying the excavated contaminated ballast by a first conveyor band unit to a screening unit for cleaning the excavated contaminated ballast, the ballast bed is rehabilitated selectively, in dependence on the degree of contamination of the ballast, in a first or second operating stage. The first operating stage comprises the steps of excavating an upper layer of the ballast by a first excavating device which precedes a second excavating device, in an operating direction, and conducting the excavated upper ballast layer to the first conveyor band unit while, at the same time, the remainder of the ballast is excavated by the second excavating device and is conducted to a second conveyor band unit for disposal.

Abstract: The invention relates to the replacement of old ties of a railway track by new ties. This aim can be achieved by spreading the two rails apart from each other. The reception of ballast gravel for producing a recess of ballast is carried out in a region below of the sleeper head of a ballast bed, which is located adjacent to the region of the old sleepers along their longitudinal axis. The received ballast gravel is temporarily stored and, once the new sleepers have been deposited, thrown off for the purpose of ballasting. In parallel and prior to the deposit of new sleepers, excess ballast gravel is ploughed in the recess of ballast so as to produce a leveled surface of ballast.

Abstract: In a method for the continuous renewal of a ballast bed (41) of a track from which the rails and sleepers have been removed, by carrying away old ballast (42) and depositing cleaned ballast or new ballast (44) on the underlying surface (46) from which the old ballast (42) has been removed, a removal device (22) which can travel in the working direction (x) continuously picks up the old ballast (42) of the ballast bed (41). The excavated material is conveyed away from the excavation area and possibly passed on for ballast cleaning. At the same time, cleaned ballast or new ballast (44) is continuously deposited in the working direction (x) on the underlying surface (46) from which the old ballast (42) has been removed, to form a new ballast bed (43). The removal device (22), as part of an excavating machine (10) travelling in the working direction (x) on the old ballast bed (41), is arranged downstream of the running gear (14, 16) of the excavating machine (10).

Abstract: A truck (1) for a railroad rehabilitation machine comprises a railway truck (3) and a tank (2) resting on the railway truck (3) in a removable manner. The tank (2) comprises a holding structure (5) extending along a predetermined direction (X), at least one first conveyor (8) mounted within the holding structure (5) to transport incoherent material along the predetermined direction (X) internally of the holding structure (5), and an element (22) for laying the holding structure (5) on the truck (3) for railway transport. A process for making a truck for a railway rehabilitation machine comprises the steps of arranging a railway truck (3) having a support platform (4), arranging a tank (2) for trucks of railroad rehabilitation machines in accordance with the invention and laying the tank (2) on the platform (4) of the railway truck (3) in a removable manner.

Abstract: The invention relates to a method for introducing a flowable and foamable reaction mixture from the top into a ballast body having sleepers embedded therein, in which method said mixture is introduced into the ballast body laterally of the sleepers, notably preferably depending on the height of the ballast body at the point of application, and in a quantity that is all the larger the more upwards in the ballast body the application point is situated, wherein the mixture is adjusted in such a way that the foam formation process will begin only when the front of the mixture flowing downwards inside the ballast body has reached the bottom side or the region in the vicinity thereof of the ballast body so that the foam formation is carried out within the ballast body from the bottom towards the top.

Abstract: A truck (1) for a railroad rehabilitation machine comprises a railway truck (3) and a tank (2) resting on the railway truck (3) in a removable manner. The tank (2) comprises a holding structure (5) extending along a predetermined direction (X), at least one first conveyor (8) mounted within the holding structure (5) to transport incoherent material along the predetermined direction (X) internally of the holding structure (5), and means (22) for laying the holding structure (5) on the truck (3) for railway transport. A process for making a truck for a railway rehabilitation machine comprises the steps of arranging a railway truck (3) having a support platform (4), arranging a tank (2) for trucks of railroad rehabilitation machines in accordance with the invention and laying the tank (2) on the platform (4) of the railway truck (3) in a removable manner.

Abstract: In a method of rehabilitating a ballast bed of a track by excavating contaminated ballast and conveying the excavated contaminated ballast by a first conveyor band unit to a screening unit for cleaning the excavated contaminated ballast, the ballast bed is rehabilitated selectively, in dependence on the degree of contamination of the ballast, in a first or second operating stage. The first operating stage comprises the steps of excavating an upper layer of the ballast by a first excavating device which precedes a second excavating device, in an operating direction, and conducting the excavated upper ballast layer to the first conveyor band unit while, at the same time, the remainder of the ballast is excavated by the second excavating device and is conducted to a second conveyor band unit for disposal.

Abstract: An arrangement of an excavating chain for conveying ballast of a track bed comprises a guide comprising a transverse guide section articulately connected to longitudinal guide sections defining a guide channel having an end glide track along which the excavating chain is guided. The end glide track of the transverse guide section is curved around the joints connecting the ends of the transverse guide section to the adjoining longitudinal guide sections, the end glide track enclosing an acute dihedral angle ? with an imaginary plane of elongation of the end glide track of a respective one of the longitudinal guide sections whereby the excavating chain is deflected from the transverse to the longitudinal guide sections solely by contact with the end glide track.

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: An arrangement of an excavating chain for conveying ballast of a track bed comprises a guide comprising a transverse guide section articulately connected to longitudinal guide sections defining a guide channel having an end glide track along which the excavating chain is guided. The longitudinal guide sections are connected to the ends of the transverse guide section joints arranged below the second plane extending centrally through the end glide track and the excavating chain is deflected solely from the transverse to the longitudinal guide sections by frictional contact with the end glide track adjacent the joints.

Abstract: A track rehabilitation machine comprises an elongated machine frame supported on the track by undercarriages for movement in an operating direction, the machine frame having two ends.

Abstract: A method of cleaning encrusted ballast comprises the steps of screening the encrusted ballast to separate detritus from the ballast, washing the screened ballast with water while removing the separated detritus on a conveyor belt unit, clarifying the washing water to produce a clarified water portion and washing water sludge, and disposing of the washing water sludge by moving it to the detritus on the conveyor belt unit for common removal with the detritus.

Abstract: A ballast cleaning machine comprises a machine frame supported on the track by undercarriages for movement in an operating direction. Two vertically and laterally adjustable endless ballast excavating chains are sequentially arranged in a longitudinal direction for excavating ballast from the ballast bed, and a track lifting device mounted on the machine frame. A first conveyor arrangement conveys the ballast excavated by the first endless ballast excavating chain to a first screening installation, a second conveyor arrangement conveys the ballast excavated by the second endless ballast excavating chain to a second screening installation, and a third conveyor arrangement distributes the cleaned ballast to the ballast bed.

Abstract: A ballast cleaning machine comprises a first machine frame and a second, trailing machine frame linked thereto. Ends of the machine frames are supported on the track by undercarriages for movement of the machine in an operating direction. A vertically and laterally adjustable endless excavating chain as well as a track lifting device is mounted on each machine frame. An upper layer of the ballast bed is excavated by the first excavating chain, the track is lowered to the remaining ballast bed layer, and the remaining ballast bed layer is immediately thereafter excavated by the second excavating chain. The excavated ballast is cleaned in a common screening installation, and the cleaned ballast is distributed at a trailing end of the second machine frame to the ballast bed.

Abstract: A track rehabilitation machine comprises an elongated machine frame supported on the track by undercarriages for movement in an operating direction, the machine frame having two ends.

Abstract: A ballast cleaning machine comprises a machine frame supported on the track by undercarriages for movement in an operating direction. Two vertically and laterally adjustable endless ballast excavating chains are sequentially arranged in a longitudinal direction for excavating ballast from the ballast bed, and a track lifting device mounted on the machine frame.

Abstract: A ballast cleaning machine comprises a machine frame supported on the track by undercarriages, one of the undercarriages at an end of the machine frame being displaceable in the longitudinal direction. Two vertically and laterally adjustable endless ballast excavating chains are sequentially arranged in the longitudinal direction for excavating ballast from a ballast bed and mounted on the machine frame between the undercarriages, and drives vertically and laterally adjust, and revolve, each endless ballast excavating chain. A respective operator's cab is mounted on the machine frame in view of each endless ballast excavating chain, a control for the drives being arranged in each operator's cab. At least two track lifting devices are mounted on the machine frame, and a screening installation for cleaning ballast is mounted on a car linked to the machine frame.

Abstract: A clearing chain is mounted on a mobile track maintenance machine for excavating ballast material from a track bed. The chain is composed of shovel-type clearing members for gathering the ballast and intermediate chain elements positioned between the adjacent clearing members and connected thereto by means of chain joints, thus forming an endless chain. Each intermediate chain element comprises two chain joints spaced from one another in the longitudinal direction of the clearing chain. The chain joints are designed for receiving a hinge pin articulatedly mounted in the joint and releasably fastened to the clearing member.

Abstract: A machine for distributing ballast in a track bed comprises a machine frame supported on the track by undercarriages for mobility in an operating direction, a ballast plow adjustably mounted on the machine frame for distributing the ballast in the track bed, drives for adjusting the ballast plow relative to the machine frame, a contactless sensor arranged ahead of the ballast plow in the operating direction for detecting an existing track bed profile extending perpendicularly to the longitudinal direction, a position indicator for indicating a change in the position of the ballast plow relative to the machine frame, and a control for the drives comprising a memory storing a desired track bed profile.

Abstract: A machine for withdrawing bulk material from a track, in particular ballast aterial, includes a bulk material clearing device vertically adjustably secured to a machine frame and including a rotatable, endless scraper chain positioned between the rails of the track immediately above the track. A first conveyor extends in longitudinal direction of the machine frame and has a receiving end which receives bulk material from the clearing device. Immediately trailing the clearing device in the operating direction is a vertically adjustable sweeping device which includes a sweeping broom rotatable about a pivot axis extending horizontal and perpendicular to the longitudinal direction of the machine frame. A second conveyor immediately trails the sweeping device in the longitudinal direction of the machine frame and includes a receiving end for receiving bulk material from the sweeping broom.

Abstract: A track work machine for excavating material from a bed supporting a track comprises a machine frame, undercarriages supporting the machine frame on the track for movement in an operating direction, a vertically adjustable endless excavating chain operable to be trained, and revolve, around the rails in a plane inclined relative to the longitudinal direction, and a ballast clearing device mounted on the machine frame between the undercarriages, the ballast clearing device comprising a carrier frame affixed to the machine frame, a vertically and transversely adjustable plate-shaped clearing tool, and drives for vertically adjusting the clearing tool over a distance of at least 65 cm between a raised rest position and an operating position wherein the clearing tool is immersed in a respective one of the cribs, and for adjusting the clearing tool transversely to the longitudinal direction.

Abstract: A track maintenance machine for excavating material from a track bed comprises a machine frame comprising an upwardly recessed machine frame section, undercarriages supporting the machine frame on the track for movement in an operating direction, and sequentially arranged on the machine frame in the operating direction, a ballast receptacle comprising chutes for discharging the ballast from the receptacle, an inclined, vertically adjustable and revolvable endless excavating chain comprising a drive at an upper end for revolving the chain, the excavating chain being mounted underneath the upwardly recessed machine frame section for excavating the material from the bed, a track lifting device, a conveying arrangement arranged to remove the received excavated material and having an inlet end arranged below the upper excavating chain end to receive the excavated material therefrom, the ballast discharging chutes being arranged immediately behind the conveying arrangement inlet end in the operating direction, and

Abstract: An apparatus for reconstructing railway track systems while simultaneously clearing away the bed of the old track system. A sliding seal driver is used to secure the trench formed by the removal of the old track foundation as the old track is cleared away. A new trench is cut as the apparatus proceeds on the same path as the old track. The seal driver includes lateral shields securing the trench walls as well as ground shields resting on the bottom of the trench. The lateral shields are of such lengths to secure the trench walls over the entire work area.

Abstract: A machine for aspirating ballast from a bed supporting a track comprises a machine frame and undercarriages supporting the machine frame on the track for mobility therealong. A vacuum generator and a ballast storage receptacle are mounted on the machine frame. A suction tube is connected to the vacuum generator, the suction tube terminating in a tubular end section having a longitudinal axis and defining a suction opening at one end thereof for aspirating the ballast, the tubular end section being rotatable about the longitudinal axis. A displacement mechanism attaches the suction tube to the machine frame for vertically and transversely displacing the tubular suction tube end section, the displacement mechanism comprising drives for vertically and transversely displacing the tubular suction tube end section, and a drive is provided for rotating the tubular suction tube end section in a direction of rotation.

Abstract: An excavating and conveying chain assembly for transporting ballast of a track includes a plurality of chain links hingedly connected to each other for traveling along a transport path. Connected to each chain link is a scraper blade which has a link-distal end formed with a plurality of projecting scraper fingers. Each scraper finger is of two-part configuration, with a first part being formed by an engagement member secured to the scraper blade and jutting out therefrom in a finger-like manner, and with a second part being formed by a protective cap that is pushed onto the engagement member and detachably secured thereto by a fastener.

Abstract: A machine for treating a ballast bed underneath a track comprises a machine frame extending in a longitudinal direction and supported on the track by undercarriages for movement in an operating direction, a suction unit mounted on the machine frame, the suction unit comprising a vertically and laterally adjustable suction pipe having a suction opening for aspirating ballast from the ballast bed, a conveyor band arranged on the machine frame to convey the aspirated ballast away from the suction unit, and a ballast discharge device mounted on the machine frame rearwardly of the suction pipe in the operating direction, the ballast discharge device comprising a hopper. A conveyor arrangement extends in the longitudinal direction on the machine frame and has an input end arranged to receive the aspirated ballast from the conveyor band and an output end arranged to discharge the aspirated ballast into the hopper.

Abstract: A suction unit (76) provided with a suction pipe (80) having a suction opening (81) for sucking off crushed rock and being vertically and laterally adjustable is allocated to a machine (57) for treating the ballast bed of a track (60) with a machine frame (58) supported on rail travelling undercarriges (59). In addition, there is provided a clearing apparatus (62) disposed at a distance from the suction opening (81) in the longitudinal direction of the machine and provided with an endless clearing chain (64) rotatable by a drive (63) for removing the crushed rock disposed below the track (60). Like the suction pipe (80), it is provided with separate drives (82, 99) for vertical and lateral adjustment independently from one another.

Abstract: The subgrade supporting a ballast bed for a track is rehabilitated by (a) lifting the track off the ballast bed, removing an upper,portion of the ballast from the ballast bed, comminuting the removed ballast to obtain gravel, storing the gravel, and laying the track on a remaining portion of the ballast bed, in a first stage, (b) lifting the track off the remaining ballast bed portion, removing the ballast of the remaining ballast bed portion until the subgrade is exposed, and laying the track on the exposed subgrade, in a second stage, and (c) lifting the track off the subgrade, discharging the stored gravel on the subgrade, planing and compacting the gravel on the subgrade until a protective layer for the subgrade is obtained, and laying the track on the protective subgrade layer, in a third stage.

Abstract: A machine for working on a ballast bed supporting a track comprises a machine frame, undercarriages supporting the machine frame on the track, and a ballast storage receptacle and a suction arrangement on the machine frame. The suction arrangement comprises a suction unit and a suction conduit connected to the suction unit, the suction conduit terminating in a vertically and transversely adjustable suction snout defining a suction opening for aspirating ballast into the ballast storage receptacle. A compressed air conduit connects a compressed air generating unit on the machine frame to the ballast storage receptacle for supplying compressed air thereto, and a blow conduit is connected to the ballast storage receptacle for blowing stored ballast out of the receptacle.

Abstract: A ballast cleaning machine comprises a machine frame supported on undercarriages running on the track and carrying a ballast screening arrangement, a ballast excavating device including a revolvable excavating chain arranged to deliver excavated ballast to the screening arrangement for cleaning the excavated ballast, a conveyor arrangement disposed to receive the cleaned ballast from the screening arrangement and to discharge the cleaned ballast for support of the track, a laterally and vertically adjustable suction pipe having a suction opening at one end for receiving ballast, and a vacuum device connected to an opposite end of the suction pipe for applying sub-atmospheric pressure to the suction opening and thereby to suck up ballast through the suction pipe.

Abstract: The installation for the rehabilitation of a ballast bed supporting a track including two rails comprises a first machine, and a second machine, the machines being supported on the track by undercarriages for movement in an operating direction, and the second machine preceding the first machine in the operating direction.

Abstract: An arrangement for installing a protective layer between a subgrade and a layer of ballast of a track bed includes an excavating unit to remove ballast from underneath the track and a subgrade stabilizing unit by which additives are disposed directly over the exposed subgrade and blended underneath the track with the subgrade for formation of a protective layer following a leveling and compacting process. Removed and cleaned ballast is then laid by a conveyor over the new protective layer.

Abstract: A mobile machine for withdrawing ballast from a ballast bed includes two receptacles, each of which including a separate intake port and discharge outlet, with a suction tube being selectively connectable to the intake ports of the receptacles. In order to selectively seal the intake ports in an air-tight manner, each intake port accommodates a closing element so as to allow an alternate emptying and filling of the receptacles without interruption of the withdrawal of ballast.

Abstract: A mobile arrangement for rehabilitating a ballast bed by installing a protective layer between a subgrade and layer of ballast at a construction site of the track includes an excavation unit for continuously removing old ballast from the ballast bed to expose the subgrade and a rock crusher unit which receives at least a portion of withdrawn old ballast for comminution thereof. Comminuted old ballast is then laid over the exposed subgrade for forming at least part of the protective layer.

Abstract: A ballast machine for plowing ballast from the outer ends of rail supporting cross ties of a railroad bed. A ballast tie plow assembly is mounted to the frame of the ballast machine for vertical movement thereon. The tie plow assembly includes ballast engaging blades which are disposed for biased, pivotal movement responsive to engagement of the blades with an obstruction on the railroad bed or cross ties. Means are provided for vertical positioning of the tie plow assembly.

Abstract: A mobile machine for aspirating ballast from a ballast bed comprises a machine frame extending in a longitudinal direction and supported by undercarriages running on a track. Mounted on the machine frame are a ballast aspirating device comprising a short suction inlet pipe defining a suction inlet port, and a ballast excavating device vertically adjustable by drive means linking the ballast excavating device to the machine frame. The ballast excavating device comprises a substantially horizontally extending beam having opposite ends, a guide roller mounted on each beam end and an endless ballast excavating chain trained over the guide rollers, the beam being pivotal about a vertical axis at one of the beam ends and arranged in an operating position laterally adjacent one of the tie ends at one of the ballast bed shoulders and the suction inlet port being vertically adjustable in said operating position.

Abstract: A ballast planing machine includes a machine frame supported by undercarriages for movement in an operating direction along a track and comprised of a leading carrier frame which supports a vertically adjustable ballast plow arrangement and a further carrier frame which is linked to the leading carrier frame and supports an operator's cabin and a vertically adjustable, rotary sweeping broom. Mounted to the further carrier frame is also a negative pressure generator of a suction unit for removing excess ballast during movement of the machine frame in operating direction. The suction unit includes a suction tube which communicates with the negative pressure generator and extends in longitudinal direction beyond the machine frame to terminate in a suction nozzle which projects beyond the rearward end of the machine frame.

Abstract: A mobile arrangement for rehabilitating a ballast bed by installing a protective layer between a subgrade and layer of ballast at a construction site of the track includes an excavation unit for continuously removing old ballast from the ballast bed to expose the subgrade and a rock crusher unit which receives at least a portion of withdrawn old ballast for comminution thereof. Comminuted old ballast is then laid over the exposed subgrade for forming at least part of the protective layer.