Abstract: The train comprises transport vehicles (16) for the new (T1) and old (T2) ties, followed by a storage vehicle (12) for the ties, a railroad car (1) as a dismantling car, articulated to the storage vehicle (12), and a laying unit (17) constructed in a manner such as to be mobile between a working state and a state of rest when running light. When working, this mobile unit (17) bears at one end on the car (1), for example via a wheel gear (22), and at the other end on a running support (24) which moves on the new track (R2). In the state of rest, the mobile unit (17) is moved and loaded onto the car (1), the running support (24) being retracted. The running support can also be formed by a railroad vehicle (26) or by a bissel truck (28), coupled to the car when running light.

Abstract: The carriage comprises a frame (10) with two end axles (10A, 10B), between which is located a bissel truck (10C, 16), the chassis (16) of which is articulated on one of these end axles (10A), and a guide bar (18) articulated between the axle (10C) of the bissel truck and the other end axle (10B). At least one wheel (C) of the bissel truck functions as a rail tracer. Grinding heads (T1, T2; T5, T6) are articulated on this chassis (16) and on this guide bar (18) by means of connecting rods (S1, S2; S5, S6) and are thus guided independently of the positions of the end axles, in such a way that the contact point of each grinding wheel (M1, M2; M5, M6) follows the rails independently of curves, thus compensating the cambers at these points. The carriage can have several successive bissel trucks articulated on one another, each guiding grinding heads, or a system of levers for the indirect guidance of the grinding heads, this system being controlled by a bissel measuring truck.

Abstract: The machine which comprises serveral grinding heads per stretch of rail and which may be moved with respect to height by means of lifting devices is equipped with an installation for automatically lifting grinding wheels (M1to M8) in the critical zones of switches, namely frog and blade zones.

Abstract: By means of several measuring sensors (C1 to C6), the distance (h1 to h6) from several generatrices (s1) to s6) of the rail-head profile to a reference base are measured and are compared as actual values with predetermined desired distance values. The grinding heads, which are set to a specific generatrix and which grind a facet at an angle of inclination corresponding to the position of each generatrix, are always lifted off automatically when this facet reaches the position corresponding to the desired distance value in relation to the reference base. Because the distance to a particular generatrix, on which is located the vertex line of two adjacent facets of a pair of facets, is measured as an actual value, any two adjacent facets can be checked simultaneously by means of one and the same measuring sensor (C1 to C6).

Abstract: A levelling and shifting machine and a transmitter system (1) are used, the latter being installed on a carriage parked on the track and transmitting a spreading beam in the horizontal plane for levelling and a spreading beam in the vertical plane (Fr) for shifting, these beams defining an absolute measuring base. The receivers for levelling and shifting, which are installed on a measuring carriage of the machine, are designed for self-centering relative to the line of incidence of one of the said beams or the other during each measurement. In a curve of the track (3), the vertical beam (Fr) defines a cord of this curve, and the set position of the receiver defines the current value of the pitch of the curve (fm.sub.0, fm.sub.1 etc). A computer calculates the desired value of the pitch (f.sub.0, f.sub.1 etc.) and the variation (y.sub.0, Y.sub.1 etc.) between the two values, the latter variation determining the shifting correction.

Abstract: A train for carrying out the renewal of a railroad switch or crossing in a track comprises two chassis with a girder between them supported by two cranes on the respective chassis. Cross beams on the girder have hooks for gripping the switch or crossing. The girder is suspended from the cranes by rotary joints and an auxiliary winch has a cable connected to the switch or crossing off-center to provide for tilting the switch or crossing. At least one of the chassis is provided at its four corners with articulated arms and extensible columns provided with bogies for running on side rails. The arms can be swung in so that the bogies can run on standard gauge track.

Abstract: This device for controlling a railroad track making or repairing machine comprises on the one hand a single laser emitter mounted on a skip standing on the track or the lay-out ahead of the machine, notably a tamping, levelling and lining machine, emits a first fan-shaped or sweeping beam in a horizontal plane and a second fan-shaped or sweeping beam in a vertical plane, and on the other hand two laser receivers mounted on the machine and adapted to adjust themselves automatically as a function of the impact line of one or the other of said laser beams at positions corresponding to the desired positions of the working members of the machine, the laser emitter being mounted on a support permitting its rotation about its track-parallel axis between two end positions spaced 90 degrees apart, these angular positions corresponding the one to the beam in the horizontal plane for levelling operations and the other to the beam in the vertical plane for shifting operations.

Abstract: A railroad track relaying train has, in addition to the cars for transporting the ballast screening machines and a car equipped with power-wrenches for fixing the tie-screws, a sequence of working cars including a tie-and rail-removing car, a ballast clearing car, and a tie and rail laying car. These cars have bogie trucks at both ends and are interconnected by means of coupling frames adapted to bear the adjacent ends of the working cars in the trackless working area and supported by caterpillar trucks adapted to keep the working cars on the selected path, when moving on the ballast cleared track bed. Each caterpillar truck is provided with hydraulic cylinders for raising and lowering the coupling frame relative to the respective truck and with mechanisms for driving and steering the truck.

Abstract: A method for the improvement and drainage of a railway track employs a train comprising a working frame-car to carry out the method whereby it is made possible to dismantle and reassemble the track together with its infrastructure. The old track spans are removed, ballast and earth are excavated from the track and replaced by a layer of sand and by new ballast which are distributed, levelled and compacted mechanically. All these operations are taking place in succession through and within the empty frame of said frame-car as the latter is stationary bridging the working site. Two travelling gantries are provided on the train and equipped both with a lifting device for a track span and a lifting and tipping device for buckets. The working car is also equipped with means for excavating, digging, levelling and compacting.

Abstract: A rail road rail grinding truck adapted to grind the top surface of the rail comprises at least one grinding unit of which the position is adjustable by means of a cylinder and also of rail-engaging bearing shoes following the undulations of the rail surface. Each unit comprises an adjustable stop member responsive to a servo-action regulation device as a function of the grinding wheel wear and also of the rail undulations, so that the point of contact between the wheel and the rail cannot fall below the grinding base determined by the bearing shoes.

Abstract: A method for the improvement and drainage of a length of railway track employs a train to carry out the method whereby it is made possible to dismantle and reassemble the length of track together with its infrastructure. Ballast and earth are excavated from the track and replaced by a layer of sand which is distributed and compacted mechanically through an empty frame of a working truck of the train. Two travelling gantries are provided on the train and equipped both with a lifting device for a length of track and a lifting and tipping device for buckets. The working truck is also equipped with a strip for levelling a platform and a tamper. These two members are mounted on a common chassis supported by travelling on the two side parts of the empty frame of the working truck within the travelling supports for the gantries so that the levelling-tamping chassis may move freely by passing below the gantries.

Abstract: A railroad track relaying train comprises, in addition to the cars for transporting the ballast screening machines and a car equipped with power-wrenches for fixing the tie-screws, a sequence of working cars including a tie- and rail-removing car, a ballast clearing car, and a tie and rail laying car, these cars being interconnected by means of coupling frames supported by caterpillar trucks adapted to keep the working cars on the selected path. The tie and rail removing car comprises an elevator capable of lifting and rotating at least one tie or a track span around ballast conveyors, in order to deposit at least one tie or track span upon a transport element. The train is capable of performing all of the operations necessary for removing the old track, excavating and screening the old ballast, and laying the new track on the screened ballast, without stopping its forward motion when removing the old track.

Abstract: To measure undulatory wear of the rails, a carriage moving along a railroad track has three measuring bases formed by girders each supported on two rollers and each having a rail sensor providing a measurement of deformation of the rail intermediate the support rollers defining the respective measuring base. The measuring bases have different lengths to provide measurements of the amplitude of undulations of given wavelength values. The length of each successively shorter measuring base is related to the length(s) of the longer one(s) to include amplitude measurements for wavelength values not provided by the longer measuring base(s).

Abstract: The complete renewal of a railway road track, i.e. clearing and screening the ballast, and substituting new ties and rails for the old ones, comprises a continuous sequence of operations forming repeating cycles consisting in removing the old track, clearing and screening the ballast, laying a new track with a single passage of a train comprising, in addition to the apparatus necessary for performing the operations, and to the cars necessary for transporting the rails, ties and hardware accessories, at least one track-laying and removing lift of trucks equipped with gantries and frame trucks.

Abstract: A train assembly for replacement of an old rail track by a new one with long rails comprises a permanently coupled train section including an open-frame wagon with rails carrying gantries for removal of track panels through the open frame and placing new cross-ties. The open-frame wagon has a bogie able to run on the track but retracted during operation and replaced by caterpillar tracks running on the ballast, or by rollers running on the new rails placed temporarily beside the track. The new rails are then brought together and fixed on the newly-placed cross-ties, so that the rear part of the train assembly runs on the new track whereas the front part runs on the old track.