Initial and final methods for laying long rails

Abstract

An initial method for laying a new long rail (22) of a railway track (20) by a construction train (100) traveling in a running direction (F2) is disclosed, the initial method being intended to be implemented during a process for replacing an old rail (21) of the railway track (20), the method comprising a stage (B) during which the new long rail (22) is laid and then fastened to sleepers (23) of the railway track (20) while the construction train (100) is traveling in the running direction (F2), the initial laying method comprising the steps of laying at least one initial portion of the new long rail (221) on the sleepers (23) at at least one end (211') of the old joining rail (211), and at least one The initial laying method includes a step of connecting an end (211') of the old joining rail (211) to at least one end (221') of a first new long rail (221) with a temporary connecting device (30), and a step of welding, for example, by thermite welding, the respective connecting ends of the old joining rail (211) and the first new long rail (221). Prior to the laying step, the initial laying method includes a step of heating or cooling at least one end portion (221') of the first new long rail (221) to a reference temperature, the end portion including the end (221') of the first new long rail (221) to which the end (211') of the old joining rail (211) needs to be connected. A final method for laying new long rails (22) of a railway track (20) by a construction train (100) traveling in a running direction (F2) is also disclosed.

Description

[Technical Field]

[0001] The invention generally relates to the technical field of construction trains, such as construction and replacement trains, which consists in laying down the equipment necessary for the construction of railway tracks or, in the case of replacement, replacing all or part of the materials that make up the track, namely the rails and the fixed structures such as sleepers, as well as the ballast that ensures the retention of the track on its platform, when these materials deteriorate.

[0002] The present invention more particularly relates to a method for initial laying, a method for final laying, and a method for replacing old rails of an already laid railway track with new long rails by means of a construction train, which method starts and / or ends with the above-mentioned initial and / or final laying method for new long rails. [Background technology]

[0003] Builders or operators of rail transport networks periodically need to build new railroad tracks or rebuild existing ones, i.e., replace some of the elements that make up the railroad track, such as the rails and the sleepers that support them, as well as fastening means and other accessories. Most of this replacement is due to wear of the track, but there may also be cases where older models are replaced with more recent models to allow better performance.

[0004] In the most complete cases, such replacements are carried out using a rail train, such as a replacement train, which includes several specialized machines for performing the different replacement operations. A typical operation for the complete replacement of a railway track involves the implementation of a specialized rail train, including machines capable of sequentially performing the following operations: unloading, screening of ballast, and removal of unloaded products by conveyor belts on freight cars for loading and unloading, or by direct jetting onto the bank; replacement of the track to be replaced (rails and sleepers); ballasting and lifting of the track; leveling and shaping of the rails; welding; stress relief; new leveling / shaping; seat adjustment; and edge trimming.

[0005] The constant pursuit of increased safety and running speeds for rail vehicles has led to the design of rails known as "long welded rail" ("LWR"), or "long bar". In the case of rail replacement in particular, the replacement operation consists of replacing the old rail with a new long rail without interfering with other elements of the track (platform, ballast, sleepers). The replacement operation usually involves carrying out the following steps: - supplying new rails of the "LWR" type in the form of prefabricated "long bars" (e.g. 324 meters) in a welding workshop located at a distance from the construction site from basic rails (e.g. three basic rails of 108 meters each) originating from a rail manufacturing plant; - Removal of ties and splitting of old rails, -Removal of old rails, - Positioning and end-to-end alignment of the new rails, thermite welding of the new rails positioned end-to-end to each other, fastening the new rails to the sleepers, - Connection of the new rail to the existing line by thermite welding, stress relief (releasing ties on the new rail, nailing in and re-tightening ties), neutralisation of the rail using rail drift pins if necessary, heating using gas or other methods depending on the temperature at the time of replacement; - Loading and removal of old rails and cleaning of the construction site.

[0006] In tracks with "normal" bars, expansion is absorbed in the area of ​​the rail joints, and the precisely adjusted gap between two consecutive bars allows for slight extension of the rails. Such tracks are therefore relatively insensitive to temperature changes. This does not apply to tracks with long bars or "LWR", since in this case there are no joints between the rails that allow for the absorption of expansion. Clamping the rails onto the sleepers, which in turn are fastened to the ballast, opposes the free movement of the rails under the influence of temperature changes. Since the expansion of the rails is prevented, it is counteracted by an increase in the internal stresses of the rails. When the resistance of the ballast is no longer sufficient to oppose the internal stresses of the rails, the rails will therefore elongate, thus causing a deformation of the shape of the track chassis. Such deformation of the track is obviously very dangerous.

[0007] To significantly reduce the risk of rupture of said rails due to cold weather or deformation due to extreme heat, it is known to carry out an operation to "neutralize" new rails, which makes it possible to fasten the rails in a given state of expansion, at a certain average temperature (for example 25°C), if the neutralization occurs by heating the rails, or with an elongation of the rails corresponding to their expansion at this average temperature, if the neutralization operation is carried out by elongation of the rails.

[0008] All these operations, which are carried out in stages, section by section, rail after rail or long bar after long bar, require considerable time and disruption of running. Of course, the same operations are required during the laying of new track, except for the dismantling of the old ties and removal of the old rails.

[0009] Solutions have long been known that allow for the implementation of rail replacement operations at relatively low speeds, including a step of neutralizing the rails, but that are not suitable for the replacement of rails for laying long welded rails in practice. Other existing solutions require the use of several different rail trains, each for implementing only one part of the replacement operation, which has proven to be expensive. Furthermore, such replacement works are very long and require a lot of labor. Finally, when such solutions propose neutralizing the rails, it has been found that said neutralization does not exist at the end of the new rail connected to the old railway line, or that it is carried out in a conventional manner using separate means. Summary of the Invention

[0010] The present invention aims to overcome all or some of the drawbacks of the prior art by proposing a solution that makes it possible to implement a method for replacing an old rail by a new long rail, in particular at the end of the old rail corresponding to the end of the new rail connected to the old rail and surrounding the part of the rail to be replaced, while ensuring good safety of the laid railway track and providing the shortest possible downtime of the railway track in order to reduce the duration of the works.

[0011] To achieve this, according to a first aspect of the present invention, an initial method for laying new long rails of a railway track by means of a construction train traveling in a running direction is proposed, the initial method being intended to be implemented during a process for replacing old rails of a type of railway track that includes a stage during which a new long rail is laid and then fastened to a fixed structure of the railway track when the construction train is traveling in said running direction, the initial laying method comprising: - laying a first at least one section of a new long rail on a fixing structure at at least one end of the old joint rail; - a temporary end-to-end connection step for connecting an end of the old joining rail to at least one end of the first new long rail by at least one temporary connecting device; - permanently connecting the two connected ends of the old joining rail and the first new long rail, for example by welding, for example by thermite welding, The initial laying method is characterized in that it includes, before the laying step, a step of heating or cooling at least one end portion of the first new long rail to neutralize it to a reference temperature, the end portion including the end of the first new long rail to which the end of the old joining rail needs to be connected.

[0012] "Long rail" refers to a rail also known as "long welded rail" ("LWR") or "long bar." These long welded rails are formed from one or more basic rails of regular length, i.e., "regular bars," which are generally welded together in a welding workshop located some distance from the construction site, thus forming a single, continuous unit. The distinction between long welded rails and rails made of regular bars is therefore very clear in terms of length; long welded rails can extend for hundreds of meters, or indeed for several kilometers. In this context, railway track refers both to tracks laid on ballast or to unballasted tracks laid on other supports (tracks laid on concrete, tracks laid on slabs, etc.). The fixed structures of railway tracks vary in terms of function and include, for example, sleepers, slabs, concrete platforms, etc., depending on the type of railway track.

[0013] Due to this combination of features, this type of method allows the connection between the old and the new railway track with a level of safety guaranteed by neutralizing the rails in a manner corresponding to the rest of the track, in particular in this case in the area of ​​the end portions of the first new long rail, before fixing the rails. Naturally, the initial laying method can be implemented on one line of rails of the railway track or indeed on two parallel lines of rails of the railway track simultaneously.

[0014] According to one embodiment, the initial laying method includes a step of neutralizing, preferably by heating or cooling, the end portion of the old joining rail, which comprises the end of the old joining rail to which the end portion of the first new long rail needs to be connected.

[0015] According to one embodiment, the step of heating or cooling the end portions of the first new long rail to neutralize them to a reference temperature is preceded by a step of neutralizing, preferably by heating or cooling, the end portions of the old joining rail, including the end of the old joining rail to which the end portion of the first new long rail needs to be connected.

[0016] According to one embodiment, the step of heating or cooling the end portion of the old joint rail to neutralize it is carried out by heat transfer or thermal insulation means, preferably including an infrared source for heating said end portion of the old joint rail to a reference temperature.

[0017] According to one embodiment, before the step of connecting the end of the old joining rail to the end of the first new long rail end-to-end by means of a temporary connecting device, a step of cutting the old joining rail is carried out to form the end of the old joining rail to be connected.

[0018] According to one embodiment, the temporary connection device comprises at least one fish plate or rail drift pin. Temporary connection devices such as fish plates or rail drift pins have the function of keeping the rail ends abutted together regardless of changes in the outside temperature, to ensure a perfect joint between the ends. Another function is to maintain the reference length of the old and new rails until the end welding step. The temporary connection device is removed once the rail ends are welded together and the weld has cooled for a predetermined cooling time, approximately 20 minutes. The permanent connection after the temporary connection makes it possible to ensure the rail vehicle can run at a normal speed, while the temporary connection allows for running at a maximum slow speed.

[0019] According to one embodiment, prior to or following the step of temporarily connecting the end of the old joining rail to the end of the first new long rail end-to-end by means of a temporary connecting device, said ends have undergone a preparation step in view of the permanent connecting step, for example a polishing machining step.

[0020] According to another aspect of the invention, it relates to a final method for laying new long rails of a railway track by means of a construction train moving in said direction of travel, the final method being intended to be implemented during a process for replacing old rails of a type of railway track that includes a stage during which a new long rail is laid and then fastened to a fixed structure of the railway track when the construction train is moving in said direction of travel, the final laying method comprising: - laying at least one last section of a new long rail on a fixing structure at at least one end of the old joint rail; - a temporary end-to-end connection step for connecting an end of the last new long rail to at least an end of the old joining rail by means of at least one temporary connecting device; - permanently connecting the two connected ends of the old joint rail and the last new long rail, for example by welding, for example by thermite welding, The final laying method is characterized in that it includes, before the laying step, a step of heating or cooling at least one end portion of the last new long rail to neutralize it to a reference temperature, the end portion including the end of the last new long rail to which the end of the old joining rail needs to be connected.

[0021] According to one embodiment, the final laying method includes a step of neutralizing the end sections of the old joint rail, including the end of the old joint rail to which the end section of the first new long rail needs to be connected, preferably by heating or cooling.

[0022] According to one embodiment, the step of heating or cooling the end portion of the last new long rail to neutralize it to the reference temperature is followed by a step of neutralizing, preferably by heating or cooling, the end portions of the old joining rails, including the ends of the old joining rails to which the end portion of the last new long rail needs to be connected.

[0023] The steps implemented and the means used for this final method are, mutatis mutandis, similar to the initial method. Thus, in the same way as for the end section of the first new long rail, this type of method allows the connection between the old and the new railway track with a level of safety guaranteed by neutralizing the rail in a manner corresponding to the rest of the track, in particular in this case in the region of the end section of the last new long rail, before fixing the rail.

[0024] According to another aspect, the invention also relates to a method for replacing old rails of a railway track of the type including a stage during which new long rails are laid and then fastened to the fixed structure of the railway track by a construction train moving in the direction of travel, the replacement method being characterized by a stage starting with an initial method for laying new long rails as described above and / or ending with a final method for laying new long rails as described above.

[0025] According to one embodiment, the replacement method includes a first stage during which a new long rail is unloaded along the railway track from a transport train of a construction train traveling in a first running direction, and a second stage during which the construction train travels in a second running direction opposite to the first running direction, and during the second stage the new long rail is laid onto fixed structures, such as sleepers of the railway track, and then fastened.

[0026] This type of replacement method can be implemented with one single construction train. Furthermore, the operations performed can be sequenced in an optimized manner. It is no longer necessary to perform all operations simultaneously, i.e., in a sequentially sequenced manner according to a single direction of travel, which has the effect of slowing down the speed of travel on the construction site depending on the most restrictive operation. In fact, when a construction train performs all operations consecutively, a single operation requiring the train to stop is sufficient to limit the progress of the other operations. Proceeding with this type of sequence in two stages and distributing the replacement operations in one direction of travel and then the other has been shown to reduce the construction time for an equal length of rail to be replaced. Finally, all of these operations can be performed during the same temporary interruption of travel, minimizing the duration of this interruption.

[0027] According to one embodiment, the construction train includes a wheelset, e.g., a vehicle mounted on a bogie, and the neutralizing step, such as a heating or cooling neutralizing step, is performed in a zone of the construction train positioned upstream of the first of the construction train's wheelsets relative to the new long rail, with respect to the second direction of travel.

[0028] According to one embodiment, the heating or cooling neutralization step is followed by a step of maintaining and / or correcting a reference temperature of the neutralized portion of the rail, the step of maintaining and / or correcting the reference temperature being preferably carried out in a zone of the construction train positioned at least downstream of the first wheelset relative to the new long rail in the second direction of travel. Preferably, the heat transfer or insulation means comprises an infrared source. During the step of maintaining and / or correcting the reference state, the maintaining means can ensure a correction of the neutralization in addition to the neutralization step, for example, to aim for a reference state not achieved during a previous neutralization step.

[0029] When a new long rail is laid on the fixing structure, a certain distance separates the laying zone of the rail from the fastening zone of the rail to the fixing structure. Such a step of maintaining and / or correcting a reference state, e.g., a reference temperature, downstream in the second running direction and at a distance from the neutralization step makes it possible to ensure that the neutralized new long rail is fixed at a temperature that is maintained at the reference temperature, thereby further reducing the risk of the rail breaking or the track deforming due to the heat difference to which it is exposed.

[0030] The initial method is the initial or operational phase of laying new long rails and dismantling old rails by construction trains to begin replacing a section of track starting from this initial configuration.

[0031] Preferably, the neutralization of the end portions of the old joint rail during the initial laying method is carried out by all or part of the means for maintaining and / or correcting the reference temperature.

[0032] The final method is the final or release stage of the steps in which a new long rail is laid by a construction train and the old rail is dismantled to complete the replacement of a section of railroad track.

[0033] Preferably, the neutralization of the end portions of the old joint rail during the final laying method is carried out entirely or partly by the means for maintaining and / or correcting the reference state. [Brief explanation of the drawings]

[0034] Other features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings.

[0035] [Figure 1] 1 is a schematic diagram of a rail convoy including a construction train according to an embodiment of the present invention; [Figure 2A] FIG. 2 is a schematic detail of FIG. 1; [Figure 2B] FIG. 2 is a schematic detail of FIG. 1; [Figure 2C] FIG. 2 is a schematic detail of FIG. 1; [Figure 2D] FIG. 2 is a schematic detail of FIG. 1; [Figure 3A] 2 is a schematic diagram of a rail train as shown in FIG. 1 during a first stage of a switching method according to the present embodiment; [Figure 3B] 2 is a schematic diagram of a rail train as shown in FIG. 1 during a second stage of a switching method according to the present embodiment; [Figure 4] 3C is a schematic detail of FIG. 3B. [Figure 5A] FIG. 10 is a schematic diagram of an initial step of the second phase of the replacement method according to the present embodiment. [Figure 5B] FIG. 5B is a schematic diagram of an early step of the second phase of the exchange method, after the step of FIG. 5A. [Figure 5C] FIG. 5C is a schematic diagram of an early step of the second stage of the exchange method, after the step of FIG. 5B. [Figure 5D] FIG. 5D is a schematic diagram of an early step of the second stage of the replacement method, after the step of FIG. 5C. [Figure 5E] FIG. 5E is a schematic diagram of an early step of the second phase of the exchange method, after the step of FIG. 5D. [Figure 5F] FIG. 5B is a schematic diagram of an early step of the second phase of the replacement method, after the step of FIG. 5E. [Figure 6A] FIG. 10 is a schematic diagram of the final step of the second stage of the replacement method according to the present embodiment. [Figure 6B] FIG. 6B is a schematic diagram of the final step of the second stage of the exchange method, after the step of FIG. 6A. [Figure 6C] FIG. 6C is a schematic diagram of the final step of the second stage of the exchange method, after the step of FIG. 6B. [Figure 6D] FIG. 6D is a schematic diagram of the final step of the second stage of the exchange method, after the step of FIG. 6C. [Figure 6E] FIG. 6D is a schematic diagram of the final step of the second stage of the exchange method, after the step of FIG. 6D. [Figure 6F]FIG. 6B is a schematic diagram of the final step of the second stage of the exchange method, after the step of FIG. 6E. [Figure 7] 1 is a graph showing the operation of a construction train as it moves along a railroad track.

[0036] For greater clarity, identical or similar elements will be designated by the same reference symbols in all figures. DETAILED DESCRIPTION OF THE INVENTION

[0037] 1, 2A, 2B, 2C, and 2D are schematic diagrams of a rail convoy 10 comprising a construction train 100 according to an embodiment of the present invention. The construction train 100 comprises an engine 110 at the front of the train, followed by a transport train 120, in this case directly coupled to the engine 110. The transport train 120 is designed to ensure the transport of new long rails 22 transported over a construction zone Z0 and, preferably, also to store old rails 21 removed from this same construction zone Z0 when the new long rails 22 are laid. The construction train 100 comprises a construction train 130 coupled to the rear of the transport train 120. The construction train 130 is illustrated in a variant comprising three construction vehicles 131, 132, and 133 coupled in series, in particular a first construction vehicle 131, a second construction vehicle 132, and a third construction vehicle 133. This is a variable configuration, i.e., the configuration of the wagons may change from point to point, for example when passing through a work yard, but once specified, generally does not change further for a particular construction site, except when passing through a work yard.

[0038] It should be noted that the "old" rails extend in the manner of the already laid rails that are already present on the track to be replaced, and the new rails extend in the manner of the rails that replace said already laid rails. These terms do not refer to wear or aging of the rails themselves.

[0039] The rail train 10 is equipped with a welding machine 140, which in this case is a railway machine that can be detachably coupled to the end of the construction train 100, in particular to the end of the construction train 130, here with respect to the first direction of travel F1. Such coupling makes it possible to move the rail train up to the construction zone Z0. The welding machine 140 is intended to be detached from the construction train 100 upon arrival in the vicinity of the construction zone Z0, as shown in FIG. 1, so that it can travel independently from the construction train 100, preferably at a distance from the construction train 100. Its use will be better understood by reading the exchange method described below.

[0040] 3A and 3B are schematic diagrams of the rail train 10 in a first phase A and a second phase B, respectively, of the replacement of the railroad track 20, which is the replacement of the old rails 21 of the railroad track 20 with new long rails 22. The method for replacing the old rails 21 of the railroad track 20 with the new long rails 22 generally comprises: a first stage A during which new long rails 22 are unloaded along the railway track 20 from the transport train 120 of the construction train 100 traveling in a first direction of travel F1; a second stage B during which the construction train travels on the reverse path, i.e. in a second running direction F2 opposite to the first running direction F1, and new long rails 22 are laid and then fastened onto the fixed structures 23 of the railway track 20, in this case the sleepers 23.

[0041] In other words, the construction train 100 moves on the railway track 20 in two stages, leaving A and returning B, during which the construction train 100 implements various steps, and the combination of these two stages A and B makes it possible to ensure the replacement of the railway track 20.

[0042] During the first phase A, new long rails 22 are continuously unloaded from the transport train 120 of the construction train 100 along the railway line 20, while the construction train moves forward according to a first running direction F1 driven by the engine 110. The engine 110 may or may not optionally provide traction assistance for the construction train 100, which is equipped with its own advancement system, in particular by means of a distributed drive wheel set. Delivery to the construction site can therefore be carried out according to two variants: using a self-propelled machine specific to the construction train, or by being towed by a locomotive. At the construction site, the self-propelled machine can also be assisted by traction ensured by the locomotive.

[0043] Depending on the desired configuration, these new long rails 22 can be unloaded outside the railway track 20, alongside the old rails 21 they are replacing, or in the center of the railway track 20. Once the first phase A is finished, this results in the alignment of the new long rails, which are successively laid and positioned along and near the railway track 20. A step of placement on supports, such as roller supports, is preferably carried out by one of the vehicles of the construction train 130 before the new long rails are unloaded, so that the new long rails rest on the ground, on these roller supports, and not directly on the ground or ballast. A station 107' designed to ensure the laying or placement of the roller supports is located upstream of the position where the new long rails 22 are unloaded, with respect to the first running direction F1. In this embodiment, the construction station 107' ensuring the positioning of the roller supports is implemented by the first vehicle 131 of the construction train, in front of the second vehicle 132 in the area where loading and unloading is ensured, relative to the first travel direction F1.

[0044] Concurrent with the unloading of the new long rails 22 along the railroad track 20, still during the first phase A, each end of the unloaded new long rails 22 undergoes a preparation step for a permanent connection, e.g., a welding step. Such preparation step includes, for example, a grinding machining step. The preparation step for welding is performed by a welding preparation post 116 carried by a welding machine 140. In this example, the welding machine 140 is a railway machine. In certain configurations, the welding machine may also be a welding rail truck or a welding rail excavator. The welding machine 140 travels independently of the construction train 100 in a first direction of travel F1 behind the construction train 100. Thus, during the first phase A, the welding machine 140 travels in generally the same direction F1 as the construction train 100, at a distance d behind the construction train 100, which distance is variable during the first phase A. In this way, the construction train 100 proceeds at a virtually continuous and uniform speed to unload the new long rails 22, with several short pauses to guide the new long rails 22 towards the train's laying zone, said pauses in the construction progress indicating stage A3 (see Figure 7), while the welding machine 140 proceeds in an orderly manner at different speeds, alternating between static phases in which the end of the new long rail 22 is prepared for welding and dynamic phases in which it proceeds along the railway track 20 to reach the subsequent end.

[0045] During the second phase B, the construction train moves according to a second direction of travel F2 opposite to the first direction of travel F1, and therefore travels a reverse path. The rail convoy 10, including the locomotive 110 (optional if not used as traction aid during construction), then the transport train 120 and the construction train 130, then travel in reverse order, successively from front to rear relative to the first direction of travel F1, with the construction train 130 positioned ahead of the construction train 100 in relation to this second direction of travel F2. The welding machine 140, which traveled independently at a distance behind the construction train during the first phase A, still travels independently at a distance from the construction train 100 during the second phase B, but this time ahead of it in relation to said second direction of travel F2.

[0046] The operations are performed substantially simultaneously during the second phase B above.

[0047] The old rails 21 of the section of railroad track to be replaced are dismantled by the construction train 100 and then preferably loaded onto the transport train 120 of the construction train 100. The old rails 21 are stored in separate sections, which are interlocked at regular intervals while they are being loaded onto the transport train 120 of the construction train 100. In this way, the transport train 120 can be used to store both the new long rails 22 and the old rails 21. Another possible alternative is for the old rails 21 to be removed along the railroad track 20 itself, in particular from their position on the sleepers 23. The transport train 120 is equipped with handling devices 121, such as handling frames, that allow certain operations to be performed reliably, such as cutting the old rails 21 or gripping the rails 21, 22. Alternatively, or in addition, these operations can also be performed entirely or partially manually. The loading path of the old rails 21 preferably follows the reverse path of the loading and unloading path of the new rails 22. In this way, the number of devices present on the second vehicle 132 of the construction train 130 is limited.

[0048] Therefore, during the second stage, a welding machine 140 traveling ahead of the construction train 100 and in the same direction of travel F2 as the construction train is equipped with welding means 115 and also performs end-to-end welding, preferably electric welding, of the new long rail 22. The welding machine 140 works at a sufficient distance from the construction train 100 to allow the electric welds to cool before laying the new long rail 22. A cooling time of, for example, about 20 minutes can therefore be ensured.

[0049] The laying of the new long rails 22 on the sleepers 23 of the railway track 20 is ensured by the construction train 100 in the area of ​​the laying zone Z1, located downstream of the welding machine 140. This laying operation consists in particular, but not exclusively, of moving the new long rails 22 arranged along the railway track 20 in order to install them on the sleepers 23 in the same place where the old rails 21 were previously dismantled; said dismantling takes place in a demolition zone Z6, located upstream relative to the laying zone Z1. The dismantling of the old rails 21 and the laying of the new long rails 22 are carried out in parallel and therefore proceed in a synchronized manner. The same vehicle 132 of the construction train 130 primarily implements the dismantling and laying steps, as the laying zone Z1 and the demolition zone Z6 are located perpendicular to the same vehicle 132 of the construction train 130, and said steps are implemented by the same second vehicle 132. In this way, the discontinuity in the railway track 20 caused by the demolition of the old rail 21 and the laying of the new long rail 22 is spanned by the same vehicle 132 carried by a wheelset such as an upstream bogie 101 moving on the old rail 21 relative to the second running direction F2, and a wheelset such as a downstream bogie 101 moving on the new long rail 22 positioned on the sleepers 23. Said downstream bogie 101 of the vehicle 132 performing these two steps constitutes the first of the bogies 101 of the construction train 100 relative to the new long rail 22, relative to the second running direction F2.

[0050] To enable fastening of the rail in a given expanded reference state, a step of neutralizing the new long rail 22 by heating or cooling it to a reference temperature is carried out with the portions 24. During said neutralization step, each of the portions 24 of the new long rail 22 located in zone Z2 (see FIG. 4 ) is heated or cooled to a reference temperature by a main neutralization means 111 located in the same zone Z2 before being laid on the sleepers 23 of the railway track 20. The main neutralization means 111 preferably comprises heating means such as induction heating means. Preferably, the main neutralization means 111 includes cooling means, for example a device for projecting a flow of a liquid such as water, or a flow of gas, ideally air, optionally compressed, such as dry ice.

[0051] The neutralization zone Z2 is located upstream of the first of the wheel sets, in particular the bogies 101 in this case, of the construction train 100 relative to the new long rail 22 in the second running direction F2.

[0052] To avoid an excessively significant temperature difference between the reference temperature and the temperature of the rail at the time it is fastened to the sleepers 23, the neutralization step of heating or cooling is followed by a step of maintaining and / or correcting the reference temperature of the neutralized portion of the rail 24 by heat transfer or insulation. Preferably, the heat transfer or insulation means comprises an infrared source.

[0053] The steps of maintaining and / or correcting the reference temperature are carried out in a zone Z3 of the construction train 100, which is located at least downstream of the neutralization zone Z2 and downstream of the first of the bogies 101 with respect to the new long rail 22, with respect to the second running direction F2. In the variant shown in FIG. 4, the zone Z3 continues downstream of the second bogie with respect to the new rail. The new long rail 22 is then fastened to the sleepers 23 by ties in a zone Z4 of the construction train 100, which is located directly downstream of the construction train zone Z3, where the steps of maintaining and / or correcting the reference temperature are carried out. The steps of maintaining and / or correcting the reference state, i.e. the reference temperature, are carried out by at least a reference temperature maintaining and / or correcting means 113, which is located in the area of ​​the same zone Z3.

[0054] Naturally, an additional step of maintaining and / or correcting the reference temperature of the neutralized rail section 24 by heat transfer or insulation can be carried out, for example, in another upstream reference temperature maintaining and / or correcting zone Z5 by an additional reference temperature maintaining and / or correcting means 112 upstream of the first bogie 101 and downstream of the neutralization zone Z2 relative to the new long rail 22 (see FIG. 4). In fact, a notable distance, in this embodiment about 8 m, separates the first main neutralization means 111 of the bogie 101 relative to the new long rail 22, which justifies the interest in such an additional upstream reference temperature maintaining and / or correcting device 112. Naturally, other additional holding means for the reference temperature, for example an additional holding and / or correction means 114 for the reference temperature positioned between means 113 and 112, can be used in the area of ​​the first and second bogies 101 for the new long rail 22, the first of the bogies 101 for the new long rail 22 forming the downstream bogie of the second vehicle 132 and the second of the bogies 101 for the new long rail 22 forming the upstream bogie of the first vehicle 131 preceding it in the second running direction F2.

[0055] Ideally, the steps of maintaining and / or correcting the reference step are carried out over the entire section of the rail located between its neutralization and its fastening, with the fastening of the tie being directly downstream of the maintaining and / or correcting to the reference state. In practice, the presence of any equipment or construction stations, for example required for laying the ties 107 before fastening them (screws and / or clips) by the construction station 108, ensures that the distance separating zone Z4 of the construction train, in which the steps of fastening the new long rail are carried out, from zone Z3 of the construction train, in which the steps of maintaining and / or correcting the reference state are carried out, is less than 7 m.

[0056] During the second phase B, initial and final phases must be implemented to start and finish the laying of the new long rails 22, simultaneously with the demolition of the old rails 21 to the existing railway line, which must ensure the connection of the new long rails 22.

[0057] To achieve this, the second phase B includes an initial phase, which is illustrated in detail in Figures 5A, 5B, 5C, 5D, 5E, and 5F. In these figures, for simplicity's sake, only the first vehicle 131 and the second vehicle 132 of the construction train 130 are illustrated. In the initial configuration, the old rail 21 extends continuously and is fastened to the sleepers 23 by ties (not shown), while the new long rail 22 is laid along the railway track (see Figure 5A). The initial phase corresponds to the operation of laying the new long rail 22 by the construction train 100 and dismantling the old rail 21 in order to start the replacement starting from this initial configuration. The initial phase particularly, but not exclusively, includes, for each of two parallel rails in the same area of ​​the railway track 20, preferably, but not exclusively, - a step of dismantling the ties fastening the old rail in the vicinity and downstream of the rail to be replaced, i.e. in the section located downstream of the end 211' of the old joint rail 211, to which the first end section 221' of the new long rail 221 must be connected in relation to the second running direction F2 (see FIG. 5B), said step of dismantling said ties being implemented by dismantling means 102 preferably located in the area of ​​the third upstream vehicle 133 of the construction train 130 in said running direction F2, when said tie dismantling step may also be used or implemented upstream of the vehicle 132 implementing the neutralization step; a heating or cooling step for neutralizing the end 211' of the old joining rail 211 downstream of the end 211' of the old joining rail 211 to which the end 221' of the first new long rail 221 must be connected, in the second running direction F2 (see FIG. 5B ), the end 211' including the end 211' of the old joining rail 211 to which the end 221' of the first new long rail 221 must be connected, said heating or cooling step being preferably not carried out by a neutralization heating or cooling means 111 but by reference temperature maintenance and / or correction means 113, 114, 112, said heat transfer or heat insulation means being partly (112) carried by a second vehicle 132 coupled to the front of the first vehicle 131 and positioned downstream of the construction train 130 in said running direction F2, - cutting the old rail 21, in particular the old joint rail 211 (see FIG. 5C), thus creating a discontinuity in the railway track 20 at the position where this discontinuity will be crossed by the vehicle 132 which, as the train travels in the direction of travel F2, carries out neutralization heating or cooling, dismantling of the old rail 21 and laying of new long rails 22; a heating or cooling step to neutralize the ends 221' of the first new rung of rail 221, including the ends 221' to which the ends 211' of the old joining rail 211 must be connected; - after laying at least a portion of at least the first new long rail 221 on the sleepers 23 at the end 211' of the old connecting rail 211, temporarily connecting the end 211' of the old connecting rail 211 end-to-end to the end 221' of the first new long rail 221 by means of a temporary connecting device 30 (see FIG. 5D), such as a fishplate or a rail drift pin, which ensures the passage of the bogie 101 and makes it possible to keep the end-to-end connection in an ideally neutral position despite possible changes in the outside temperature; a step of permanent connection, e.g. welding, preferably thermite welding, of the two connected ends 211′, 221′ when the construction train 100 has passed the temporary connection device 30, followed by a step of removing the temporary connection device 30.

[0058] In certain configurations, heating or cooling of the end 211' of the old joining rail 211 upstream of the end 211' of the old joining rail 211 before the rail is cut can be ensured by at least one neutralizing heating or cooling means 111 and / or all or part of the reference temperature maintenance and / or correction means 112, 113, 114. In this latter case, the neutralizing heating or cooling means 111 preferably operates only from the step of neutralizing the first end 221' of the new long rail 221 to the reference temperature. The advantage of using all or only part of the reference temperature maintenance and / or correction means 112, 113, 114 is that in this location, the old joining rail 211 is laid on sleepers 23, and the use of a neutralizing means 111, such as induction heating, could damage the ties of the old rail, which are also metal like the rail. The heating for the maintenance and / or correction 112, 113, 114 is less powerful than the induction heating 111, preventing damage to the ties. This is easier to implement than using power variation means, in particular induction heating means, for the neutralization means 111, which would make the device more expensive and more complex. The heating or cooling of the end 211' of the old joining rail 211 is preferably carried out over a distance longer than the zone where the tie is broken (see Figure 5B).

[0059] The second phase B also includes a final phase corresponding to the release of the steps of laying new long rails 22 and dismantling the old rails 21 by the construction train 100 to complete the replacement. Said final phase is illustrated in detail in Figures 6A, 6B, 6C, 6D, 6E and 6F, and in particular, but not exclusively, for each of two parallel rails in the same area of ​​the railway track 20: a heating or cooling step to neutralize the end 222′ of the last of the new long rails 222 to a reference temperature, including the end 222′ of the last new long rail 222 to which the old rail 20 must be connected (see FIG. 6B ); - cutting the old rail 21 to define the end 212' of the old joining rail 212 (see FIG. 6C), - temporarily connecting the end 222' of the last new long rail 222 to the end 212' of the corresponding old joining rail 212 by means of at least one temporary connecting device 30, such as a fishplate or a rail drift pin (see FIG. 6D), which allows the rail to freely extend but not retract in case of heating use, or to freely retract but not extend in case of cooling use, thus maintaining a neutral position despite possible changes in the outside temperature; a heating or cooling step for neutralizing the end 212' of the old joining rail 212, located upstream of the end 212' of the old joining rail 212 to which the end 222' of the last new long rail 222 must be connected, relative to the second running direction F2 (see FIG. 6D), the end 212' of the old joining rail 212 including the end 212' of the old joining rail 212 to which the end of the last new long rail 222 must be connected, said heating or cooling step being preferably not carried out by the neutralization heating or cooling means 111 but by the reference temperature maintenance and / or correction means 113, 114, 112, and the heating or cooling of the end 212' of the old joining rail 212 is preferably carried out over a distance longer than the zone where the ties are to be broken (see FIG. 6E); a step of permanently connecting, e.g., welding, e.g., thermite welding, of the two connected ends 212′, 222′ when the construction train 100 has passed the temporary connecting device 30, followed by a step of removing the temporary connecting device 30.

[0060] During the entire travel of the construction train 130, according to the second direction of travel F2, a construction station 102 arranged in front of the construction train 130 in the direction of travel F2, in this case upstream of the third vehicle 133, is designed to remove the rail ties fastening the rails to the sleepers 23 so that the section P1 of the railway track 20 to be separated is no longer fastened by the ties; a work station 103 carried by a third vehicle 133 and arranged downstream of the work station 102 for removing the ties, designed to collect the removed ties; the work station 104, carried by the second vehicle 132 and positioned downstream of the work station 103 for collecting ties, is designed to dismantle the old tie pads, generally made of rubber and positioned between the sleepers and the bottom of the rail, said tie pads having the role of damping part of the vibrations and allowing the longitudinal advancement of the rail without damaging the sleepers 23; a second vehicle 132 carrying a second tie pad dismantling station 105 downstream of the station 104 for dismantling the old tie pads and upstream of the neutralization means 111, the station 105 being designed to place new tie pads on the sleepers 23 on which the new long rails 22 will rest; a work station 106, carried by a first vehicle 131 and arranged downstream of the reference temperature maintenance and / or correction means 113 located in the area of ​​zone Z3, designed to collect the old Thai pads dismantled by the work station 104; a construction station 107 carried by a first vehicle 131 and located downstream of the construction station 106 for collecting old Thai pads and designed to place the Thai; - construction station 108, carried by the first vehicle 131 and positioned downstream of the tie-placing construction station 107, designed to fasten the rail tie and thus fasten said rail to the sleeper 23, so that the attached portion P2 of the railway track 20 is blocked by the tie.

[0061] In this way, the new rail is neutralized in a disconnected state. Naturally, these construction stations can be substantially shifted. As will be explained, in a configuration with a third freight car 133, it is this freight car 133 that can ensure the removal of the rail ties. The step of collecting the ties is then preferably carried out immediately after their removal. The new long rail 22 is then attached either using new ties or using old ties that have been previously removed and then collected, in order to ensure the recycling of the ties, if the condition of the ties allows this.

[0062] It should be noted that "work station" means any work station capable of receiving personnel to perform manual tasks, and / or any device intended to perform these tasks automatically or semi-automatically.

[0063] Furthermore, during said second phase B, the removal of the ties, and therefore the subsequent blocking of the ties, is carried out starting from the downstream part of the end 211' of the old connecting rail 211, including the end 211' to which the end 221' of the first new long rail 221 must be connected, and extending, in relation to the second running direction F2, to the upstream part of the end 212' of the old connecting rail 212, including the end 212' to which the end 222' of the last new long rail 222 must be connected. In this way, the laying of the new long rail is carried out at the reference temperature, which is then followed by operations aimed at fastening the new long rail in accordance with the predetermined reference temperature.

[0064] 7 is a graph illustrating the work of a rail train 10, in particular its progress along the railway line 20, where the x-axis indicates the passage of time during construction and the y-axis indicates the position relative to the railway line 20. Here, a first curve C100, which is the upper curve, corresponds to the progress of the construction train 100, and a second curve C140 below the curve C100 corresponds to the progress of a rail car 140 traveling at a distance d independent of the construction train 100.

[0065] During the first phase A, the construction train 100 moves from a start position X0 to an end position X1 along the railway track 20. During this movement according to a first running direction F1, the construction train 100 alternates between dynamic steps A1 during which new long rails 22 are unloaded along the railway track 20, and static steps A3 during which each new long rail points to a stage at which it engages in the construction train's guide tunnel to ensure accurate unloading of these new long rails 22 along the railway track 20.

[0066] In parallel with the progress of the construction train 100, the rail vehicle 140 advances stepwise in a first travel direction F1, alternating between a static step A2 of preparing for welding and a dynamic step A4 of moving from the abutting end of one of the two new long rails to the abutting end of the other.

[0067] The first phase A is followed by a second phase B, during which the construction train 100 moves along the railway track 20 from the end position X1 to the start position X0. During this movement in the second running direction F2, the construction train 100 alternates between a dynamic step B3 in which the old rails 21 are loaded onto the transport wagons 120 and a static step B5 indicating a stage during which the old rails 21 are cut during their loading, so that the old rails 21 can be stored in multiple basic sections on the transport train 120.

[0068] In this type of embodiment, tests have shown that the construction train 100 can proceed according to a construction radius of 250 m and a gradient of 40%, while proceeding at a speed of 2500 m / h during the first stage A and at a speed of 600 m / h during the second stage B. Such a method according to the invention also offers the advantage that it can be carried out, if necessary, while leaving the adjacent railway track as free as possible so that it can travel on the adjacent railway track in complete safety.

[0069] In parallel with the progress of the construction train 100 during the second phase B, the rail car 140 advances in stages, following the second travel direction F2, alternating between a welding step B2 and a movement step B4 from the abutting end of one of the two new long rails to the other. Steps B6 and B7 indicate the continuation of the progress of the welding machine 140 and the construction train 100, respectively, and their movement beyond the starting position X0 to ensure the welding between the two connected ends 212′, 222′ at the end of the construction. The initial stage B1 (FIGS. 5A-5F) and the final stage B4 (FIGS. 6A-6F) of the second phase B are shown by stages, which are simplified given the very low movement speed of the construction train 100 during these two phases A and B. Furthermore, such a method allows for easy and relatively fast implementation of electric welding operations for LWR rails, dismantling and reinstalling rail ties, and rail neutralization.

[0070] Of course, the present invention has been described above by way of example, and it will be understood that those skilled in the art can implement different variants of the invention without in any way departing from the scope of the invention.

[0071] For example, the configuration of the construction train may be different. The construction train may have only two freight cars, as shown in Figures 5 and 6, or three freight cars, as shown in Figures 1, 2, 3 and 4. More precisely, it is possible to design the construction train so that the construction is carried out without the third construction vehicle 133 of the construction train 130. In such a design, the old track ties can be dismantled using hand tools upstream of the rail cars, with respect to the second direction of travel F2.

[0072] Furthermore, the rails can be replaced two by two in parallel, so as to replace the entire railway line during the operation, and / or consecutively along only one side of the railway line, so as to replace the rails of a single line. In practice, it can be envisaged that only consecutive rails on one side of the railway line are replaced, which may be of interest in sections of the railway line, such as curved sections. In other words, the initial and / or final laying methods may be carried out simultaneously on one line of rails of the railway line, or indeed on two parallel lines of rails of the railway line, with respect to the replacement.

[0073] In an alternative or additional design, neutralization may be achieved other than by heating or cooling, but by mechanical stresses that may cause the portions of the rail to elongate in a manner that corresponds to their expansion at said reference temperature. The reference state therefore corresponds to an expansion state given as a reference, which itself corresponds to the state of the portions of the rail when exposed to said reference temperature.

[0074] It may also be envisioned that the first stage A and the second stage B are performed at intervals in time, with the first stage A being performed one night and the second stage B being performed the following night.

[0075] For the dismantling of old rails, the old rails can also be unloaded along the railway line from their location on the sleepers instead of being loaded onto a transport train.

[0076] The bogie may also be formed by any type of wheel set.

[0077] Such rail trains are particularly interesting in that they allow the replacement of railway tracks with the shortest possible immobilization of the railway track in order to reduce the duration of the works while ensuring good safety of the laid railway track. Of course, it is also possible to use this type of rail train for operations that do not involve all steps. Rail trains can be used simply to transport and load / unload new long rails along the railway track from a transport train, either on the outside or inside of the railway track, with the optional operations of welding and placement of roller supports.

[0078] It is emphasized that all features that one skilled in the art will follow from this specification, the drawings and the appended claims, both individually and in any combination, even if specifically described only in connection with other particular features, can be combined with other features or groups of features disclosed in this specification, unless expressly excluded or the technical circumstances make such combination impossible or meaningless.

Claims

1. 1. A method for laying new long rails (22) of a railway track (20) by means of a construction train (100) traveling in a running direction (F2), the method being carried out during a process for replacing old rails (21) of the railway track (20), the process comprising a step (B) during which the new long rails (22) are laid and then fastened to a fixed structure (23) of the railway track (20) when the construction train (100) is traveling in the running direction (F2), the method comprising: - a laying step of laying at least a first part of said new long rail (221) on said fixing structure (23) at at least one end (211') of the old joint rail (211); - a temporary end-to-end connection step for connecting said end (211') of said old joining rail (211) to at least one end (221') of said first new long rail (221) by means of at least one temporary connecting device (30); - permanent connection of the two connected ends of the old joining rail (211) and the first new long rail (221), The method comprises, before the laying step, a step of heating or cooling at least one end portion (221') of the first new long rail (221) to neutralize it to a reference temperature, the end portion comprising the end (221') of the first new long rail (221) to which the end (211') of the old joining rail (211) needs to be connected.

2. A method as described in claim 1, characterized in that it includes a step of neutralizing the end portion of the old joining rail (211), including the end (211') of the old joining rail (211) to which the end portion (221') of the first new long rail needs to be connected.

3. 3. A method according to claim 1 or 2, characterized in that the step of heating or cooling the end portion of the old joint rail to neutralize it is carried out by heat transfer or thermal insulation means.

4. 4. The method according to claim 1, wherein before the step of temporarily connecting the end (211') of the old joining rail (211) end-to-end to the end (221') of the first new long rail (221) by means of the temporary connecting device (30), a step of cutting the old joining rail (211) is carried out to form the end (211') of the old joining rail (211) to be connected.

5. The method according to any one of claims 1 to 4, characterized in that the temporary connection device (30) comprises at least one fishplate or rail drift pin.

6. 6. The method according to claim 1, wherein prior to or following the step of temporarily connecting the end (211') of the old joining rail (211) to the end (221') of the first new long rail (221) end-to-end by means of the temporary connecting device (30), the ends (211', 221') undergo a preparation step taking into account the permanent connecting step.

7. 1. A method for laying new long rails (22) of a railway track (20) by means of a construction train (100) traveling in a running direction (F2), the method being carried out during a process for replacing old rails (21) of the railway track (20), the process comprising a step (B) during which the new long rails (22) are laid and then fastened to a fixed structure (23) of the railway track (20) when the construction train (100) is traveling in the running direction (F2), the method comprising: - a laying step of laying at least a final portion of the new long rail (222) on the fixing structure (23) at at least one end (212') of the old joint rail (212); - a temporary end-to-end connection step for connecting an end (222') of said last new long rail (222) to at least said end (212') of said old joining rail (212) by means of at least one temporary connecting device (30); - permanent connection of the two connected ends of the old joining rail (212) and the last new long rail (222), The method comprises, before the laying step, a step of heating or cooling at least one end portion (222') of the last new long rail (222) to neutralize it to a reference temperature, the end portion including the end (222') of the last new long rail (222) to which the end (212') of the old joining rail (212) needs to be connected.

8. 8. The method according to claim 7, characterized in that the method includes a step of neutralizing end portions (212′) of the old joining rails (212), including the end (212′) of the old joining rails to which the end portion of the last new long rail (222) needs to be connected.

9. The method according to claim 8, - an initial laying step of laying at least a first part of said new long rail (221) on said fixed structure (23) at at least one end (211') of the old joint rail (211); - a temporary end-to-end connection step for connecting said end (211') of said old joining rail (211) to at least one end (221') of said first new long rail (221) by means of at least one temporary connecting device (30); - permanent connection of the two connected ends of the old joining rail (211) and the first new long rail (221), 9. The method according to claim 7, wherein the method comprises, before the first laying step, a step of heating or cooling at least one end portion (221′) of the first new long rail (221) to neutralize it to a reference temperature, the end portion comprising the end (221′) of the first new long rail (221) to which the end (211′) of the old joining rail (211) needs to be connected.

Images