FR3033579A1 - STAMPING MACHINE FOR A BALLAST BED AND METHOD OF JAMMING - Google Patents

Abstract

A stuffing machine for a railroad track, the railway track comprising at least two longitudinal rails (1) extending from upstream to downstream and resting on a plurality of sleepers (2) placed on a ballast bed (3), the machine comprising at least one vibratory tamping arm (4) adapted to be immersed vertically in the depth of the ballast bed (3) between said longitudinal rails (1) and said crosspieces (2) and at least one plating member (5) vibrating in a horizontal plane adapted to be applied to the surface of the ballast bed (3), between said longitudinal rails (1) and said crosspieces (2), close to said vibrating stuffing arm (4) so as to facilitate diving said vibrating tamping arm (4) in the depth of said ballast bed (3).

Description

TECHNICAL FIELD AND PRIOR ART The present invention relates to the field of tamping and compacting the ballast of a railroad track. In known manner, a railway track comprises at least two longitudinal rails connected by transverse cross members resting on a ballast bed adapted to distribute the mechanical forces received by the railway during the circulation of a railway vehicle. Following the passage of railway vehicles on a railway track, it is necessary to correct its geometry periodically. For this purpose, it is known to use a stuffing machine, also called tamper, which allows to position / orient the rails to correct the geometry and freeze this geometry by compacting the ballast under the rail sleepers. A tamping machine comprises vibrating tamping arms, also called tampers, adapted to be immersed in the ballast bed upstream downstream of the cross member whose ballast must be compacted. The stuffing arms are then brought together in order to clamp the ballast under said cross member so as to freeze the position of said cross member. Such a stuffing process effectively compact the ballast under a crossbeam. In addition, such a method makes it possible to achieve a linear compaction speed (corrected number of railway track kilometers per hour) which is high.

One of the drawbacks of such a method is that it excessively solicits the ballast, in particular during the step of dipping the stuffing arms. In practice, after several implementations of the compacting process, the ballast is too deteriorated (breaking of the ballast grains, blunting, etc.) and it is no longer possible to obtain sufficient compaction in order to guarantee the stability of the geometry of the rails. Also, it is necessary to replace the ballast bed, which is a significant cost both as regards the ballast itself as the resources mobilized to allow its replacement (equipment, operators, etc.).

The object of the invention is therefore to overcome these disadvantages by proposing a filling machine of novel design in order to limit the wear of the ballast during its compaction.

GENERAL PRESENTATION OF THE INVENTION To this end, the invention relates to a stuffing machine for a railroad track, the railway track comprising at least two longitudinal rails extending from upstream to downstream and resting on a plurality of sleepers placed on a ballast bed, the machine 10 comprising: - at least one vibratory tamping arm adapted to be immersed vertically in the depth of the ballast bed between said longitudinal rails and said crosspieces and - at least one vibrating plating member in the horizontal plane adapted to be applied to the surface of the ballast bed, between said longitudinal rails and said sleepers, adjacent said vibrating tamping arm so as to facilitate the dive of said vibratory tamping arm into the depth of said ballast bed.

Thanks to the invention, the plating member makes it possible to vibrate the upper part of the ballast bed in order to lower its mechanical strength and thus facilitate the dipping of the stuffing arm which no longer wears and blunts the ballast grains. . Following the action of the plating member, the upper portion of the ballast bed is "liquefied" and can be traversed easily. The life of the ballast is thus improved. The number of 25 ballast grains broken can be halved. Advantageously, as the plating member can be placed between the rails and between the cross members, the plating member can be located closer to the stuffing arm to facilitate its diving.

Preferably, the plating member applies a vertical pressure force of the order of 10 KN so that the vibrations liquefy the upper part of the ballast bed.

Preferably, the filling machine comprises at least two vibrating tamping arms adapted to be immersed vertically in the depth of the ballast bed between said longitudinal rails and said crosspieces, said vibrating tamping arms being aligned laterally, plating is configured to vibrate along said lateral axis in the horizontal plane. Thus, the plating member can act laterally in the dipping areas of the stuffing arms. Advantageously, the plating member does not compact the ballast bed below the cross but facilitates only the dipping of the stuffing arms.

Preferably, the plating member has a flat bottom plating surface for pressing on the surface of the ballast bed. Thus, the ballast grains in contact with the plating member can transmit the vibrations optimally.

According to one aspect of the invention, the plating member has a lower plating surface having an impression defining a plurality of reliefs. Thus, the plating member can trap ballast grains between its reliefs so as to transmit the vibrations optimally in the upper thickness of the ballast bed. Preferably, the reliefs are angular in order to improve blocking of the ballast grains during plating and vibrating. On the other hand, curved reliefs increase the rolling of the ballast grains during vibrations, which accentuates the wear. Preferably, the plating member has a lower mesh surface for trapping ballast grains in its apertures so as to transmit vibrations optimally into the upper thickness of the ballast bed. Preferably, the plating member has a lower plating surface 30 covered with a deformable coating to cooperate with the ballast grains to move them optimally without rolling them relative to the plating member. Thus, the greater thickness of the ballast bed makes it possible to vibrate optimally to offer very little resistance during the dipping of the stuffing arm.

In a preferred manner, the filling machine comprises at least two upstream vibrating tamping arms adapted to be immersed in the ballast bed directly upstream of a cross member, at least two downstream vibrating tamping arms adapted to be immersed in the ballast bed directly downstream of said cross member, a vibrating veneer upstream member adapted to be applied to the surface of the ballast bed between said downstream vibrating tamping arms so as to facilitate the dipping of said downstream stuffing arms into the depth of said ballast bed, and a downstream vibrating plating member adapted to be applied to the surface of the ballast bed between said downstream vibrating tamping arms so as to facilitate diving of said downstream stuffing arms into the depth of said ballast bed. Thus, during compacting of the ballast bed below a cross, the dipping of the upstream and downstream stuffing arms is facilitated by the action of the downstream and upstream plating members 15 which limits the mechanical stresses. Also, all the vibrations of the stuffing arms contribute to compaction. Preferably, said upstream vibrating tamping arms and said downstream vibrating tamping arms are configured to clamp the ballast bed below the crossbar 20 to compact it. The invention also relates to a method of tamping a ballast bed of a railway track by means of a stuffing machine as presented above, the method comprising: a step of applying at least one member vibrating plating in the horizontal plane at the surface of the ballast bed between said longitudinal rails and between two crosspieces so as to reduce the mechanical strength of the upper part of the ballast bed, then - a step of displacement in vertical dive from at least one tamping arm vibrating in the depth of the ballast bed between said vibrating plating member and one of said longitudinal rails. Thus, the application step makes it possible to prepare the ballast bed in order to decrease the mechanical strength of its greater thickness during the vertical dive displacement step. The ballast bed is thus not dull and does not wear prematurely. Preferably, the method comprises a step of vertically plunging at least one tamping arm vibrating into the depth of the ballast bed between said vibrating plating member and each longitudinal rail. Thus, the ballast bed is compacted below the crossbar over its entire length. PRESENTATION OF THE FIGURES The invention will be better understood on reading the description which will follow, given solely by way of example, and referring to the appended drawings in which: FIG. 1 is a schematic representation from above of a implementation of a stuffing machine according to the invention; and Figure 2 is a schematic sectional representation of an embodiment of a plating member. It should be noted that the figures disclose the invention in detail to implement the invention, said figures can of course be used to better define the invention if appropriate. DESCRIPTION OF ONE OR MORE EMBODIMENTS OF IMPLEMENTATION AND IMPLEMENTATION A stuffing machine according to the invention will now be presented to compact a ballast bed beneath a railroad crossing. In known manner, with reference to FIG. 1, a railway track comprises at least two longitudinal rails 1 extending from upstream to downstream and resting on a plurality of crosspieces 2 placed on a ballast bed 3.

The filling machine comprises a main frame adapted to circulate on a railway track and comprises, for this purpose, railway wheels. Nevertheless, it goes without saying that the main chassis could be adapted to travel on a road.

The stuffing machine further comprises a plurality of vibrating tamping arms 4 adapted to be immersed vertically in the depth of the ballast bed 3. In this example, each stuffing arm 4 extends vertically and has a frustoconical shape of in order to improve the vertical progression in the ballast bed 3. A stuffing arm 4 is a wear element which has to be replaced periodically. Each stuffing arm 4 is preferably metallic. To extend their life, titanium pellets can be added to the stuffing arms 4.

In practice, a stuffing machine comprises a plurality of stuffing arms 4 to distribute their action on the ballast bed around a cross member 2 whose position must be fixed. Preferably, as will be presented later, the stuffing machine comprises at least one stuffing arm 4 upstream of the cross member 2 and a stuffing arm 4 downstream of the cross member 2.

Each stuffing arm 4 is connected to the frame of the stuffing machine by a displacement and vibration module which makes it possible, on the one hand, to move a determined stuffing arm 4 to a determined location of the ballast bed 3 and, on the other hand, to vibrate the jamming arm 4 to allow the compacting of grains of the ballast bed 3. It goes without saying that several jamming arms 4 could be connected to the same module of movement and vibration. Such stuffing arms 4 are known to those skilled in the art and will not be presented in more detail. In this exemplary embodiment, with reference to FIG. 1, the stuffing machine further comprises two vibrating plating members 5 in the horizontal plane adapted to be applied to the surface of the ballast bed 3 so as to facilitate the diving of said arms. 4 preferably in the depth of said ballast bed 3. Preferably, each plating member 5 comprises a lower part intended to come into contact with the surface of the ballast bed 3 so as to promote the transmission of vibrations in the upper part. ballast bed 3 to limit friction between the ballast grains. In other words, the mechanical strength of the upper portion of the ballast bed 3 is decreased or "liquefied". Preferably, each plating member 5 is metallic. Each plating member 5 is connected to the frame of the stuffing machine by a displacement and vibration module which makes it possible, on the one hand, to move a specific plating member 5 to a determined location on the ballast bed 3 and, on the other hand, to vibrate the plating member 5 to liquefy the upper part of the ballast bed 3.

With reference to FIG. 1, each plating member 5 is adapted to be vibrated along a lateral axis, that is to say, parallel to the sleepers 2 of the railway track, in order to transmit vibrations in the zones dipping of the stuffing arms 4 as will be presented thereafter.

According to another aspect of the invention, alternatively or cumulatively, each plating member 5 is adapted to be vibrated along a longitudinal axis, that is to say, parallel to the rails of the railway track, or in a circular manner. The lower part of each plating member 5 has a minimum bottom surface area of 15 cm 2 in order to transmit sufficient vibrations into said ballast bed 3. Preferably, the longitudinal length of a plating member 5 is less than 60 cm in order to In this example, each plating member 5 has a rectangular shape 25 but it goes without saying that it could be different, in particular, square, round or oval. More preferably, the lower part of each plating member 5 is full but it goes without saying that it could be partially perforated. According to one aspect of the invention, the lower part of each plating member 5 is in the form of a mesh plate, which makes it possible to trap ballast grains in the openings and thus "integrate" the plating 5 in the upper part of the ballast bed 3 to improve the transmission of vibrations in the upper part of the ballast bed.

When the lower part of each plating member 5 is solid, it may be flat or comprise an impression with a plurality of reliefs 50, preferably angular as illustrated in FIG. 2, in order to be able to trap ballast grains. between reliefs 50 and thus improve the transmission of vibrations.

Preferably, the lower part of each plating member 5, whether it is solid or perforated, is covered with a deformable coating, preferably made of polymer, in order to improve the cooperation between the plating member 5 and the ballast grains by homogeneously distributing the mechanical stresses. In addition, such a deformable coating makes it possible to limit the wear of the ballast grains, which is advantageous. Preferably, the properties of the deformable coating (thickness, material, and.) Can be adjusted to form a low-pass filter or a high-pass filter to allow only a certain range of vibration frequencies at the same time. Thus, the vibration frequencies likely to cause premature wear of the ballast can be eliminated. The stuffing machine also comprises a supply module, thermal, hydraulic, pneumatic or electric, to provide the necessary energy to the various equipment of the stuffing machine (stuffing arm 4, plating member 5, displacement modules and vibration). An exemplary implementation will now be presented with reference to Figure 1 in which the ballast bed 3 below a crossbar 2 must be compacted. For this purpose, an upstream plating member 5 and a downstream plating member 5 are placed between the longitudinal rails 1 of the railway track respectively upstream and downstream of said cross member 2. Preferably, each plating member 5 is placed at equal distance from the longitudinal rails 1 in order to provide sufficient space between the plating member 5 and the longitudinal rails 1.

Then, the plating members 5 are applied against the surface of the ballast bed 3 so that the lower surface of the plating members 5 is in contact with the ballast grains. Each plating member 5 exerts a vertical pressure on the surface of the ballast bed 3. In this exemplary embodiment, the plating members 5 are vibrated in the horizontal plane along a lateral axis, that is, that is, parallel to the cross members 2 to reduce the mechanical strength of the upper part of the ballast bed 3 according to the vibration direction. The use of relief, a grid member and / or a deformable coating makes it possible to improve the transmission of vibrations in the ballast bed 3 in the direction of vibration. Still with reference to FIG. 1, upstream stuffing arms 4 (here two in number) are then moved dive into the ballast bed 3 near the cross member 2 between the upstream plating member 5 and each longitudinal rail. 1. Similarly, downstream stuffing arms 4 are also moved dive into the ballast bed 3 near the cross member 2 between the downstream plating member 5 and each longitudinal rail 1. In this example, arms 4 are also moved dive into the ballast bed 3 outside the longitudinal rails 1 near the cross member 2. Thus, stuffing arms 4 are located on each side of the cross member 2 along the length of the cross member 2 in order to compact the ballast bed 3 on which it rests. During the dive, each stuffing arm 4 is preferably placed in horizontal vibration, more preferably in a rocking motion, to facilitate its insertion into the depth of the ballast bed 3. By way of example, The frequency of vibration is between 35 and 45 Hz. Thanks to the action of the plating members 5, the stuffing arms 4 can penetrate without effort into the depth of the ballast bed 3, which makes it possible to protect the ballast grains 25 and limit their wear. The action of the plating members 5 is even more beneficial that the stuffing arms 4 are located laterally to the plating members 5, that is to say, in the direction of vibration of the plating members 5. As for example, satisfactory results for a plating member 5 have been obtained by applying a vertical load of 10KN for a vibration in a horizontal plane in the lateral direction with an amplitude of 1 cm and a frequency of the order In particular, the number of ballast grains broken during the dipping of the stuffing arms 4 is halved.

Once in the depth of the ballast bed 3, the jamming arms 4 can compact the ballast bed by virtue of their vibrations. Preferably, the stuffing arms 4 move towards the cross member 2 in order to clamp the ballast bed 3 between the upstream stuffing arms 4 and the downstream stuffing arms 4. By way of example, the clamping force 5 is included between 500 and 1000 daN. Thus, after correcting the geometry of the longitudinal rails 1, this geometry can be fixed quickly and conveniently thanks to the stuffing machine according to the invention without unduly damaging the ballast grains.

Advantageously, thanks to the filling machine, the ballast bed 3 can be successively packed below each crosspiece 2. Preferably, the plating member 5 is integrated in a tamping machine. -auto grader. More preferably, the ballast bed 3 can be compacted below several crosspieces 2 simultaneously.

Claims (10)

REVENDICATIONS1. Stuffing machine for a railway track, the railway track having at least two longitudinal rails (1) extending from upstream to downstream and resting on a plurality of sleepers (2) placed on a ballast bed (3), the machine comprising: at least one vibratory tamping arm (4) adapted to be immersed vertically in the depth of the ballast bed (3) between said longitudinal rails (1) and said crosspieces (2) and at least one plating member (5) vibrating in a horizontal plane adapted to be applied to the surface of the ballast bed (3), between said longitudinal rails (1) and said crosspieces (2), close to said vibrating stuffing arm (4) so as to facilitate diving said vibrating tamping arm (4) in the depth of said ballast bed (3). 2. Stuffing machine according to claim 1, wherein, the machine comprising at least two vibrating tamping arms (4) adapted to be immersed vertically in the depth of the ballast bed (3) between said longitudinal rails (1) and said crosspieces (2), said vibrating tamping arms (4) being laterally aligned, the plating member (5) is configured to vibrate along said lateral axis. 3. Stuffing machine according to one of claims 1 to 2, wherein the plating member (5) has a lower flat plating surface. 4. Stuffing machine according to one of claims 1 to 2, wherein the plating member (5) has a lower plating surface having a footprint defining a plurality of reliefs (50), preferably angular. 5. Stuffing machine according to one of claims 1 to 2, wherein the plating member (5) has a lower surface meshed plating. 3033579 12 6. Stuffing machine according to one of claims 1 to 5, wherein the plating member (5) has a lower plating surface covered with a deformable coating. 5 7. Stuffing machine according to one of claims 1 to 6, comprising: at least two upstream vibrating tamping arms (4) adapted to be immersed in the ballast bed (3) directly upstream of a cross member (2). at least two vibrating tamping downstream arms (4) adapted to be immersed in the ballast bed (3) directly downstream of said crossbar (2), a vibrating plating upstream member (5) adapted to be applied to the ballast bed surface (3) between said upstream vibrating tamping arms (4) so as to facilitate the diving of said upstream stuffing arms (4) into the depth of said ballast bed (3), and a downstream vibrating plating member (5) adapted to be applied to the surface of the ballast bed (3) between said downstream vibrating tamping arms (4) so as to facilitate the diving of said downstream stuffing arms (4) into the depth of said ballast bed ( 3). The stuffing machine according to claim 7, wherein said upstream vibrating tamping arms (4) and said downstream vibratory tamping arms (4) are configured to clamp the ballast bed (3) below the cross member (4). 2) in order to compact it. 9. A method of tamping a ballast bed of a railway track by means of a stuffing machine according to one of claims 1 to 8, the method comprising: a step of applying at least one member for plating (5) vibrating in a horizontal plane on the surface of the ballast bed (3) between said longitudinal rails (1) and between two crosspieces (2) so as to reduce the mechanical strength of the upper portion of the ballast bed ( 3), followed by a vertical dive step of at least one vibratory tamping arm (4) in the depth of the ballast bed (3) between said vibrating plating member (4) and one of said longitudinal rails (1). ). 3033579 13 A tamping method according to claim 9, including a step of vertically plunging at least one vibratory tamping arm (4) into the depth of the ballast bed (3) between said vibrating plating member (4) and each longitudinal rail (1). 5