CN115768949A

CN115768949A - Rail member

Info

Publication number: CN115768949A
Application number: CN202180048253.4A
Authority: CN
Inventors: A·奥古斯汀; H·罗伊; E·斯托克; H·奥斯伯格
Original assignee: Vai Switch Technology Celtveger Co ltd; Vai Railway System Co ltd; Getzner Werkstoffe Holding GmbH
Current assignee: Vai Switch Technology Celtveger Co ltd; Vai Railway System Co ltd; Getzner Werkstoffe Holding GmbH
Priority date: 2020-07-08
Filing date: 2021-06-29
Publication date: 2023-03-07
Also published as: TWI788908B; KR20230037039A; ES2932154T3; TW202217115A; AR122888A1; EP3936662B1; PT3936662T; HUE060877T2; EP3936662A1; WO2022009020A1

Abstract

In the case of a rail component (1), in particular a switch fork (1), comprising a running surface for the wheels of a rail vehicle, a lower side (2) opposite the running surface, and at least one hollow space (3) which is open toward the lower side (2), a damping means (8) is accommodated in the hollow space (3), the damping means (8) being formed from a composite material which is arranged in the hollow space (3) and comprises an elastomer foam material and a plurality of block-shaped additives distributed therein.

Description

Rail member

Technical Field

The invention relates to a rail component, in particular a switch fork, comprising a rolling surface for the wheels of a rail vehicle, a lower side opposite the rolling surface, and at least one hollow space which is open toward the lower side, wherein a damping means is accommodated in the hollow space. The invention also relates to a method for manufacturing a rail part.

Background

When traveling on a rail by rail vehicles, such as trains or streetcars (Stra β enbahn), sound waves are emitted according to the speed, which are perceived by tram or train passengers, in particular by inhabitants in the vicinity of the respective guide rail line, as unpleasant and disturbing. In particular, when the rail vehicle travels through the existing turnout junction gap, the turnout junction emits a greater degree of noise and vibration than the remaining extensions of the rail line. The switch fork in this case behaves as a vibrating and resonant body due to its structure (because it has at least one hollow space open to the underside at the underside opposite the rolling surface for the wheels of the rail vehicle).

Therefore, a series of attempts have been made to influence the vibration and resonance behaviour of the rail parts, and in particular of the turnout frog, in the sense of reducing the noise emissions by damping.

For example, EP 3 190 229 A1 discloses a railway profile configured to reduce vibrations and noise, wherein a rail part is disclosed which has a plurality of hollow spaces at its underside, wherein in each case one special mass damper is used in one hollow space, which damper is tuned to the damping of a specific frequency and is cast here in the simplest case. In EP 3 190 229 A1, the mass dampers are each disclosed as solid blocks made of steel and the steel blocks must be placed in the hollow space at a distance from the body of the rail part in order to be able to vibrate freely. The solution according to EP 3 190 229 A1 can be seen as complex and expensive as a whole.

Disclosure of Invention

The object of the present invention is therefore to provide a rail part which can be produced simply and cost-effectively and at the same time is effectively damped in order to reduce the noise emission when driving over the rail part.

The object is achieved according to the invention in that the damping means are formed by a composite material arranged in the hollow space, which composite material comprises an elastomer foam material and a plurality of block-shaped additives distributed in the elastomer foam material. In contrast to the prior art, the costly installation of specially dimensioned damping elements in the form of mass dampers in the hollow spaces of the rail parts is eliminated in the present invention, but the damping is based on the total mass of the elastomer foam material with the pourable additive or additives and the damping properties of the elastomer in the hollow spaces. The additive is massive and can therefore be entrained by the mass of the foam material (or mass) before foaming, in order to produce the composite material in the hollow space. In this way, the additive is coupled to the rail part in an oscillating manner and, due to its relative irregularity, leads to vibration damping of the broad band when driving through the rail part according to the invention and thus to a significant reduction in noise emission in a simple and particularly cost-effective manner. In this way, an innovative material and corresponding rail part are provided which exhibit an optimum solution for the application in terms of damping, stiffness and density properties.

Preferably, the rail part comprises two, three or more hollow spaces open towards the underside, in which hollow spaces a damping means of the type according to the invention is accommodated in each case. The hollow spaces here preferably extend in the longitudinal direction of the guide rail and are arranged next to one another.

Preferably, the foam material is configured as a foam material of the mixing chamber. Such foams offer a high mechanical loss factor and good recovery capability and are therefore particularly suitable for damping acoustic vibrations.

According to a preferred embodiment of the invention, the foam is a polyurethane foam with a density of at least 0.5kg/l and a mechanical loss factor of more than 0.40. The damping material properties of certain highly damped polyurethane foams are used to damp the vibrating structure. Upon vibration damping, the kinetic energy (kinetic energy) is converted into another energy form no longer relevant to the vibration behavior, and the resonance phenomenon of the member or structure can be kept within a narrower limit.

In the context of the invention, the additive preferably comprises silicate and/or barite, in particular with a density of between 2.5kg/l and 8.0kg/l, in particular 4.0kg/l to 7.8kg/l, in particular 4.5 kg/l. These materials have a high density and therefore bring about a very effective damping of the disturbing frequencies of the natural vibrations of the rail part according to the invention by introducing additional mass and by increasing the stiffness.

Alternatively or additionally, the additive may comprise a cavity filling stone, in particular a cavity filling stone made of concrete, and/or a metal body, as this corresponds to a preferred embodiment of the invention.

The shear stiffness and thus the damping effect of the composite material can be influenced in a targeted manner by a suitable choice of the particle size of the additives. Preferably, therefore, according to a preferred embodiment of the invention, the block of additive has an equivalent diameter of at least 2 mm. This minimum particle size is also subject to the stress of ensuring a rapid and reliable enveloping of the additive in the foam material, which is of course advantageous for a reliable fixing of the additive in the rail part according to the invention and is subject to the stress of the entire vibration system, which connects the additive to the rail part according to the invention in a damping manner.

The invention is preferably further developed in that the composite material only partially fills the at least one hollow space, so that a space free of the composite material remains between a surface of the composite material facing the underside of the rail part and a plane of a bottom face configuring the underside of the rail part. Thereby, decoupling of the damping composite from the substructure of the rail is achieved.

Preferably, at least one covering element is fixed in the hollow space, which covering element delimits a volume which can be occupied by the composite material towards the underside of the rail part. In the broadest sense, this serves to additionally mechanically retain the composite material, which is itself adhered to the walls of the hollow space by the PUR foam material, in the hollow space in order to counteract any loosening of the composite material that may occur over a longer lying time of the rail part according to the invention. In this case, the cover element is preferably arranged at a distance from the plane of the bottom side of the rail part if, as described above, a decoupling from the substructure of the rail is to be achieved.

In this respect, the invention is preferably further developed in that the covering element is rigidly connected, in particular materially connected, to the wall of the hollow space. The connection of the covering element to the rail part is therefore as strong as possible in order to ensure as constant a support of the composite material in the hollow space as possible. A material connection is understood to be a connection which is produced, for example, by welding.

According to a preferred embodiment of the invention, the covering element is screwed to a threaded rod which is rigidly connected, in particular materially connected, to the bottom wall of the hollow space. In this preferred type of fixing of the covering element, the composite material is passed through by the threaded rod and a particularly good force transmission onto the covering element and thus onto the composite material in the hollow space is achieved, in order to prevent the composite material from escaping from the walls of the hollow space and to ensure the activation of the composite material.

Alternatively or additionally, the invention is characterized in that the covering element is connected, preferably materially or in the case of a fixing element, to a side wall of the at least one hollow space. The cover element can be welded to the side wall of the hollow space or can be fixed by means of a fixing element, such as a clip or fixing angle or the like, which is welded or screwed into the side wall.

According to a preferred embodiment of the invention, a further improved fastening of the joint of the composite material to the wall of the hollow space is achieved in that the covering element can be tensioned with the rail part after the hardening of the foam material. This can be achieved to a certain extent in the above-described embodiments in which the covering element is screwed to a threaded rod which is rigidly connected, in particular materially connected, to the bottom wall of the hollow space. After the foam material has set, the cover element can be placed guided by the threaded rod onto the surface of the foam material and then screwed in with the nut. Depending on how firmly the nut is tightened, a tensioning of the covering element and therefore of the composite material in the hollow space is achieved, whereby the density and therefore the damping properties of the composite material can also be influenced additionally.

Preferably, the covering element is configured as a covering grid. The covering grid has certain advantages in fastening the composite material in the hollow space in the transverse direction and furthermore allows the area between the composite material and the covering grid to dry after deposition, which may be beneficial for the service life of the composite material over a long lay-up time.

The most significant noise emissions in guideway traffic associated with the present invention occur when the guideway vehicle is driven over a switch turnout. The guide rail turnout consists of a straight main rail and a curved branch rail. The turnout frog is a core element in the turnout. The guide rails lying inside intersect here. These rails are interrupted at what is known as the fork gap, so that the wheel rims of the wheels running on the opposite wing rails can run through them without interference. The frog comprises a frog tip, a frog gap, a wing rail and a connecting rail. When driving through the fork gap, the interrupted driving surface can cause dynamic impacts at the fork point. Such shock loads result in broadband vibratory excitation of the frog and surrounding rail. These vibrations are emitted to the surroundings in the form of audible airborne sounds and perceptible body sounds and produce disturbing effects. At the same time, the switch fork has a hollow space at its underside, which is caused by the construction, which hollow space acts as a resonator and further enhances the noise emission. The invention therefore has particular utility if, as in a preferred embodiment of the invention, the rail element is a switch point and the at least one hollow space extends in the longitudinal direction at least in the region of the point tip of the switch point. Thus, with the rail part according to the invention, a significant reduction of the noise emission at the turnout can be achieved.

The method according to the invention for manufacturing a rail part comprises at least the following steps:

providing a rail part, in particular a switch point, in particular a manganese cast point, with at least one hollow space,

-filling the hollow space at least partially with a pourable, bulk additive or additives,

-casting the remaining volume in the hollow space with a foamable mass surrounding the bulk additive, so as to obtain a composite material comprising an elastomeric foam material and a plurality of bulk additives distributed in the elastomeric foam material.

The damping effect is based on the total mass of the elastomer foam material with the pourable additive or additives and the damping characteristics of the elastomer in the hollow space. The additive is lumpy and can therefore be bypassed by the mass of the highly damped foam material before foaming, in order to produce a composite material in the hollow space. The mass of the foam material here also fills the hollow spaces between the individual additives, whereby a continuous body of composite material is obtained. Due to the elastic properties of the foam material, the additive is vibrationally connected to the rail part, and due to its inhomogeneity, when passing through the rail part according to the invention, results in a broad-band vibration damping and thus in a simple and particularly cost-effective manner in a significant reduction of noise emissions.

The method according to the invention is preferably further developed in that the surface of the hollow space is pretreated before the filling of the hollow space by a method, for example by descaling, etching, sandblasting and/or the application of adhesion promoters, for priming. This may be necessary or useful in order to improve the adhesion of the composite material at the walls of the hollow space in order to achieve as long a lying time as possible of the rail part manufactured with the method according to the invention.

Preferably, the casting is carried out with a mass (or blank, master) that foams into polyurethane foams, in particular polyurethane foams having a density of at least 0.5kg/l and a mechanical loss factor of more than 0.40. The damping material properties of the particular polyurethane foam material are used to damp the vibrating structure.

In the context of the present invention, silicates and/or barites, in particular silicates and/or barites with a density of between 2.5kg/l and 8.0kg/l, in particular from 4.0kg/l to 7.8kg/l, in particular 4.5kg/l, are preferably used as the additive. These materials have a high density and therefore bring about a very effective damping of the disturbing frequencies of the natural vibrations of the rail part according to the invention by introducing additional mass and by increasing the stiffness.

Alternatively or additionally, as this corresponds to a preferred embodiment of the invention, a cavity filling stone, in particular a cavity filling stone made of concrete, and/or a metal body is used as the additive.

Preferably, an additive having an equivalent diameter of at least 2mm of the mass of additive is used. This minimum particle size is also subject to stress in order to ensure a rapid and reliable enveloping of the additive in the foam material, which is of course preferred for a reliable fixing of the additive in the rail part according to the invention and is subject to stress in the entire vibration system, which links the additive to the rail part according to the invention in a damping manner.

Preferably, at least one covering element is fixed in the hollow space, which covering element delimits a volume which can be occupied by the composite material towards the underside of the rail part. In the broadest sense, this serves to additionally mechanically retain the composite material, which is itself adhered to the walls of the hollow space by the PUR foam material, in the hollow space in order to counteract any loosening of the composite material that may occur over a longer lying time of the rail part according to the invention.

According to a preferred embodiment of the invention, the filling or pouring is performed through an area of the opening of the hollow space not covered by the at least one covering element. This means that the cover element is first fixed at the rail part and the filling takes place through the free space (or empty space, i.e. Freiraum) or gap between the opening of the hollow space and the cover element. This mode of operation is of course only possible with the composite material according to the invention, which, because of its pourable and block-like additive, has to be filled in simply and without having to be arranged in a complicated manner in the hollow space and fixed in a locally defined manner.

According to a preferred embodiment of the invention, a further improved fastening of the joint of the composite material to the wall of the hollow space is achieved in that the covering element can be tensioned with the rail part after the hardening of the foam material. This can be achieved to a certain extent in the embodiments described above in connection with the rail part according to the invention, in which the covering element is screwed to a threaded rod which is rigidly connected, in particular materially connected, to the bottom wall of the hollow space. Depending on how firmly the nut is tightened, a tensioning of the covering element and therefore of the composite material in the hollow space is achieved, whereby the density and therefore the damping properties of the composite material can also be influenced additionally.

Drawings

The invention is explained in more detail below with the aid of embodiments shown in the drawings. In the drawings:

figure 1 shows the underside of the switch point opposite the rolling surface,

figures 2base:Sub>A-2D showbase:Sub>A plurality of cross-sectional views of the switch frog along the linesbase:Sub>A-base:Sub>A, B-B, D-D and E-E according to figure 1,

figure 3 shows a view of a representative segment of a switch frog according to figure 1,

fig. 4 shows a plan view of the region of the hollow space in the switch point which is covered by the cover element, an

Fig. 5 shows a graphical representation of the sound level reduction of the immediate surroundings of a switch fork according to the invention.

Detailed Description

In fig. 1, the switch fork is denoted by reference numeral 1 and it can be seen that a plurality of hollow spaces 3 are arranged on the underside 2 of the switch fork 1, wherein, depending on which section of the switch fork 1 is viewed, a different number of hollow spaces are arranged next to one another transversely to the direction of travel (indicated by the double arrow 4). This is caused by the fact that the rails of the rails crossing each other at the switch come together and are guided apart from each other again, and the hollow space at the lower side is caused by the rail profile at the rolling surface. For better clarity, only a part of the hollow space 3 is provided with reference numerals in fig. 1. This is also retained in fig. 2, where like parts are provided with like reference numerals.

In the sectional view according to fig. 2, the rolling surface 5 or the rolling surfaces 5 can also be seen in each case. The hollow space 3 at the underside 2 takes up a considerable volume and it is understood that when a train is driven at high speed over the switch fork 1, strong vibrations and resonances occur, which are correspondingly associated with high noise emissions. The reference numeral 6 denotesbase:Sub>A fork point, on which the train wheel is guided after passing throughbase:Sub>A fork gap 7, which is located in the region of the cross sectionbase:Sub>A-base:Sub>A in fig. 1 and 2. In fig. 2, the hollow space 3 is completely filled with a damping means 8 made of the above-described composite material consisting of PUR foam and additives, whereby an excellent damping of noise emissions is achieved.

In fig. 3, it can be seen that the hollow space 3 can be covered with a covering element 9, wherein the covering element 9 can be connected rigidly to the wall 10 of the hollow space 3 using a fastening element 11 or materially by welding. Alternatively or additionally, the covering element 9 can be screwed with the threaded rod 12 using the nut 13, wherein the threaded rod 12 is rigidly connected with the bottom wall 10 'of the hollow space, for example in the sense of a screw connection in the bottom wall 10' or a material connection, for example by welding.

In fig. 4, a covering element 9 in the form of a covering grid 9' is shown and it can be seen that the covering grid is connected with the wall 10 of the hollow space 3 via a plurality of fixing elements 11. It can also be seen that the filling or pouring with PUR foam material takes place through the region 14' of the opening 14 of the hollow space 3 which is not covered by the at least one covering element 9.

The measurement results of the laboratory tests can be seen in fig. 5, in which the measured frequencies of the sound measurement are plotted on the abscissa and the measured sound pressure in decibels, relative to one another, in relation to the excitation force when the rail part according to the invention is excited. In the case of the rail part according to the invention, the sound pressure is reduced by 17.7dB with respect to the excitation force in the range between 100Hz (hertz) and 10000Hz, and in particular in the range between 1000Hz and 10000 Hz. This is a significant drop and then the burden on the track line population due to noise can be significantly reduced. It is particularly advantageous to also virtually completely eliminate frequencies in the case of 30Hz to 40Hz, which are perceived as particularly disturbing, in particular in slow-moving rail vehicles, for example in urban areas.

Claims

1. A rail part (1), in particular a turnout frog (1), comprising a running surface for a wheel of a rail vehicle, an underside (2) opposite the running surface, and at least one hollow space (3) open towards the underside (2), wherein a damping means (8) is accommodated in the hollow space (3), characterized in that the damping means (8) is formed by a composite material arranged in the hollow space (3), the composite material comprising an elastomeric foam material and a plurality of block-shaped additives distributed in the elastomeric foam material.

2. The track component of claim 1, wherein the foam material is configured as a hybrid-cell foam material.

3. The rail member according to claim 1 or 2, characterized in that the foam material is a polyurethane foam material with a density of at least 0.5kg/l and a mechanical loss factor of more than 0.40.

4. The rail component of claim 1, 2 or 3, characterized in that the additive comprises silicate and/or barite, in particular silicate and/or barite with a density of between 2.5kg/l and 8.0kg/l, in particular 4.0kg/l to 7.8kg/l, in particular 4.5 kg/l.

5. The rail part according to any one of claims 1 to 4, characterized in that the additive comprises a cavity filling stone, in particular a cavity filling stone composed of concrete, and/or a metal body.

6. The rail member according to any one of claims 1 to 5, wherein the block of additive has an equivalent diameter of at least 2 mm.

7. Rail component according to any one of claims 1 to 6, characterized in that the composite material only partially fills the at least one hollow space (3), so that a space free of the composite material remains between the surface of the composite material facing the underside of the rail component (1) and the plane structuring the bottom face of the underside (2) of the rail component (1).

8. The rail part according to one of claims 1 to 7, characterized in that at least one covering element (9, 9') is fixed in the hollow space (3), which covering element delimits a volume which can be occupied by the composite material towards the underside (2) of the rail part (1).

9. The rail part according to claim 8, characterized in that the covering element (9, 9') is preferably arranged spaced apart from the plane of the bottom face of the rail part (1).

10. The rail part according to claim 8 or 9, characterized in that the covering element (9, 9') is rigidly connected, in particular materially connected, to the wall (10) of the hollow space (3).

11. The rail part according to claim 8, 9 or 10, characterized in that the covering element (9, 9 ') is screwed with a threaded rod (12) which is rigidly connected, in particular materially connected, with the bottom wall (10') of the hollow space (3).

12. The rail part according to any one of claims 8 to 11, characterized in that the covering element (9, 9') is connected, preferably materially or in the case of a fixing element (11), with a side wall of the at least one hollow space (3).

13. Rail part according to any of claims 8 to 12, characterized in that the covering element (9, 9') can be tensioned with the rail part (1) after hardening of the foam material.

14. The rail part according to any one of claims 8 to 13, characterized in that the covering element (9, 9') is configured as a covering grid.

15. The rail element according to one of claims 1 to 14, characterized in that the rail element (1) is a switch point (1) and the at least one hollow space (3) extends in the longitudinal direction at least over the area of the point tip of the switch point (1).

16. A method for manufacturing a rail part, the method comprising at least the steps of:

-providing a rail part (1), in particular a switch point (1), in particular a manganese cast point, with at least one hollow space (3),

-filling the hollow space (3) at least partially with a pourable, block-shaped additive or additives,

-casting the remaining volume in the hollow space with a foamable mass surrounding the bulk additive, so as to obtain a composite material comprising an elastomeric foam material and a plurality of blocks of additive distributed in the elastomeric foam material.

17. Method according to claim 16, characterized in that the surface of the hollow space (3) is pretreated with a method before the filling of the hollow space (3), for example by descaling, etching, sandblasting and/or the application of an adhesion promoter, for priming.

18. Method according to claim 16 or 17, characterized in that the casting is carried out with a mass which is foamed into a polyurethane foam, in particular a polyurethane foam having a density of at least 0.5kg/l and a mechanical loss factor of more than 0.40.

19. Method according to claim 16, 17 or 18, characterized in that silicate and/or barite, in particular silicate and/or barite having a density of between 2.5 and 8.0kg/l, in particular 4.0 to 7.8kg/l, in particular 4.5kg/l, is used as the additive.

20. Method according to any one of claims 16 to 19, characterized in that a cavity filling stone, in particular a cavity filling stone consisting of concrete, and/or a metal body is used as the additive.

21. The method according to any one of claims 16 to 20, wherein an additive having an equivalent diameter of at least 2mm of the mass of additive is used.

22. The method according to any one of claims 16 to 21, characterized in that at least one covering element (9, 9') is fixed in the hollow space (3), which covering element delimits a volume which can be occupied by the composite material towards the underside (2) of the rail part (1).

23. Method according to claim 22, characterized in that the filling or pouring is performed through the area of the opening of the hollow space (3) not covered by the at least one covering element.

24. Method according to claim 22 or 23, characterized in that the at least one covering element (9, 9') is tensioned with the rail part (1) after hardening of the foam material.