Abstract
A method is provided for foaming a ballast bed of a railway track wherein the railway track comprises sleepers positioned on the ballast bed and rails positioned on the sleepers, wherein the rails are covered at least in a partial area along a region of the ballast bed to be foamed, and a foaming agent is introduced into the ballast bed while the rails are covered, wherein the ballast bed has in a sleeper bay defined by two successive sleepers an upper side facing against the gravitational direction, and the ballast bed is heaped up so that the upper side of the ballast bed reaches at least up to an underneath side of the sleeper facing in the gravitational direction.
Claims
1. A method for foaming a ballast bed of a railway track, wherein the railway track comprises sleepers placed on the ballast bed, and rails, placed on the sleepers, wherein the rails are covered with at least one cover at least along one region of the ballast bed which is to be foamed, and a foaming agent is introduced into the ballast bed whilst the rails are covered, wherein the ballast bed has in a sleeper bay defined by two successive sleepers an upper side facing against the gravitational direction, and the ballast bed is heaped up so that the upper side of the ballast bed is positioned at a level above an underside of the sleeper facing in the gravitational direction, wherein the foaming agent is applied from an outlet at a level above a running surface of the rail wherein the level is maintained substantially constant for foaming two successive sleeper bays.
2. The method according to claim 1 in which the level of the upper side of the ballast bed in the sleeper bay corresponds substantially to the nominal operating level of the ballast bed in the sleeper bay during regular rail traffic operation.
3. The method according to claim 1 wherein at least the rail and/or the sleeper is covered with at least one cover aligned inclined relative to the gravitational direction.
4. The method according to claim 3 wherein the cover and/or the covering hood has at least one guide for continuously entraining the covering hood and/or the cover on the rail.
5. The method according to claim 3 wherein the cover plate and/or the covering hood has a repellent means for repelling foaming agent.
6. The method according to claim 5 wherein the repellent means is more particularly designed as a coating.
7. The method according to claim 1 wherein at least the rail and/or the sleeper is covered by a covering hood wherein the covering hood comprises a first cover and a second cover connected at an angle to the first cover.
8. The method according to claim 1 wherein the foaming agent is introduced so far into the ballast bed that after the foaming of the foaming agent the resulting foam remains in the sleeper bay substantially completely below the upper side of the ballast bed.
9. The method according to claim 1 wherein the dispensing of the foaming agent can be interrupted when passing over a rail and/or from one sleeper bay to a following sleeper bay.
10. The method according to claim 1 wherein the foaming agent is applied by a railway vehicle travelling on the rails of the railway track, wherein the railway vehicle for foaming the ballast bed of the railway track moves forwards substantially continuously, more particularly at a constant travelling speed.
Description
(1) The invention will now be explained by way of example with reference to the accompanying drawings using a preferred embodiment, wherein the features explained below can represent one aspect of the invention each individually and also in combination. The drawings show:
(2) FIG. 1: a diagrammatic plan view of a railway track;
(3) FIG. 2: a diagrammatic sectional view of a detail of the railway track during foaming;
(4) FIG. 3: a diagrammatic plan view of the railway track of FIG. 2;
(5) FIG. 4: a perspective view of a continuously entrainable cover;
(6) FIG. 5a: a diagrammatic plan view of a cover;
(7) FIG. 5b: a diagrammatic plan view of a railway track with a cover;
(8) FIG. 6: a side view of a railway track with two covers.
(9) The railway track 10 illustrated in FIG. 1 has a ballast bed 12 on which several sleepers 14 are placed. The sleepers 14 support two rails 16 which are aligned in the travel direction, in the longitudinal direction X, and which are arranged spaced relative to one another corresponding to the intended track width. A sleeper bay 18 is formed between two sleepers 14 and the two rails 16.
(10) As shown in FIG. 2, the rail 16 can be covered with a covering hood 20 during foaming of the ballast bed 12. The covering hood 20 has in the illustrated embodiment a first cover 22 and a second cover 24 which are connected to one another in the manner of a pitched roof. The covering hood 20 has at least one intermediate member 38 which is arranged on the covers 22, 24 in the transverse direction Y, substantially at right angles to the rail 16. The intermediate member 38 can be designed in the form of a one-sided cover with an incline towards the sleeper bay. The intermediate member 38 can be designed in the form of a roof with two inclines. In the illustrated embodiment the covering hood 20 is spaced from an upper side 26 of the ballast bed 12 in the region of the sleeper bay 18. The covering hood 20 can be centred by the cover 22, 24, which laterally adjoins a rail head 28 of the rail 16, and can be clamped with the rail 16 by its inherent weight. A running surface 30 of the rail 16 formed by the rail head 28 and facing against the gravitational direction is thereby covered substantially entirely. The sleeper 14 is covered by the intermediate member 38. When a foaming agent is applied from a mixer head 32 which is provided in a transverse direction Y via an outlet 34 at a level which in the gravitational direction is above the running surface 30 of the rail 16 and where applicable above the covering hood 20, the substantially fluid foaming agent can flow away from the running surface 30 of the rail 16 and the sleeper 14 at the covers 22, 24 of the covering hood 20 and the intermediate member 38 and instead pass to the ballast bed 12. It is hereby not necessary for the sleeper bay 18 to be dug out so that the upper side 26 of the ballast bed 12 can already correspond in the region of the sleeper bay 18 to the nominal operating height of the ballast bed 12 during the regular rail operation. The upper side 26 of the ballast bed 12 in the region of the sleeper bay 18 can thereby be located at a level which is provided in the gravitational direction above an underneath side 36 of the sleeper 14 facing the base grade.
(11) As shown in FIG. 3, the covering hood 20 has at least one intermediate member 38 arranged transversely to the travel direction. The intermediate members 38 can be arranged on the covers 22, 24 in the travel direction or opposite the travel direction and can protect at least in part the sleeper (not shown) and at least in part a fastening member 40, by way of example in the form of a Vossloh clamp, against soiling by the foaming agent. In the event of movement of the mixer head 34 in the transverse direction Y the rail 16 can be protected against soiling by the covers 22, 24.
(12) The covering hood 20 in FIG. 4 has covers 22, 24 and two intermediate members 38 wherein the intermediate members 38 have at least the width of the sleepers. The covering hood 20 has a rail-related guide 42 for continuously entraining the covering hood 20 in the form of rollers which roll along the rails 16 in the longitudinal direction X. The rollers 42 are connected via a rod linkage 44 on which the covering hood 20 is positioned. The mixer head 32 can be moved both in the transverse direction and also in the longitudinal direction X relative to the railway vehicle (not shown) and/or the covering hood 20. With a continuous movement of the railway vehicle and/or the covering hood 20 the mixer head 32 can thereby be moved substantially parallel to the sleepers 14 in order to apply the foaming agent into the sleeper bay 18. The mixer head 32 can execute a pendulum movement in the transverse direction Y about a rail 16 wherein the pendulum movement can move round the sleeper 14 at the end.
(13) FIG. 5a shows a covering hood 20 arranged on two rails 16 and having the first and second covers 22, 24 and two intermediate members 38. The covering hood 20 is shown in FIG. 5b on a railway track 10, wherein two mixer heads 32 are provided, one for each rail 16. The mixer heads 32 can be moved independently of one another both in the longitudinal direction X and also in the transverse direction Y. With a continuous movement of the covering hood 20 in the longitudinal direction X the mixer heads 32 can each swing in a pendulum movement about a rail 16 and thereby follow a U-shaped travel path 46 with components in the longitudinal direction X and transverse direction Y, wherein the travel path 46 can be guided each time around the outside end of the sleepers 14. The foaming agent can be introduced into the ballast bed 12 mainly in the region of the rails 16.
(14) An arrangement of two covering hoods 20 which can each have one or two mixer heads 32 is shown in FIG. 6. The foaming agent 48 can be applied onto the ballast bed 12, more particularly in the sleeper bays 18, through the outlets 34 of the mixer heads 32. The covering hoods 20 are continuously movable along the rails 16 in the longitudinal direction X by guides 42. The foaming agent 48 can thereby be dispensed continuously wherein the rails 16 and the sleepers 14 are protected by the covering hoods 20 from becoming soiled.
