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EP-4735690-A1 - METHOD AND TRACK-LAYING MACHINE FOR TAMPING SLEEPERS OF A TRACK

EP4735690A1EP 4735690 A1EP4735690 A1EP 4735690A1EP-4735690-A1

Abstract

Proposed is a method for tamping sleepers (9) of a track (3) by means of a tamping assembly (6), the tamping tools (12) of which are plunged into a ballast bed (11) and squeezed toward one another, with the condition of the ballast bed (11) being determined. Here, a setting value (E) for a squeeze pressure (pB) for pressurizing squeeze cylinders (16) of the tamping assembly (6) is automatically specified on the basis of the determined condition of the ballast bed (11). It is thus possible for the squeeze pressure (pB) to be adapted during every tamping operation to the conditions in the ballast bed (11). The invention also relates to a system for tamping sleepers of a track.

Inventors

  • KOCZWARA, Christian
  • DAXBERGER, HARALD

Assignees

  • Plasser & Theurer Export Von Bahnbaumaschinen Gesellschaft m.b.H.

Dates

Publication Date
20260506
Application Date
20240625

Claims (10)

  1. 1. Method for tamping sleepers (9) of a track (3) by means of a tamping unit (6), the tamping tools (12) of which are immersed in a ballast bed (11) and placed next to one another, the nature of the ballast bed (11) being determined, characterized in that on the basis of the determined nature of the ballast bed (11) a setting variable (E) for a tamping pressure (p B ) for applying tamping cylinders (16) of the tamping unit (6) is automatically specified.
  2. 2. Method according to claim 1, characterized in that the setting variable (E) is specified as a proportion of an available system pressure of a hydraulic system coupled to the tamping unit (6).
  3. 3. Method according to claim 1 or 2, characterized in that the setting variable (E) is displayed in an output device (43).
  4. 4. Method according to one of claims 1 to 3, characterized in that during a lifting and tamping process of the track (3) the setting variable (E) is automatically adjusted as a function of a lifting value (H) and/or a setting time (t B ) and/or a number (A) of tamping cycles.
  5. 5. Method according to one of claims 1 to 4, characterized in that the setting variable (E) is fed to a control device (35) of the tamping unit (6) and that the auxiliary cylinders (16) are controlled by means of the control device (6) in accordance with the setting variable (E).
  6. 6. Method according to one of claims 1 to 5, characterized in that the supply pressure (p B ) is automatically adjusted during a supply process depending on a detected movement variable of the stuffing tool (6) and/or a reaction force (F R ) acting on the stuffing tool (12).
  7. 7. Method according to one of claims 1 to 6, characterized in that for determining the condition of the ballast bed (11) during an immersion process of the tamping tools (12) into the ballast bed (11) a measured variable correlating with a penetration force (F E ) is recorded and that the setting variable (E) for the setting pressure (p B ) is derived from the measured variable.
  8. 8. Method according to claim 7, characterized in that the condition of the ballast bed (11) is determined on the basis of several measured values of the measured variable at different measuring times during the immersion process and the setting variable (E) is derived therefrom.
  9. 9. Method according to claim 7 or 8, characterized in that measured values of the measured variable are recorded during several tamping operations and the condition of the ballast bed (11) is determined therefrom.
  10. 10. System (1) for tamping sleepers (9) of a track (3) by means of a tamping unit (6) with tamping tools (12) which can be immersed in a ballast bed (11) and positioned relative to one another, the system (1) being designed to determine the condition of the ballast bed (11), characterized in that a characteristic value for the condition of the ballast bed (11) of a Evaluation device (28) for deriving a setting variable (E) for an auxiliary pressure (p B ) for actuating auxiliary cylinders (16) of the tamping unit (6).

Description

Method and track construction machine for tamping sleepers of a track The invention relates to a method for tamping sleepers of a track using a tamping unit, the tamping tools of which are immersed in a ballast bed and placed next to each other, whereby the nature of the ballast bed is determined. The invention also relates to a corresponding system for carrying out the method. A generic method is known from AT 520698 A1. A sensor is used to record the load on the tamping unit in addition to determining the condition of a ballast bed. Specifically, a penetration force is determined during the penetration process of a tamping tool into a ballast bed. A load-time curve derived from this forms the basis for evaluating the ballast condition. In AT 521850 A1, a tamping tool is also used to immerse it in order to draw conclusions about the condition of a ballast bed. This involves a controlled lowering movement of the tamping tools, with at least one variable processed in the control loop being fed to an evaluation device to derive a characteristic variable for the ballast bed. AT 520056 A1 discloses another method for determining the condition of a ballast bed. This involves recording the force transmitted to the track ballast due to a horizontal vibration movement of tamping tools in order to draw conclusions about the condition of the ballast bed. AT 521798 A1 discloses a method for determining the condition of a ballast bed using a working unit for ballast compaction, wherein the working unit comprises an electric drive. A ballast bed characteristic is derived from at least one operating variable of the electric drive using an evaluation device. The invention is based on the object of enabling improved operation of the tamping unit on the basis of the method of the type mentioned at the outset. It is also an object of the invention to provide a correspondingly improved system for tamping sleepers on a track. According to the invention, these objects are achieved by the features of independent claims 1 and 10. Dependent claims specify advantageous embodiments of the invention. [Claim 1] Based on the determined properties of the ballast bed, a setting value for a supply pressure for applying the supply cylinders of the tamping unit is automatically specified. The supply pressure is an important value in asynchronous constant pressure tamping, in which tamping tools located opposite one another are tamped with the same pressure in relation to a sleeper to be tamped. The same pressure is achieved by jointly activating the supply cylinders assigned to the tamping tools. During a specified tamping time, different reaction forces of the ballast on the respective tamping tool may lead to different tamping paths. The specified setting time and the set setting pressure are important variables for influencing the compaction quality of the ballast. Both variables are selected depending on the local conditions at the point on the track to be tamped. The current condition of the ballast bed is of key importance here. The information on the condition of the ballast bed can in particular contain information on a grain size, a fine fraction, a degree of compaction, a degree of contamination, in particular a degree of vegetation, and/or a ballast bed stiffness. The condition can also include information on a layer thickness of the track ballast, in particular on a filling height relative to the underside of a track sleeper. In particular, the nature of the ballast bed is understood to mean at least one property that is crucial for the operation of the track. The properties that are particularly important are those that affect the load-bearing capacity, the rigidity and/or the damping properties of the ballast bed. The spectrum here extends from a relatively loose ballast bed at the start of track construction (new track, soft ballast bed) to a heavily contaminated and compact ballast bed towards the end of a maintenance period (hard ballast bed). In the latter case, a significantly higher setting pressure is required in order to move ballast grains into a new, compacted structure during a setting process. Until now, it was the operator's responsibility to set a suitable auxiliary pressure based on predictable influencing factors. The method according to the invention automatically sets the auxiliary pressure depending on the The properties of the ballast bed are determined prior to the tamping tool being used. This makes it possible to adapt the tamping pressure to the conditions of the ballast bed during each tamping process. Typically, the adjustment is in a range of 8 MPa to 12 MPa (80-120 bar), which generally results in a tamping force of 3 kN to 12 kN at the free end of the respective tamping tool (pick plate). The automatic setting of the supply pressure depending on the ballast bed condition ensures a consistent tamping quality. The risk of sleeper displacement is eliminated. In addition, the demands placed on an op