EP1432835B1 - Method for thermal treatment of rails - Google Patents

Method for thermal treatment of rails Download PDF

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Publication number
EP1432835B1
EP1432835B1 EP02777151A EP02777151A EP1432835B1 EP 1432835 B1 EP1432835 B1 EP 1432835B1 EP 02777151 A EP02777151 A EP 02777151A EP 02777151 A EP02777151 A EP 02777151A EP 1432835 B1 EP1432835 B1 EP 1432835B1
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EP
European Patent Office
Prior art keywords
cooling
rail
temperature
rail head
rails
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Expired - Lifetime
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EP02777151A
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German (de)
French (fr)
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EP1432835A2 (en
Inventor
Klaus Küppers
Meinert Meyer
Thomas Nerzak
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SMS Group GmbH
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SMS Meer GmbH
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/04—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rails
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/84—Controlled slow cooling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D11/00—Process control or regulation for heat treatments
    • C21D11/005—Process control or regulation for heat treatments for cooling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/009—Pearlite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment

Definitions

  • the invention relates to a method for the thermal treatment of rails, in particular of hot-rolled rail or railway rails with profile parts different mass, the rails from the rolling heat through a targeted thermal treatment and cooling in the profile parts in the profile area, in particular obtained in the rail head, a desired texture with increased strength.
  • the rail head first in the passage in sufficient depth up to 50 mm by means of burner or induction heating to an austenitizing temperature of 950 to 1050 ° C, then with compressed air, the rail head in a first cooling stage within from 10 to 20 seconds to 650 to 600 ° C before the area of pearlite conversion to cool and in a second cooling stage with respect to the first stage throttled Air volume within 2 to 4 minutes to about 400 ° C until the end the Perlitumwandlung to form a fine-lamellar pearlitic structure cool. Subsequently, the rail head is again set to 600 to 650 ° C for heated for a period of 4 to 6 minutes and then quickly to below 100 ° C. deterred.
  • a method Specify through which a targeted thermal treatment specifically during the cooling of the rail head allows and with simple means Microstructure is produced, which has a fine-lamellar perlite, which is characterized by a certain hardness level and associated with a high resistance to abrasion characterized and wherein during the cooling process in particular in the Edge zones of the rail head no bainite arises.
  • the cooling section would have to be operated with a significantly lower heat flux density, or the heat transfer coefficient to be set would be about 30 to 40% lower in order to avoid bainite formation in the edge zones of the rail head.
  • the heat transfer coefficient to be set would be about 30 to 40% lower in order to avoid bainite formation in the edge zones of the rail head.
  • the targeted pre-cooling to a core temperature of the rail head from 750 to 850 ° C can according to the invention by cooling in air with natural convection or forced with the help of fans. But it is also possible with To cool the help of nozzles with a water-air mixture (aerosol cooling), this cooling preferably on a cross tractor with appropriate Number of moorings is made.
  • the surface temperature becomes the rail head center measured without contact using a pyrometer.
  • the boundary zone temperature determined here then depends on the type of cooling and intensity about 30 to 60 ° C below the still existing Kemtemperatur.
  • the temperature of Rail head during the entire thermal treatment starting from entering the Vorkssel issued until leaving the Fertigkühl issued measured.
  • the measured values are transferred to a measuring and control device fed and serve to control the individual process steps to be performed, including heating upstream of the final cooling.
  • FIG. 1 shows the cross section of a rail 1.
  • the rail 1 is made from profile parts of different mass, the rail head 2 with edge zone 5 and Core zone 6, the middle part 3 and the rail foot 4.
  • the edge zone 5 of the rail head Fig. 2 is shown in phantom in Fig. 1; it is the area that is primarily through targeted thermal treatment converted into a fine-lamellar pearlite structure is to be, without that in the thermal treatment in this edge zone or 5 bainite is created in this area.
  • FIG 2 is a schematic system 10 for carrying out the thermal Treatment according to the invention shown.
  • the plant 10 is - in the rolling line x-x behind the last rolling mill 11 arranged one behind the other - from a Pre-cooling device 12, a preferably inductive heating device 13 and a Fertigkühl Surprise 14, of the rail 1 after its exit from the Roll stand 11 are passed through one after the other.
  • the control of the thermal Treatment - includes the intensity of cooling or heating as well the flow rate through the individual system parts 12, 13, 14, happens depending on the respective measured temperature by a measuring and control device 15, which via corresponding lines 16, 17, 18 for the Temperature measured values and the control signals with the respective installation parts 12, 13, 14 are connected.
  • thermo treatment plant can Of course, depending on the type and size of the rails and the type of the selected Pre - and final cooling as well as the scope of the measuring and control device be varied as far as compliance with the arranged one behind the other process steps of the invention is fully preserved content.

Abstract

In order to obtain a fine-lamellar perlite structure in the edge region of the heads of rails ( 1 ), especially hot-rolled rails for carriageways or railways, by specific thermal treatment during cooling from the rolling heat without the formation of bainite, precooling ( 12 ) occurs in order to achieve a core temperature of approximately 750-850° C., and the temperature of the more intensively cooled edge region is raised by intermediate heating ( 13 ) to at least said core temperature and finally cooled ( 14 ).

Description

Die Erfindung betrifft ein Verfahren zur thermischen Behandlung von Schienen, insbesondere von warmgewalzten Fahr- bzw. Eisenbahnschienen mit Profilteilen unterschiedlicher Masse, wobei die Schienen aus der Walzhitze durch eine gezielte thermische Behandlung und Kühlung im der Profilteile im Profilbereich, insbesondere im Schienenkopf, ein gewünschtes Gefüge mit erhöhter Festigkeit erhalten.The invention relates to a method for the thermal treatment of rails, in particular of hot-rolled rail or railway rails with profile parts different mass, the rails from the rolling heat through a targeted thermal treatment and cooling in the profile parts in the profile area, in particular obtained in the rail head, a desired texture with increased strength.

Es ist bekannt, Schienen aus der Walzhitze bis auf Temperaturen unterhalb 80° auf Kühlbetten abzukühlen. Wegen der asymmetrischen Anordnung der Massen aufgrund der unterschiedlichen Profilteile der Schienen ergibt sich zwischen Kopf und Fuß der Schienen ein unterschiedliches Abkühlverhalten. Der Fuß kühlt sich schneller ab als der Kopf, woraus resultiert, dass sich die Schiene beim Erkalten krümmt. Durch Vorbiegen der noch heißen Schiene oder durch einen unterschiedlichen Abkühlprozess für Kopf und Fuß kann dieser Krümmung vorgebeugt werden. Durch das Vorbiegen oder durch den differenzierten Kühlprozess werden jedoch Eigenspannungen in der Schiene erzeugt, die deren mechanische Eigenschaften und damit die Lebensdauer nachteilig beeinflussen.It is known, rails from the rolling heat to temperatures below 80 ° to cool on cooling beds. Because of the asymmetric arrangement of the masses due to the different profile parts of the rails results between head and foot of the rails a different cooling behavior. The foot cools faster than the head, which results in the rail cooling down curves. By pre-bending the still hot rail or by a different one Cooling process for head and foot can be prevented this curvature. By pre-bending or by the differentiated cooling process However, residual stresses generated in the rail, their mechanical properties and thus adversely affect the life.

Durch das US-A-4.933 024 ist es bekanntgeworden, eine Schiene aus der Walzhitze heraus auf Ar3-Temperatur oder darunter liegend abzukühlen, danach auf einen Temperaturbereich von AC3-Umwandlungstemperatur bis 950°C aufzuheizen und anschließend wieder zu kühlen.It has become known from US-A-4,933,024 to cool a rail from the rolling heat to A r3 temperature or below, then to heat to a temperature range of A C3 transformation temperature to 950 ° C and then to cool again.

Um ein gleichmäßiges Abkühlen von Fuß und Kopf der Schiene zu gewährleisten, wird in der DE 42 37 991 A1 vorgeschlagen, die Schiene mit dem Kopf nach unten hängend über das Kühlbett zu transportieren, und weitergehend in der US-PS 468 788, die nach unten hängenden Schienenköpfe in ein mit Wasser gefülltes Becken ganz oder teilweise einzutauchen, wobei sie gleichzeitig mittels Druckschrauben gegen ein festes Widerlager gedrückt werden.To ensure even cooling of the foot and head of the rail, is proposed in DE 42 37 991 A1, the rail with the head down hanging over the cooling bed to transport, and going on in the US PS 468 788, the down-hanging rail heads in a water-filled Immersion of the pelvis in whole or in part, at the same time by means of pressure screws be pressed against a fixed abutment.

Die bei der Abkühlung stattfindenden Gefügeumwandlungen werden in der EP 0 693 562 B1 beschrieben, wobei vorgeschlagen wird, dass das Walzgut mit einer durchschnittlichen Temperatur von höchstens 1100°C, mindestens jedoch 750°C gerade ausgerichtet wird, dann in Querrichtung gebracht und in einem ersten Kühlabschnitt mit gleicher örtlicher Kühlintensität auf eine Temperatur zwischen 860°C bis 5 bis 120°C über der Ar-Temperatur gekühlt, danach in einem zweiten Abkühlschritt mit gleicher, im Querschnitt gesehen mit umfänglich unterschiedlicher Kühlintensität, je nach Volumenanteil bezogen auf die Oberfläche, dem Walzgut in Längsrichtung Wärme entzogen und dadurch eine Gefügeumwandlung in eine martensitfreie feinperlitische Struktur erzeugt wird, wonach in einem Folgeschritt wieder mit gleicher örtlicher Kühlintensität die Abkühlung bis Raumtemperatur fortgesetzt wird.The microstructural changes taking place during cooling are described in EP 0 693 562 B1, wherein it is proposed that the rolling stock with a average temperature not exceeding 1100 ° C, but not less than 750 ° C is straightened, then transversely and in a first Cooling section with the same local cooling intensity to a temperature between 860 ° C to 5 to 120 ° C above the Ar temperature cooled, then in a second Cooling step with the same, seen in cross section with circumferentially different Cooling intensity, depending on the volume fraction based on the surface, the Walzgut in the longitudinal direction heat extracted and thereby a structural transformation is produced in a martensite-free fine perlitic structure, after which in a subsequent step again with the same local cooling intensity, the cooling to room temperature will continue.

Aus der DE-C-30 06 695 ist ein Verfahren bekannt, bei welchem die Abkühlung durch einen Zwischenschritt mit Wiederaufheizen unterbrochen und in dem zunächst durch Abkühlung der Schienen aus der Walzhitze im gesamten Querschnitt eine Umwandlung bewirkt, wonach der Schienenkopf, insbesondere durch induktive Erwärmung, reaustenitisiert und daran anschließend weiter gekühlt wird. Als Ergebnis erhält man ein feinlamellares perlitisches Gefüge, es besteht jedoch die Gefahr der Bildung unerwünschter Anteile an Bainit und Martensit im Gefüge.From DE-C-30 06 695 a method is known in which the cooling interrupted by an intermediate step with reheating and in the first by cooling the rails from the rolling heat in the entire cross section causes a conversion, after which the rail head, in particular by inductive Heating, reaustenitisiert and then further cooled. When The result is a fine lamellar pearlitic structure, but there is the Danger of formation of unwanted parts of bainite and martensite in the structure.

Um dieses zu vermeiden, wird in der EP 0 187 904 B1 neben dem Zusatz verschiedener Legierungsstoffe verfahrensmäßig vorgeschlagen, den Schienenkopf zunächst im Durchlauf in hinreichender Tiefe bis zu 50 mm mittels Brenner oder induktiv auf eine Austenitisierungstemperatur von 950 bis 1050°C aufzuheizen, anschließend mit Pressluft den Schienenkopf in einer ersten Abkühlstufe innerhalb von 10 bis 20 Sekunden auf 650 bis 600°C vor den Bereich der Perlitumwandlung zu kühlen und in einer zweiten Abkühlstufe mit gegenüber der ersten Stufe gedrosselter Luftmenge innerhalb von 2 bis 4 Minuten auf ca. 400°C bis zur Beendigung der Perlitumwandlung unter Bildung eines feinlamellaren perlitischen Gefüges abzukühlen. Anschließend wird der Schienenkopf erneut auf 600 bis 650°C für einen Zeitraum von 4 bis 6 Minuten erwärmt und sodann schnell auf unter 100°C abgeschreckt. To avoid this, in EP 0 187 904 B1 in addition to the addition of various Alloys proposed procedurally, the rail head first in the passage in sufficient depth up to 50 mm by means of burner or induction heating to an austenitizing temperature of 950 to 1050 ° C, then with compressed air, the rail head in a first cooling stage within from 10 to 20 seconds to 650 to 600 ° C before the area of pearlite conversion to cool and in a second cooling stage with respect to the first stage throttled Air volume within 2 to 4 minutes to about 400 ° C until the end the Perlitumwandlung to form a fine-lamellar pearlitic structure cool. Subsequently, the rail head is again set to 600 to 650 ° C for heated for a period of 4 to 6 minutes and then quickly to below 100 ° C. deterred.

Ausgehend von diesem Stand der Technik ist es Aufgabe der Erfindung, ein Verfahren anzugeben, durch das eine gezielte thermische Behandlung speziell während der Abkühlung des Schienenkopfes ermöglicht und mit einfachen Mitteln ein Gefüge- erzeugt wird, das einen feinlamellaren Perlit aufweist, der sich durch ein bestimmtes Härteniveau und damit verbunden durch eine hohe Verschieissfestigkeit auszeichnet und wobei während des Abkühlvorgangs insbesondere in den Randzonen des Schienenkopfes kein Bainit entsteht.Based on this prior art, it is an object of the invention, a method Specify through which a targeted thermal treatment specifically during the cooling of the rail head allows and with simple means Microstructure is produced, which has a fine-lamellar perlite, which is characterized by a certain hardness level and associated with a high resistance to abrasion characterized and wherein during the cooling process in particular in the Edge zones of the rail head no bainite arises.

Diese Aufgabe wird bei Schienen der vorstehend genannten Art durch die Maßnahmen des Anspruchs 1 gelöst, die gekennzeichnet sind durch die hintereinander angeordneten Verfahrensschritte:

  • a) Gezieltes Vorkühlen der Schiene aus der Walzhitze auf eine Kemtemperatur des Schienenkopfes von 750 °C bis 850 °C derart, dass eine zwischenzeitliche Unterkühlung der Randzone des Schienenkopfes und eine dortige vorzeitige Umwandlung verhindert wird,
  • b) Aufheizen der Randzone des Schienenkopfes auf mindestens Kerntemperatur,
  • c) Fertigkühlen der Schiene mit so hoher Wärmestromdichte, dass für die Kemzone des Schienenkopfes eine möglichst kurze t8/5-Zeit (Abkühlzeit von 800 bis 500°C im ZTU-Schaubild) erreicht wird.
    • This object is achieved with rails of the aforementioned type by the measures of claim 1, which are characterized by the successively arranged process steps:
  • a) Selective pre-cooling of the rail from the rolling heat to a core temperature of the rail head of 750 ° C to 850 ° C such that an interim supercooling of the edge zone of the rail head and a local premature conversion is prevented,
  • b) heating the edge zone of the rail head to at least core temperature,
  • c) finish cooling the rail with such a high heat flux density that for the core zone of the rail head the shortest possible t 8/5 time (cooling time of 800 to 500 ° C in the ZTU diagram) is achieved.

    • Durch diese erfindungsgemäß durchgeführten Verfahrensschritte mit zunächst gezielter Kühlung und daran anschließendem Wiederaufheizen, durch das die abgekühlten Randzonen mindestens wieder auf die Kemtemperatur aufgeheizt werden, wird es möglich, in der direkt anschließenden Kühlstrecke eine hohe Wärmestromdichte für die Schienen einzustellen, ohne die Randzonen unter die Bainit-Starttemperatur zu kühlen. Dabei kann gleichzeitig sichergestellt werden, dass für die Kernzone eine möglichst kurze t8/5-Zeit erreicht wird: Dies bedeutet insbesondere, dass der gesamte Schienenkopf gerade so schnell in die Umwandlungszone gekühlt wird, dass das gewünschte feinlamellare Perlitgefüge erzeugt wird. By means of these process steps carried out according to the invention with initially targeted cooling and subsequent reheating by which the cooled edge zones are at least heated again to the core temperature, it becomes possible to set a high heat flux density for the rails in the directly adjacent cooling section without the edge zones below the bainite Start temperature to cool. It can be ensured at the same time that the shortest possible t 8/5 time is achieved for the core zone: This means, in particular, that the entire rail head is cooled just as quickly into the conversion zone that the desired fine-lamellar pearlite structure is produced.

    Eine zwischenzeitliche Unterkühlung der Randzone und eine dortige vorzeitige Umwandlung wird somit verhindert und die Entstehung von Bainit vermieden. Gleichzeitig wird das Temperaturprofil des Schienenkopfes vor Eintritt in die abschließende Kühlstrecke homogenisiert, so dass auch die Kernzone des Schienenkopfes in ein ähnlich feinlamellares perlitisches Gefüge wie in der Randzone umgewandelt wird.An intermediate subcooling of the border zone and a premature one there Conversion is thus prevented and the formation of bainite avoided. At the same time the temperature profile of the rail head before entering the final Homogenized cooling section, so that the core zone of the rail head in a similar fine-lamellar pearlitic structure as in the marginal zone is converted.

    Ohne die erfindungsgemäße Verfahrensweise müsste die Kühlstrecke mit einer deutlich geringeren Wärmestromdichte betrieben werden, bzw. die einzustellende Wärmeübergangszahl wäre ca. 30 bis 40 % niedriger anzusetzen, um die Bainit-Bildung in den Randzonen des Schienenkopfes zu vermeiden. Hierdurch würden sich dann für den Kembereich eine erheblich längere t8/5-Zeit, ein größerer Lamellenabstand und damit verbunden geringere Härtewerte im Perlitgefüge ergeben.Without the procedure according to the invention, the cooling section would have to be operated with a significantly lower heat flux density, or the heat transfer coefficient to be set would be about 30 to 40% lower in order to avoid bainite formation in the edge zones of the rail head. As a result, a considerably longer t 8/5 time, a greater fin spacing and thus associated lower hardness values in the pearlite structure would then result for the core area.

    Das gezielte Vorkühlen auf eine Kemtemperatur des Schienenkopfes von 750 bis 850°C kann gemäß der Erfindung durch Abkühlen an Luft mit natürlicher Konvektion oder forciert mit Hilfe von Ventilatoren erfolgen. Es ist aber auch möglich, mit Hilfe von Düsen mit einem Wasser-Luft-Gemisch (Aerosol-Kühlung) zu kühlen, wobei diese Kühlung vorzugsweise auf einem Querschlepper mit entsprechender Anzahl von Liegeplätzen vorgenommen wird.The targeted pre-cooling to a core temperature of the rail head from 750 to 850 ° C can according to the invention by cooling in air with natural convection or forced with the help of fans. But it is also possible with To cool the help of nozzles with a water-air mixture (aerosol cooling), this cooling preferably on a cross tractor with appropriate Number of moorings is made.

    Während des Abkühlvorgangs wird die Oberflächentemperatur beispielsweise an der Schienenkopfmitte berührungslos mit Hilfe eines Pyrometers gemessen. Die hier ermittelte Randzonentemperatur liegt dann je nach der Abkühlart und Intensität ca. 30 bis 60°C unterhalb der noch vorhandenen Kemtemperatur.For example, during the cooling process, the surface temperature becomes the rail head center measured without contact using a pyrometer. The The boundary zone temperature determined here then depends on the type of cooling and intensity about 30 to 60 ° C below the still existing Kemtemperatur.

    Gemäß einer vorteilhaften Ausgestaltung der Erfindung wird die Temperatur des Schienenkopfes während der gesamten thermischen Behandlung, ausgehend vom Eintritt in die Vorkühleinrichtung bis zum Verlassen der Fertigkühleinrichtung gemessen. Die gemessenen Werte werden in eine Mess- und Regeleinrichtung eingespeist und dienen zur Steuerung der einzelnen durchzuführenden Verfahrensschritte, einschließlich der der Fertigkühlung vorgeschalteten Aufheizung. According to an advantageous embodiment of the invention, the temperature of Rail head during the entire thermal treatment, starting from entering the Vorkühleinrichtung until leaving the Fertigkühleinrichtung measured. The measured values are transferred to a measuring and control device fed and serve to control the individual process steps to be performed, including heating upstream of the final cooling.

    Eine schematisierte Anlage zur thermischen Behandlung nach dem Walzprozess einer beispielhaften Schiene ist nachfolgend in schematischen Zeichnungsfiguren dargestellt.A schematic system for thermal treatment after the rolling process An exemplary rail is shown below in schematic drawing figures shown.

    Es zeigen:

    Fig.1
    eine Schiene in Querschnitt,
    Fig. 2
    eine thermische Behandlungsanlage als Ablaufschema.
    Show it:
    Fig.1
    a rail in cross-section,
    Fig. 2
    a thermal treatment plant as a flowchart.

    In Figur 1 ist der Querschnitt einer Schiene 1 dargestellt. Die Schiene 1 besteht aus Profilteilen unterschiedlicher Masse, dem Schienenkopf 2 mit Randzone 5 und Kernzone 6, dem Mittelteil 3 und dem Schienenfuß 4. Die Randzone 5 des Schienenkopfes 2 ist in Fig. 1 gestrichelt dargestellt; es ist der Bereich, der primär durch gezielte thermische Behandlung in ein feinlamellares Perlitgefüge umgewandelt werden soll, ohne dass bei der thermischen Behandlung in dieser Randzone bzw. in diesen Bereich 5 Bainit entsteht.FIG. 1 shows the cross section of a rail 1. The rail 1 is made from profile parts of different mass, the rail head 2 with edge zone 5 and Core zone 6, the middle part 3 and the rail foot 4. The edge zone 5 of the rail head Fig. 2 is shown in phantom in Fig. 1; it is the area that is primarily through targeted thermal treatment converted into a fine-lamellar pearlite structure is to be, without that in the thermal treatment in this edge zone or 5 bainite is created in this area.

    In Figur 2 ist eine schematisierte Anlage 10 zur Durchführung der thermischen Behandlung nach der Erfindung dargestellt. Die Anlage 10 besteht - in der Walzlinie x-x hinter dem letzten Walzgerüst 11 hintereinander angeordnet - aus einer Vorkühleinrichtung 12, einer vorzugsweise induktiven Aufheizvorrichtung 13 und einer Fertigkühleinrichtung 14, die von der Schiene 1 nach ihrem Austritt aus dem Walzgerüst 11 nacheinander durchlaufen werden. Die Steuerung der thermischen Behandlung - umfassend die Intensität der Kühlung bzw. der Aufheizung sowie die Durchlaufgeschwindigkeit durch die einzelnen Anlagenteile 12, 13, 14, geschieht in Abhängigkeit von der jeweils gemessenen Temperatur durch eine Mess- und Regeleinrichtung 15, die über entsprechende Leitungen 16, 17, 18 für die Temperaturmesswerte und die Steuersignale mit den jeweiligen Anlagenteilen 12, 13, 14 verbunden sind.In Figure 2 is a schematic system 10 for carrying out the thermal Treatment according to the invention shown. The plant 10 is - in the rolling line x-x behind the last rolling mill 11 arranged one behind the other - from a Pre-cooling device 12, a preferably inductive heating device 13 and a Fertigkühleinrichtung 14, of the rail 1 after its exit from the Roll stand 11 are passed through one after the other. The control of the thermal Treatment - includes the intensity of cooling or heating as well the flow rate through the individual system parts 12, 13, 14, happens depending on the respective measured temperature by a measuring and control device 15, which via corresponding lines 16, 17, 18 for the Temperature measured values and the control signals with the respective installation parts 12, 13, 14 are connected.

    Das dargestellte Ausführungsbeispiel einer thermischen Behandlungsanlage kann selbstverständlich je nach Art und Größe der Schienen sowie der Art der gewählten Vor - und Fertigkühlung sowie dem Umfang der Mess- und Regeleinrichtung weitestgehend variiert werden, wenn die Einhaltung der hintereinander angeordneten erfindungsgemäßen Verfahrensschritte voll inhaltlich gewahrt bleibt. The illustrated embodiment of a thermal treatment plant can Of course, depending on the type and size of the rails and the type of the selected Pre - and final cooling as well as the scope of the measuring and control device be varied as far as compliance with the arranged one behind the other process steps of the invention is fully preserved content.

    BezugszeichenlisteLIST OF REFERENCE NUMBERS

    11
    Schienerail
    22
    Schienenkopfrailhead
    33
    Mittelteilmidsection
    44
    Schienenfußrail
    55
    Randzoneborder zone
    66
    Kemzonecore zone
    1010
    thermische Behandlungsanlagethermal treatment plant
    1111
    Walzgerüstrolling mill
    1212
    Vorkühleinrichtungprecooling
    1313
    Aufheizvorrichtungheating device
    14.14th
    FertigkühleinrichtungFinish cooling device
    1515
    Regeleinrichtungcontrol device
    1616
    Leitungmanagement
    1717
    Leitungmanagement
    1818
    Leitungmanagement

    Claims (6)

    1. A method for thermally treating rails (1), particularly hot-rolled carriageway or railway rails with profile sections of different mass, wherein rails (1) having the hot-forming temperature are subjected to a targeted thermal treatment and cooling of the profile sections such that a desired structure with increased strength is achieved in the profiled region, particularly in the rail head (2), characterized in that the following steps are carried out successively:
      a) targeted precooling of the rail (1) from the hot-forming temperature to a core temperature of the rail head (2) between 750°C and 850°C, namely such that an interim undercooling of the edge zone (5) of the rail head (2), as well as a premature transformation thereof, is prevented,
      b) heating the edge zone (5) of the rail head (2) to at least the core temperature,
      c) finish-cooling the rail (1) with such a high heat flow density that the shortest t8/5-time (cooling time from 800 to 500°C in the time-temperature transformation diagram) possible is achieved for the core zone (6) of the rail head (2).
    2. The method according to claim 1,
      characterized in that,
      during the finish-cooling step, the entire rail head (2) is cooled through the transformation zone so rapidly that a desired fine-lamellar perlite structure is produced without cooling the edge zone (5) below the bainite starting temperature.
    3. The method according to claim 1 or 2,
      characterized in that
      the precooling of the rail (1) is realized, depending on the cross-sectional dimensions of the rail, by means of air in the form of either natural convection cooling or forced cooling with the aid of fans or by means of a water-air mixture ejected from nozzles (aerosol cooling).
    4. The method according to claim 3,
      characterized in that
      the surface temperature is measured--preferably at the rail head center-in a contactless fashion, for example, with a pyrometer during the cooling phase of the precooling step.
    5. The method according to claim 4,
      characterized in that
      the surface temperature--preferably at the rail head center--is not only measured during the precooling step, but also during the heating and the finish-cooling step.
    6. The method according to claim 4 or 5,
      characterized in that
      the measured temperature values are used by a measuring and control unit (15) for controlling the course in time and the intensity of the entire thermal treatment of the rail (1) in the individual steps.
    EP02777151A 2001-09-29 2002-09-19 Method for thermal treatment of rails Expired - Lifetime EP1432835B1 (en)

    Applications Claiming Priority (3)

    Application Number Priority Date Filing Date Title
    DE10148305A DE10148305A1 (en) 2001-09-29 2001-09-29 Process and plant for the thermal treatment of rails
    DE10148305 2001-09-29
    PCT/EP2002/010512 WO2003028912A2 (en) 2001-09-29 2002-09-19 Method and system for thermal treatment of rails

    Publications (2)

    Publication Number Publication Date
    EP1432835A2 EP1432835A2 (en) 2004-06-30
    EP1432835B1 true EP1432835B1 (en) 2005-06-08

    Family

    ID=7700912

    Family Applications (1)

    Application Number Title Priority Date Filing Date
    EP02777151A Expired - Lifetime EP1432835B1 (en) 2001-09-29 2002-09-19 Method for thermal treatment of rails

    Country Status (10)

    Country Link
    US (1) US7416622B2 (en)
    EP (1) EP1432835B1 (en)
    JP (1) JP4317749B2 (en)
    CN (1) CN1263873C (en)
    AT (1) ATE297474T1 (en)
    AU (1) AU2002338735A1 (en)
    DE (2) DE10148305A1 (en)
    ES (1) ES2243768T3 (en)
    RU (1) RU2272080C2 (en)
    WO (1) WO2003028912A2 (en)

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    DE102006030699B4 (en) 2006-06-30 2014-10-02 Daimler Ag Cast steel piston for internal combustion engines
    CN100482812C (en) * 2006-09-12 2009-04-29 攀枝花钢铁(集团)公司 Rail heat processing method and rail heat processing unit
    ITMI20072244A1 (en) * 2007-11-28 2009-05-29 Danieli Off Mecc DEVICE FOR HEAT TREATMENT OF RAILS AND ITS PROCESS
    JP4757957B2 (en) * 2008-10-31 2011-08-24 新日本製鐵株式会社 Perlite rail with excellent wear resistance and toughness
    AU2010216990B2 (en) * 2009-02-18 2015-08-20 Nippon Steel Corporation Pearlitic rail with excellent wear resistance and toughness
    ES2716881T3 (en) 2009-06-26 2019-06-17 Nippon Steel Corp Steel rail with high carbon content, based on perlite, which has excellent ductility and production process
    CA2801245C (en) * 2010-06-04 2015-04-28 Csx Transportation Process and apparatus for rail restoration and rail manufacture using welding
    RU2447163C1 (en) 2010-08-10 2012-04-10 Общество С Ограниченной Ответственностью "Исследовательско-Технологический Центр "Аусферр" Method of metal structure alloy thermal treatment
    RU2487177C2 (en) * 2011-07-28 2013-07-10 Общество С Ограниченной Ответственностью Научно-Производственное Предприятие "Томская Электронная Компания" Method and installation for thermal treatment of rails
    RU2484148C1 (en) * 2011-10-27 2013-06-10 Общество С Ограниченной Ответственностью Научно-Производственное Предприятие "Томская Электронная Компания" Method and device for thermal treatment of rails
    US10214795B2 (en) 2013-03-28 2019-02-26 Jfe Steel Corporation Rail manufacturing method and manufacturing equipment
    JP6311678B2 (en) * 2014-09-24 2018-04-18 Ｊｆｅスチール株式会社 Rail manufacturing method and manufacturing apparatus
    US10286460B2 (en) 2017-04-07 2019-05-14 Robert J. Murphy Single-pass, single-radial layer, circumferential-progression fill-welding system, apparatus and method for refurbishing railway and other transit rails
    CN107520529B (en) * 2017-08-31 2019-10-11 攀钢集团研究院有限公司 The method of the mobile Flash Butt Welding of 136RE+SS heat-treated rail
    CN113403466A (en) * 2021-05-20 2021-09-17 包头钢铁（集团）有限责任公司 Production method for eliminating steel rail decarburized layer structure abnormality

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    Also Published As

    Publication number Publication date
    CN1561399A (en) 2005-01-05
    WO2003028912A3 (en) 2003-09-12
    EP1432835A2 (en) 2004-06-30
    US7416622B2 (en) 2008-08-26
    RU2272080C2 (en) 2006-03-20
    ATE297474T1 (en) 2005-06-15
    RU2004113116A (en) 2005-05-20
    DE50203370D1 (en) 2005-07-14
    AU2002338735A1 (en) 2003-04-14
    ES2243768T3 (en) 2005-12-01
    JP2005504174A (en) 2005-02-10
    JP4317749B2 (en) 2009-08-19
    CN1263873C (en) 2006-07-12
    DE10148305A1 (en) 2003-04-24
    US20040231763A1 (en) 2004-11-25
    WO2003028912A2 (en) 2003-04-10

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