EP0234204A2 - Procédé et dispositif pour dresser un rail du chemin de fer dans une dresseuse à rouleaux - Google Patents

Procédé et dispositif pour dresser un rail du chemin de fer dans une dresseuse à rouleaux Download PDF

Info

Publication number
EP0234204A2
EP0234204A2 EP87100231A EP87100231A EP0234204A2 EP 0234204 A2 EP0234204 A2 EP 0234204A2 EP 87100231 A EP87100231 A EP 87100231A EP 87100231 A EP87100231 A EP 87100231A EP 0234204 A2 EP0234204 A2 EP 0234204A2
Authority
EP
European Patent Office
Prior art keywords
rail
rollers
roller
straightening
last
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP87100231A
Other languages
German (de)
English (en)
Other versions
EP0234204A3 (fr
Inventor
Wilhelm Dr.-Ing. Heller
Reinhard Dr.-Ing. Schweitzer
Gerfried Dipl.-Ing. Vanino
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Krupp Stahl AG
Original Assignee
Krupp Stahl AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Krupp Stahl AG filed Critical Krupp Stahl AG
Publication of EP0234204A2 publication Critical patent/EP0234204A2/fr
Publication of EP0234204A3 publication Critical patent/EP0234204A3/fr
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D3/00—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts
    • B21D3/02—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts by rollers
    • B21D3/05—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts by rollers arranged on axes rectangular to the path of the work

Definitions

  • the invention relates to a method for straightening a railroad track in a roller straightening machine according to the preamble of the main claim.
  • the invention further comprises a roller straightening machine suitable for carrying out the method.
  • Rails produced by hot rolling rail steels in appropriately calibrated rolls cool in air to room temperature after rolling on cooling beds.
  • the rails bend when they cool down. In order to meet the high flatness requirements for the running surface, the rails must therefore be straightened.
  • the rail When straightening in roller straightening machines, the rail is subjected to opposing bending deformations by means of alternating individual bends over head and foot as it passes through the staggered upper and lower rollers, which forces each cross-section of the rail to undergo a path that reverses several times in its incline, alternating maxima in contact of the rail foot with the lower rollers and minima when the rail head comes into contact with the upper rollers.
  • Two top rollers and the associated bottom roller and two bottom rollers or the associated center top roller are each referred to as a triangle.
  • the maxima and minima that occur with the opposite bending deformations in the continuous path are brought about by positioning the lower rollers against the foot of the rail, with a lower roller adjustment decreasing towards the outlet side being provided according to the prior art. If a rail passes through the roller system with such a normal adjustment of the lower rollers, then it experiences alternating bends or curvatures up and down with maxima and minima until the desired flatness is finally achieved. Since the rail cross-section is plastically formed by the alternating opposing bending deformations when the rolls are straightened, but the shape changes are different over the cross-section, internal stresses arise in the rails oriented in this way.
  • the residual stresses on the running surface and on the underside of the rails are positive in the longitudinal direction, ie they lie Tensile stresses that are opposed by residual compressive stresses in the web.
  • the residual stresses increase with increasing strength of the rail material.
  • the process for straightening rails in a 9-roll machine (seven straightening rolls plus entry and exit rolls) and the residual stresses that occur when straightening the rails are described in detail in DE-Z Stahl und Eisen 105 (1985), No. 25-26 , Pages 1451 - 1456, esp.pictures 9 and 10 on page 1455.
  • the longitudinal tensile stresses for a UIC 60 rail reach 90 A (strength: 950 N / mm 2 ) in the head up to 200 N / mm 2 and in the base up to 260 N / mm2, for a UIC 60 rail in the S grade 1200 (strength: 1250 N / mm 2 ) in the head up to 250 N / mm 2 and in the foot up to 400 N / mm2.
  • the elastic strains of the head and foot correspond to the tensile residual stresses to be measured there.
  • the equilibrium is maintained by elastic compression of the web in accordance with the compressive residual stresses to be measured there.
  • the high residual tensile stresses affect the structural strength and the break resistance of the rails. Although they are converted to residual compressive stresses on the running surface during operation, they remain on the underside of the foot.
  • the directional effect is achieved in such a way that the rail is first strongly bent with the head in the pull zone by appropriately adjusting the first lower roller. Starting from this state of curvature, the rail is then bent with decreasing amounts with decreasing amounts of the second and third lower rollers by successive action of upper and lower rollers (directional triangles) with the foot or head in the pull zone until it is straight.
  • the common tangent to the top rollers specifies the desired trajectory in relation to the rail head. In this way, good results can be achieved with regard to the straightness of the rails, but only have very little influence on the longitudinal residual stresses in the foot. It is an object of the present invention to further develop the method of the type described above for the roller straightening of railroad tracks in such a way that the longitudinal tensile stresses in the rail foot, which determine the break resistance of the rail in operational use, are decisively reduced.
  • the rail follows an overall curved continuous path with the center of curvature below the rail foot and is bent in such a way that the minima of the rail that each rail section in the straightening machine on its way to passes through the last directional triangle, is the corner point of an imaginary polyline that rises on the inlet side and falls to the last directional triangle and the maxima are above the polygonal line, and that each rail section with an end curvature to be removed by the last directional triangle with a radius of 15 - 60 m into the last directional triangle comes in.
  • each section of the rail thus describes an arc directed upwards, limited by the pressure on the top rollers.
  • This curve is modulated by the individual bends (maxima and minima) of the continuous path.
  • the necessary adjustments of the middle upper rollers and the lower rollers are selected taking into account the spring back of the rail so that the rail receives a constant end curvature before the rail enters the last directional triangle.
  • the radius of curvature is 15 - 60 m depending on the rail quality and the intended directional effect.
  • This end curvature which is constant on the last section of the polygon, is converted into a straight track of the rail in the last directional triangle, formed by the last upper roller, the last lower roller and the outfeed roller.
  • the arc of the rail continuous path curved toward the top rollers is preferably designed in such a way that the rail section with constant end curvature and the minima of the individual bends lie on a common circular arc.
  • the middle top rollers are set an equal amount higher than the top and bottom rollers.
  • the upwardly curved arc of the rail pass can be designed such that the minima of the individual bends lie on a circular arc with a larger radius than the radius of the end curve.
  • the last maximum of the individual bends must be set accordingly before the rail enters the last directional triangle. The setting is selected taking into account the springback so that the deflection of the upwardly curved rail in the range between this maximum and the last minimum corresponds to the desired constant end curvature.
  • rails oriented in accordance with the invention surprisingly have very low longitudinal tensile stresses on the underside of the foot, as will be explained in the examples below.
  • the curvature of the rail path that is essential for the method according to the invention, curved upward to modulate the individual deflections due to the adjustment of the lower rollers, with constant end curvature before entering the last directional triangle can also be achieved if a smaller diameter is provided for the two middle upper rollers than the diameter of the outer top rollers, with the axes of the top rollers lying in the same plane.
  • the rail receives the required curvature over the rail head, passing into a uniform end curvature before it is bent into the required straight line by the directional triangle on the outlet side.
  • very low longitudinal tensile stresses in the rail base are achieved.
  • roller straightening machines with the features of claims 4 to 6 are suitable for carrying out the method according to the invention.
  • roller straightening machine With the roller straightening machine according to claims 4 and 5, it is possible to set the respective curvature of the upward curved trajectory of the rail according to the desired tension conditions in the rail foot within certain limits.
  • a roller straightener with the features of claim 6, according to which the middle top rollers have a smaller diameter than the outer top rollers, the radius of curvature of the rail pass is determined by the diameter of the middle rollers binding.
  • Such a machine can, however, be used advantageously where rails of constant quality and dimension are to be straightened. Then you can choose the diameter of the middle rollers from the outset so that the optimal judging result is guaranteed.
  • FIG. I a 9-roll straightening machine is shown in which the two middle upper rolls are adjustable in height. This representation is associated with FIG. 2, a representation of the curved rail path over the individual directional triangles predetermined by the rollers.
  • FIG 3 shows a further 9-roll straightening machine in which the middle upper rolls have a smaller diameter than the two outer upper rolls.
  • FIG. 4 shows a representation of the upward curved path of the rail through the straightening machine according to FIG. 3.
  • roller straightening machine R 1 In the case of Fig . 1 schematically shown roller straightening machine R 1 , four upper rollers 1, 3, 5 and 7 and a lower inlet roller E, three lower straightening rollers 2, 4 and 6 and a lower outlet roller A are mounted in a machine stand 8.
  • the middle top rollers 3 and 5 are height adjustable. In this example, all rollers have a diameter of 950 mm. The distance between the top rollers on the one hand and the bottom rollers on the other is 1,500 mm, based on the roller axes.
  • the lower rollers 2, 4 and 6 are each centered on the corresponding upper rollers 1, 3, 5 and 7.
  • the lower rollers 2, 4 and 6 as well as the inlet roller E and the outlet roller A are also adjustable in height.
  • All top rollers are driven by drive means, not shown.
  • a rail 9 is directed between the upper rollers and the lower rollers.
  • the rail rests with its head 9a on the upper rollers and with its foot 9b on the lower rollers.
  • the middle upper rollers 3 and 5 are raised by an equal amount of 73 mm compared to the straight connection between the contact lines of the first upper roller 1 and the fourth upper roller 7 with the rail head 9a.
  • the continuous rail describes a (imaginary) polygon P with the corner points 1 ', 3', 5 ', 7'.
  • the lower rollers are positioned above the sides of the polyline P upwards.
  • the lower roller 2 is set 22 mm higher, so that the (imaginary) polygon path 1'-3 'is bent upwards. This deflection gives the first maximum 2 'of the bending of the rail.
  • the lower roller 4 is set 18 mm higher than the polygon segment 3'-5 '(maximum 4'), the lower roller 6 is 15 mm higher than the polygon segment 5'-7 '(maximum 6').
  • FIG. 3 shows another roller straightening machine R 2 . It corresponds essentially to the roller straightening machine R 1 described in FIG. 1 .
  • the reference numerals, as mentioned in Fig. 1, are therefore retained.
  • the difference to the roller straightener R 1 is that in the roller straightener R 2 the middle upper rollers 3 and 5 have fixed axles that are in line with the axes of the upper rollers 1 and 7.
  • the diameter of the upper rollers 3 and 5 is smaller than the diameter of the outer upper rollers 1 and 7. In this example, it is 930 mm compared to 950 mm of the rollers 1 and 7.
  • a UIC 60 rail with a height of 172 mm is straightened.
  • the lower roller 2 is set 22 mm higher than the polygon path 1'-3 '(maximum 2').
  • the lower roller 4 is raised by 8 mm (maximum 4 ') beyond the polygon path 3'-5'.
  • the lower roller 6 is raised by 20 mm beyond the polygon path 5'-7 '(maximum 6').
  • the dashed lines denote the spreading area according to the usual roller straightening, while the dash-dotted lines limit the spreading area which results in the footing area when straightening according to the invention.
  • the pre-curvature of the rail with a constant final curvature before entering the last directional triangle is of crucial importance for the method according to the invention.
  • the splint still has the residual stress state with high longitudinal tensile stresses in the foot.
  • the upward curved rail is then straightened in the last triangle and stretched so permanently in the foot that the total length of the rail foot is increased and the length of the almost undeformed rail web is adjusted again.
  • length compensation by means of elastic expansions or corresponding tensile residual stresses is no longer the same as in conventional roller straightening, so that the longitudinal tensile stresses in the foot are consequently zero or close to zero.
  • the profile S 49 with a section modulus of 240 cm 3 and a meter mass of 49 kg / m can be used without loss of long-term load-bearing capacity even in the event of corrosion and the notches made with it.
  • the advantages in terms of fracture safety according to fracture mechanical assessment are just as significant.
  • the linear elastic fracture mechanics describes the conditions under which a component breaks brittle starting from an already existing crack. It can be used on rails. Thereafter, the safety against breakage of splints increases if a crack as deep as possible is borne before the breakage occurs with the same external stress.
  • the usual roller-oriented UIC 60 rail in quality 90 A was subjected to a permanent crack of 9 mm in the fatigue test before it broke brittle at an upper tension of 205 N / mrn2.
  • roller-oriented splint according to the invention with 28 mm suffered a permanent tear three times as deep before the break occurred at the same upper tension.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Straightening Metal Sheet-Like Bodies (AREA)
  • Wire Processing (AREA)
EP87100231A 1986-02-21 1987-01-10 Procédé et dispositif pour dresser un rail du chemin de fer dans une dresseuse à rouleaux Withdrawn EP0234204A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19863605648 DE3605648A1 (de) 1986-02-21 1986-02-21 Verfahren und vorrichtung zum richten einer eisenbahnschiene in einer rollenrichtmaschine
DE3605648 1986-02-21

Publications (2)

Publication Number Publication Date
EP0234204A2 true EP0234204A2 (fr) 1987-09-02
EP0234204A3 EP0234204A3 (fr) 1989-08-30

Family

ID=6294659

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87100231A Withdrawn EP0234204A3 (fr) 1986-02-21 1987-01-10 Procédé et dispositif pour dresser un rail du chemin de fer dans une dresseuse à rouleaux

Country Status (2)

Country Link
EP (1) EP0234204A3 (fr)
DE (1) DE3605648A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0976469A2 (fr) 1998-07-27 2000-02-02 Institut für Verformungskunde und Hüttenmaschinen Procédé de redressage linéaire
CN102049434B (zh) * 2009-11-06 2013-10-23 攀钢集团攀枝花钢铁研究院有限公司 矫直辊、用于矫直钢轨的设备和钢轨轧制方法

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10053933B4 (de) * 2000-10-31 2005-01-27 Thyssen Krupp Gleistechnik Gmbh Verfahren zum Richten einer Schiene
CN103157702B (zh) * 2013-03-23 2016-09-07 鞍钢股份有限公司 一种重轨端部弯曲的矫直控制方法
CN110899382B (zh) * 2019-10-30 2021-06-15 太原科技大学 一种带外横向筋的薄壁筒形件弧段的展开矫直设备
CN110899383B (zh) * 2019-10-30 2021-06-15 太原科技大学 一种带外横向筋的薄壁筒形件弧段的展开矫直方法
CN117139420B (zh) * 2023-10-31 2023-12-29 潍坊特钢集团有限公司 一种热轧圆钢的校直装置

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0976469A2 (fr) 1998-07-27 2000-02-02 Institut für Verformungskunde und Hüttenmaschinen Procédé de redressage linéaire
CN102049434B (zh) * 2009-11-06 2013-10-23 攀钢集团攀枝花钢铁研究院有限公司 矫直辊、用于矫直钢轨的设备和钢轨轧制方法

Also Published As

Publication number Publication date
DE3605648A1 (de) 1987-08-27
EP0234204A3 (fr) 1989-08-30

Similar Documents

Publication Publication Date Title
DE102008024013B3 (de) Verfahren und Vorrichtung zum Richten eines Metallbandes
DE102013106243C5 (de) Verfahren und Vorrichtung zum Streckbiegerichten von Metallbändern
EP0745441B1 (fr) Méthode et appareil pour la correction de la courbure latérale d'une bande métallique laminée, spécialement d'une bande métallique d'une épaisseur de 0,5 mm jusqu'a 2,0 mm
EP0296317B1 (fr) Procédé et dispositif pour cintrer une tôle
DE4207297A1 (de) Verfahren und vorrichtung zum richten von h-foermigen traegerprofilen
EP0234204A2 (fr) Procédé et dispositif pour dresser un rail du chemin de fer dans une dresseuse à rouleaux
DE102004003681A1 (de) Biegevorrichtung mit Pendelwalzrollen
EP1448323B1 (fr) Dispositif de fabrication d'un tube
DE1301295B (de) Verfahren und Vorrichtung zum AEndern der Spannungsverteilung ueber die Bandbreite beim Walzen von Band unter Zug
DE10053933B4 (de) Verfahren zum Richten einer Schiene
WO2011082881A2 (fr) Cage de laminoir et procédé pour faire fonctionner une cage de laminoir
DE3308616C2 (de) Verfahren und Maschine zum Richten von Blech
DE4024794A1 (de) Verfahren und vorrichtung zum richten von metallbaendern im durchlauf
DE102011121512A1 (de) Winkelwalzen
DE202019005662U1 (de) Richtaggregat für eine Walzen-Richtmaschine
DE2750752B2 (de) Verfahren und Vorrichtung zum Richten und zur Verbesserung der Qualitatseigenschaften von Metallbändern, insbesondere Elektrobändern
DE69924466T2 (de) Abstreifvorrichtung für flüssigkeiten
AT409230B (de) Verfahren zum linearrichten
DE3250083C2 (de) Gerichtete Eisenbahnschienen
EP4259355A1 (fr) Agencement, procédé et unité de dressage pour roulage de la région d'extrémité avec les deux extrémités de tubes fortement cintrés à l'aide d'une machine de roulage à trois cylindres
DE163330C (fr)
DE3337957A1 (de) Blechrichtmaschine
DE2337377A1 (de) Verfahren und vorrichtung zum richten unsymmetrischer geschweisster verbundprofile
DE1602468C3 (de) Verfahren und Vorrichtung zum Wechselbiegerichten von Blechen
DD145233A1 (de) Verfahren zum umformen von walzgut

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH DE ES FR GB IT LI LU NL SE

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH DE ES FR GB IT LI LU NL SE

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19900301

RIN1 Information on inventor provided before grant (corrected)

Inventor name: HELLER, WILHELM, DR.-ING.

Inventor name: VANINO, GERFRIED, DIPL.-ING.

Inventor name: SCHWEITZER, REINHARD DR.-ING.