EP0019737B1 - Laminoir utilisant un cylindre à convexité variable - Google Patents

Laminoir utilisant un cylindre à convexité variable Download PDF

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Publication number
EP0019737B1
EP0019737B1 EP19800102342 EP80102342A EP0019737B1 EP 0019737 B1 EP0019737 B1 EP 0019737B1 EP 19800102342 EP19800102342 EP 19800102342 EP 80102342 A EP80102342 A EP 80102342A EP 0019737 B1 EP0019737 B1 EP 0019737B1
Authority
EP
European Patent Office
Prior art keywords
roll
rolls
rolling mill
rolling
crown
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.)
Expired
Application number
EP19800102342
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German (de)
English (en)
Other versions
EP0019737A1 (fr
Inventor
Tetsuya Mukai
Chihiro Hayashi
Takeshi Masui
Kazuo Kondo
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.)
Nippon Steel Corp
Original Assignee
Sumitomo Metal Industries Ltd
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
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Application filed by Sumitomo Metal Industries Ltd filed Critical Sumitomo Metal Industries Ltd
Publication of EP0019737A1 publication Critical patent/EP0019737A1/fr
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Publication of EP0019737B1 publication Critical patent/EP0019737B1/fr
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
    • B21B27/02—Shape or construction of rolls
    • B21B27/03—Sleeved rolls
    • B21B27/05—Sleeved rolls with deflectable sleeves
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/28—Control of flatness or profile during rolling of strip, sheets or plates
    • B21B37/30—Control of flatness or profile during rolling of strip, sheets or plates using roll camber control
    • B21B37/34—Control of flatness or profile during rolling of strip, sheets or plates using roll camber control by hydraulic expansion of the rolls
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/28—Control of flatness or profile during rolling of strip, sheets or plates
    • B21B37/38—Control of flatness or profile during rolling of strip, sheets or plates using roll bending

Definitions

  • the present invention relates to a multi-high rolling mill including at least one pair of work rolls and one or more back-up rolls, at least one of the rolls being a variable crown roll, wherein the extent of the crowning is controlled by means of a pressure medium.
  • work roll as used herein and in the claims is to be understood to mean a roll in direct contact with a material to be rolled and the term “back-up roll” is to be understood to mean a roll directly or indirectly supporting the work roll.
  • DE-A-1 452 009 describes variable crown backing rolls, which can be mounted, for example, in a four-high rolling mill.
  • Each backing roll consists of a solid cylindrical core or mandrel, mounted on the machine stand so as to be non-rotatable, which is surrounded by a rotatable roll sleeve, the outer circumferential surface of which acts as the back-up surface of the roll.
  • a pressurized fluid can be supplied to portions of the outer surface of the cylindrical core to provide a back-up pressure against the inner wall of the rotatable outer sleeve at positions along the line of contact with the work roll.
  • US-A-3 457 617 reports the proposal to subject the working rolls to preliminary bending by means of forces acting on the roll necks in such manner as to compensate the bending caused by the rolling force, but states that complete compensation is impossible because the rolling force produces a bending line different from that of the preliminary bending by the forces on the roll necks and that the whole roll stand must be of more robust design to withstand the additional forces.
  • a working roll having a variable camber is described. This roll has an annular cavity below its rolling surface which is filled with a liquid through a system of axial and radial channels formed within the roll. The camber can be controlled by varying the pressure of the liquid and adapted, by means of thickness gauges, automatically to the material being rolled. This roll is said to make it possible to use simple two-high rolling mills instead of expensive four-high rolling mills.
  • DE-A-1 602 200 describes a method for controlling the crown of working rolls during the rolling of metal strip and other materials in hot and cold rolling mills, wherein a hollow interior axial space of one or more of the rolls of a rollstand is filled with a highly pressurized fluid, the pressure of which is variable. Sudden rolling-pressure fluctuations can be detected by a pressure gauge and compensated automatically.
  • DE-A-2 507 233 describes the interposition of hydraulic elements between an inner core and a rotatable roll sleeve of a back-up roller to back up the pressure of the outer sleeve against the working rolls at positions at which the backing roller sleeve acts on the working rolls.
  • VC rolls Two-high rolling mills using conventional variable crown rolls (hereinafter referred to as VC rolls) have had several disadvantages, such as the work rolls being unable to withstand the high rolling load, the manufacture of roll sleeves of high hardness being difficult, the toughness of the sleeves being decreased as the requirement of higher surface hardness is fulfilled and shape defects being caused in the rolled strip in the neighbourhood of the pressure receiving sleeve end, so that these rolling mills, whilst suitable for light rolling such as temper rolling, were not suited for heavy load rolling such as common hot or cold rolling.
  • This object is achieved by providing roll benders between the work rolls and/or the back-up rolls to control the extent of crowning of the variable crown roll and the roll bending force, thereby controlling the sheet crown and the shape of the material being rolled.
  • the rolling mill of the present invention thus includes at least a pair of work rolls and one back-up roll in an arrangement which is at least three-high and mainly four high in a single stand or in tandem stands, as well as roll benders. It can be used for either hot or cold rolling.
  • the VC roll used is constructed so that its crowning is controllable by means of a fluid or viscous material introduced under pressure into a predetermined cavity defined between an arbor and a sleeve.
  • an annular cavity 3 is defined between an arbor 1 and a sleeve 2, to which a medium (for example, water, oil, grease or the like) under high pressure is applied from a medium pressurizing unit 4 through a conduit 11 provided in the arbor 1 so as to control the extent of crowning of the roll (that is, the extent of the diametrical expansion of the roll outer diameter) by regulating the pressure of the medium by means of the unit 4.
  • a medium for example, water, oil, grease or the like
  • the rolling mills of the present invention are of the types, for example, as shown in Figs. 2 to 4.
  • the rolling mills are, in principle, multi-high rolls mainly from three-high to six-high rolls, as shown in Figs. 2A to 2F, and most suitably four-high rolls, as shown in Fig. 2C. Accordingly, the present invention will be described hereinunder as being applied to the four-high rolling mill for the sake of simplicity, but it must be understood that application of the present invention is not limited thereto.
  • the rolling mill may be either of single stand, as shown in Fig. 3A, or of tandem stands, as shown in Fig. 3B. With respect to additional equipment, the rolling mill is provided with a roll bender J w or J B in the work roll W or back-up roll B thereof.
  • the basic construction of the rolling mill according to the present invention resides in, as shown with reference to the three-high mill for convenience' sake in Figs. 5A to 5G, the multi-high rolling mill in which at least one of the rolls is the VC roll (hatched in the drawing). Accordingly, the three-high rolling mill according to the present invention may take any of the roll combinations shown in Figs. 5A to 5G. Special effects achieved by this construction will become clear from the ensuing description.
  • the four-high rolling mill has, as shown in Figs. 6A to 6C, at least one VC roll (hatched in the drawing) in the back-up rolls.
  • the extent of crowning of the back-up rolls is first changed.
  • the change then exerts an influence on the work rolls to bend the entire shafts of the work rolls to thereby cause a substantially predetermined extent of change in the crown of the work rolls.
  • Sheet crown thickness distribution across the strip width
  • shape tests were peformed in the four-high rolling mill in which, as shown in Fig. 6A, the upper back-up roll is a VC roll of the size 200 mm in outer diameter and 460 mm in length, while the work roll is of the size 80 mm in outer diameter and 460 mm in length.
  • Fig. 12 shows the results of the sheet crown tests performed on an aluminum plate of 4 mm in thickness and 350 mm in width under a rolling load of 20 tons using the four-high rolling mill described above.
  • the marks O, 6, ⁇ and X denote oil pressures P' of the VC roll of 0, 165, 340, and 510 kg/cm l respectively.
  • the oil pressure of the VC roll increases, the axial deflection of the work rolls changes.
  • the sheet crown changes with the change in the axial deflection of the work rolls.
  • the sheet crown control effect was confirmed.
  • Fig. 13 shows the results of the shape tests performed on a cold rolled coil of 0.4 mm in thickness and 300 mm in width under fixed drafts using the same four-high rolling mill described above.
  • the marks O, 0, and A Indicate a reduction of 0.5, 1.0, and 14.5%, respectively.
  • the shape of the rolled material changes from wavy edges to center buckle and, under the predetermined reduction, good flatness is obtained at a specified oil pressure.
  • the four-high rolling mill has, as shown in Figs. 7A to 7C, at least one VC roll (hatched in the drawing) in the work rolls.
  • Fig. 14 shows the results of the sheet crown tests performed on an aluminum plate of 4 mm in thickness and 250 mm in width under the rolling load of 20 tons using the four-high rolling mill described above.
  • the marks O, 0, and X denote oil pressures P' of the VC roll of 0, 200, and 400 kg/cm 2 , respectively.
  • the curves of Fig. 14 show the similar tendency to those of Fig. 12.
  • Fig. 15 shows the results of the shape tests performed on a cold rolled coil of 0.4 mm in thickness and 300 mm in width under the reduction of 1% using the same four-high rolling mill with the oil pressure P' (kg/cm 2 ) of the VC roll changed.
  • the curves of Fig. 15 show the similar tendency to those of Fig. 13.
  • Figs. 16 and 17 show the results of the sheet crown and the shape tests, respectively, performed in a further embodiment of the present invention in which the VC roll is used in one of each of the back-up and the work rolls as shown in Figs. 8A and 8B.
  • the sizes of the rolls of the mills and the sizes and the quality of the specimens used in the tests of Figs. 16 and 17 are the same as those used in the tests of Fig. 14.
  • the marks O, 0, and X denote oil pressures P' (kg/cm 2 ) of the VC roll of 0, 100 and 200 kg/cm 2 , respectively.
  • the rolling load was 25 tons.
  • the marks 0 and ⁇ t denote a reduction of 3 and 15%, respectively.
  • VC rolls used in pair are of the same internal construction. As shown in Figs. 9 and 10, however, by intentionally making one of the VC rolls in pair different from the other in the variable crown construction (primarily the size of the cavity which is filled by the pressure medium), it is made possible to roll efficiently materials ranging in width radically without changing the rolls. That is, a material of large width is rolled by rolls of large width variable crown construction, a material of small width is rolled by rolls of small width variable crown construction, and a material of intermediate width is rolled by rolls of large width alone or in combination with the rolls of small width variable crown rolls.
  • the sheet crown and shape control system can be constructed by combining the VC rolls with a detector.
  • a rolling mill 21 is provided on the exit/entry side thereof with a sheet crown and shape detector 22, a detection signal of which is transmitted to a control unit 23 in which the detection signal is compared with the set value, to control the medium pressurizing unit 4 (see Fig. 1) of the VC roll provided in the rolling mill 21.
  • the detector is preferably of non-contact type.
  • Various instruments such as an X-ray thickness meter, a A-ray thickness meter, a flying micrometer and the like can be used as the sheet crown detector.
  • There are various types of the shape detector such as optical type, electromagnetic type, displacement-type, vibration-type, and the like.
  • the sheet crown control is performed within the range of the shape defect that is not disadvantageous to the rolling operation and the shape control is performed at the final pass.
  • the sheet crown is performed at the upstream stand and the shape- attended control is performed at the final stand.
  • the shape correction was performed by a work roll bender or a back-up roll bender.
  • the present invention uses a combination of the roll bender with the VC roll. The results of numerical experiments show that this construction provides unexpected multiplication effects as described below.
  • the rolling mill used in the experiments is, as shown in Fig. 18, a four-high mill in which the upper back-up roll B is a VC roll and a roll bender is provided between the work rolls W.
  • Table 1 shows the sizes of this rolling mill and the rolling conditions.
  • Figs. 19 to 21 show the results of tests performed on the relation between the work roll bending force J w (ton) and the bar crown when the oil pressure P' (kg/cm 2 ) applied to the VC roll in this rolling mill is varied stepwise.
  • Fig. 19 shows the results of the cold temper rolling of a material of 1200 mm in width under a rolling load of 500 tons.
  • the horizontal axis indicates the bending force J w (ton) of the work rolls and the vertical axis indicates the bar crown 6c (cm) at the position of 1/4 of width, while A denotes the conventional bending effect (19.2p), B denotes the effects of change in oil pressure of the VC roll only (31.3p), and C denotes the multiplication effect (51.6 ⁇ ) by the VC roll and the bender.
  • Fig. 20 shows the results of the cold tandem rolling of a material of 1000 mm in width under a rolling load of 900 tons.
  • Fig. 21 shows the results of the hot tandem rolling of a material of 1000 mm in width under a rolling load of 900 tons.
  • Table 3 shows the examples of application of the VC roll to a continuous finishing mill
  • application of it to a roughing mill is likewise effective.
  • its application to a roughing mill of a semi-continuous hot strip mill is effective not only in crown control but also in improvement in the crop less at the top or bottom of the strip.
  • the combination of the VC roll with the conventional roll bender provides an enlarged range of control.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Reduction Rolling/Reduction Stand/Operation Of Reduction Machine (AREA)
  • Control Of Metal Rolling (AREA)

Claims (4)

1. Laminoir à plusieurs cylindres comportant au moins deux cylindres de travail (W) et un ou plusieurs cylindres d'appui (B), l'un au moins des cylindres (B, W) étant un cylindre à bombement variable dans lequel le degré de bombement est réglé au moyen d'un fluide sous pression, caractérisé en ce que des cintreurs de cylindres (IB, lw) sont montés entre les cylindres de travail (W) et/ou les cylindres d'appui (B) pour régler le degré de bombement du cylindre à bombement variable et la force de cintrage des cylindres, réglant ainsi le bombé de la tôle et la forme du produit à laminer.
2. Laminoir à plusieurs cylindres selon la revendication 1, caractérisé en ce que deux cylindres d'appui (B) sont deux cylindres à bombement variable dont la structure diffère de l'un à l'autre.
3. Laminoir à plusieurs cylindres selon la revendication 1, caractérisé en ce que deux cylindres de travail (W) sont deux cylindres à bombement variable dont la structure diffère de l'un à l'autre.
4. Laminoir à plusieurs cylindres selon l'une quelconque des revendications 1 à 3, caractérisé en ce que le bombement des cylindres à bombement variable est réglé par un signal indicatif de la forme et/ou du bombé du produit à laminer.
EP19800102342 1979-05-24 1980-04-30 Laminoir utilisant un cylindre à convexité variable Expired EP0019737B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP64459/79 1979-05-24
JP6445979A JPS5926365B2 (ja) 1979-05-24 1979-05-24 可変クラウン・ロ−ルを用いた圧延機

Publications (2)

Publication Number Publication Date
EP0019737A1 EP0019737A1 (fr) 1980-12-10
EP0019737B1 true EP0019737B1 (fr) 1983-06-08

Family

ID=13258834

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19800102342 Expired EP0019737B1 (fr) 1979-05-24 1980-04-30 Laminoir utilisant un cylindre à convexité variable

Country Status (5)

Country Link
EP (1) EP0019737B1 (fr)
JP (1) JPS5926365B2 (fr)
AU (1) AU537257B2 (fr)
CA (1) CA1147990A (fr)
DE (1) DE3063658D1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3819303A1 (de) * 1988-06-03 1989-12-07 Mannesmann Ag Flachwalzwerk

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU546760B2 (en) * 1980-08-08 1985-09-19 Sumitomo Metal Industries Ltd. Tandem mill
JPS5773204A (en) * 1980-10-20 1982-05-07 Sumitomo Metal Ind Ltd Super-high pressure continuous control unit
JPS5816720A (ja) * 1981-07-20 1983-01-31 Sumitomo Metal Ind Ltd 圧延材の板クラウンと板形状の制御方法
JPS5832509A (ja) * 1981-08-18 1983-02-25 Sumitomo Metal Ind Ltd 圧延材の板クラウンと板形状の制御方法
AT373795B (de) * 1981-11-11 1984-02-27 Escher Wyss Ag Walzvorrichtung
JPS5935806A (ja) * 1982-08-24 1984-02-27 Sumitomo Metal Ind Ltd 圧延方法
JPS5954401A (ja) * 1982-12-17 1984-03-29 Ishikawajima Harima Heavy Ind Co Ltd 圧延方法
DE3342054C2 (de) * 1983-11-22 1986-01-30 Bwg Bergwerk- Und Walzwerk-Maschinenbau Gmbh, 4100 Duisburg Walze für Walzwerke
JPS60206511A (ja) * 1984-03-29 1985-10-18 Sumitomo Metal Ind Ltd 板形状制御方法及びその装置
WO1990000450A1 (fr) * 1988-07-11 1990-01-25 DAVID McKEE (POOLE) LIMITED Laminage de materiau en bande
US8277645B2 (en) 2008-12-17 2012-10-02 Jarvis Jr Ernest Automatic retractable screen system for storm drain inlets
DE102010029598A1 (de) 2010-06-01 2011-12-01 ACHENBACH BUSCHHüTTEN GMBH Stützwalze und damit ausgerüstetes Walzgerüst
CN113393753B (zh) * 2021-05-24 2022-08-16 攀钢集团攀枝花钢钒有限公司 钢轨半万能轧制金属流动平面演示控制方法
CN116159869B (zh) * 2023-01-04 2023-08-25 北京科技大学 具有局部边浪控制能力的变凸度工作辊辊形及设计方法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3355924A (en) * 1963-07-10 1967-12-05 Sendzimir Inc T Control of deflection in rolling mills and the like
DE1527606A1 (de) * 1966-01-19 1970-02-26 Bwg Bergwerk Walzwerk Arbeitswalze mit veraenderbarer Balligkeit
GB1149123A (en) * 1967-06-13 1969-04-16 Wtz Feikeramischen Ind Method and apparatus for regulating the profile of working rollers of rolling mills
DE1602155A1 (de) * 1967-09-29 1970-04-09 Siemag Siegener Maschb Gmbh Verfahren zum Ausgleich der Durchbiegung des Walzenballens von Walzwerkswalzen sowie Walzwerkswalze zur Ausuebung des Verfahrens
CH587689A5 (fr) * 1975-02-13 1977-05-13 Escher Wyss Ag
CH613134A5 (fr) * 1976-11-02 1979-09-14 Escher Wyss Ag

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3819303A1 (de) * 1988-06-03 1989-12-07 Mannesmann Ag Flachwalzwerk

Also Published As

Publication number Publication date
AU537257B2 (en) 1984-06-14
EP0019737A1 (fr) 1980-12-10
DE3063658D1 (en) 1983-07-14
JPS5926365B2 (ja) 1984-06-27
AU5690380A (en) 1980-11-27
CA1147990A (fr) 1983-06-14
JPS55156606A (en) 1980-12-05

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