US20010018840A1 - Strip rolling mill and strip rolling method - Google Patents

Strip rolling mill and strip rolling method Download PDF

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Publication number
US20010018840A1
US20010018840A1 US09/790,648 US79064801A US2001018840A1 US 20010018840 A1 US20010018840 A1 US 20010018840A1 US 79064801 A US79064801 A US 79064801A US 2001018840 A1 US2001018840 A1 US 2001018840A1
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US
United States
Prior art keywords
rolls
strip
support
work rolls
work
Prior art date
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Abandoned
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US09/790,648
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English (en)
Inventor
Mistuo Nihei
Kenichi Yasuda
Yukio Hirama
Minoru Igari
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.)
Hitachi Ltd
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Hitachi Ltd
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Filing date
Publication date
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Assigned to HITACHI, LTD. reassignment HITACHI, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HIRAMA, YUKIO, IGARI, MINORU, YASUDA, KENICHI, NIHEI, MISTUO
Publication of US20010018840A1 publication Critical patent/US20010018840A1/en
Abandoned legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B13/00—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories
    • B21B13/14—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories having counter-pressure devices acting on rolls to inhibit deflection of same under load; Back-up rolls
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B13/00—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories
    • B21B13/14—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories having counter-pressure devices acting on rolls to inhibit deflection of same under load; Back-up rolls
    • B21B13/145—Lateral support devices for rolls acting mainly in a direction parallel to the movement of the product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length

Definitions

  • the present invention relates to a strip rolling mill, and more particularly to a strip rolling mill and a strip rolling method suitable for high quality milling for a hard material and an ultra thin material using a small diameter work roll.
  • Japanese Patent Laid-Open No. Hei 1-262005 discloses a method in which divided rolls are not used, slide bearing pads which are brought into sliding contact directly with an entry side and a delivery side of a work roll in the horizontal direction are disposed, and a displacement in the horizontal direction is controlled by pressing the slide bearing pads to thereby carry out control in shape of strip.
  • Japanese Patent Laid-Open No. Hei 2-147108 and Japanese Patent Laid-Open No. Hei 10-230308 disclose a rolling mill having a horizontal direction support mechanism for supporting a work roll by hydrostatic bearings while interposing idle rolls therebetween without slidably supporting the work roll directly by slide bearing pads.
  • the stopper means is constituted by gap defining rolls which are brought into contact with the work roll at positions in the axial direction on outer sides of an area in correspondence with a maximum sheet width of strip substantially from the horizontal direction and functions to prevent the gap between the hydrostatic bearing and the idle roll from becoming less than the predetermined value.
  • Japanese Patent Laid-Open No. Hei 9-285804 disclose a technology in which a work roll is pressed and horizontally supported by both ends support rolls only at outer sides of a strip pass (outer sides of a maximum sheet width of strip) of the work roll whose contact positions is the same as those of the above-described gap defining rolls.
  • the gap defining rolls at the both end portions basically serve as stoppers for preventing horizontal movement of the work roll and accordingly, when rolling operation is not carried out, the gap defining rolls do not apply a press force to the both end portions of the work roll and a very small interval is present therebetween or the gap defining rolls are brought into slight contact with the both end portions of the work roll.
  • a strip rolling mill comprising: at least a pair of upper and lower work rolls for rolling strip; at least a pair of backup rolls for supporting the work rolls in an up and down direction and providing a rolling drive force thereto; at least pairs of both ends support rolls opposed to each other in a horizontal direction for pressing and sandwiching both end portions of the work rolls on outer sides of a width along which a maximum sheet width of the strip passes on barrel portions of the work rolls; and hydrostatic bearings for supporting, by hydraulic pressure, at least either one of an entry side and a delivery side of centers of the barrel portions of the work rolls substantially in a horizontal direction.
  • a strip rolling mill comprising: at least a pair of upper and lower work rolls for rolling strip; at least a pair of backup rolls for supporting the work rolls in an up and down direction and providing a rolling drive force thereto; at least pairs of both ends support rolls opposed to each other in a horizontal direction for pressing and sandwiching both end portions of the work rolls on outer sides of a width along which a maximum sheet width of the strip passes on barrel portions of the work rolls; and hydrostatic bearings for supporting, by hydraulic pressure via at least one or more of idle rolls, at least either one of an entry side and a delivery side of centers of the barrel portions of the work rolls substantially in a horizontal direction.
  • the bending of the work roll in the horizontal direction can effectively be shared by means of the both ends support rolls and the hydrostatic bearings to thereby surely support the backup roll, and even if the work roll is ground and the diameter is changed, the work roll can pertinently be supported always by the hydrostatic bearings via contact with the idle rolls.
  • a total support apparatus integrally formed by support portions for the both ends support rolls and support portions for the hydrostatic bearings are installed to be capable of adjusting the position of the work rolls in the horizontal direction at either one of the entry side and the delivery side of the work rolls as a reference side; and wherein on opposed sides of the work rolls, as pressing side, the total support apparatus are installed to be capable of pressing the work rolls in the horizontal direction opposedly to the reference side.
  • the work roll is preferably supported without applying extra load to the hydrostatic bearing on the side that receives the roll by rolling.
  • the strip rolling mill further comprises load detecting means provided at support portions for at least one of the both ends support rolls on at least one of the entry side and the delivery side and for at least one of the hydrostatic bearings.
  • the position of the hydrostatic bearing in the horizontal direction can be set and controlled such that the hydrostatic bearing can support the work roll by a pertinent support force.
  • the support force in the horizontal direction of the both ends support roll supporting portions on the reference side is controlled to be larger than a slip occurrence limit value between the work rolls and the both ends support rolls but to be smaller than a support limit value of the both ends support rolls; and wherein the press force of the both ends support rolls on the pressing side is controlled to be larger than the slip occurrence limit value between the work rolls and the both ends support rolls and to be as large as possible within a range equal to or smaller than the support limit value of the both ends support rolls.
  • the strip rolling mill further comprises means for variably controlling an effective length of the hydrostatic bearing to be substantially the same as a sheet width of the strip.
  • a strip rolling method of rolling strip by supporting the work rolls in the horizontal direction by means of the both ends support rolls and the hydrostatic bearings using the strip rolling mill according to (1) or (2).
  • FIG. 1 is a vertical sectional view of principal portions of a strip rolling mill according to a first embodiment of the present invention
  • FIG. 2 is a horizontal sectional view of principal portions of the strip rolling mill according to the first embodiment of the present invention
  • FIG. 3 is a view for explaining the force S in the horizontal direction exerted to a small diameter work roll
  • FIG. 4A is a model diagram of support for horizontal bending caused in a work roll by rolling and FIG. 4B illustrates a bending amount ⁇ caused in the work roll;
  • FIG. 5 is a diagram showing a change of axial bending ⁇ when rolling conditions such as a sheet width W and a work roll support system are changed;
  • FIG. 6 is a diagram representing a calculating result of reaction Rc of both ends supporting points, when rolling conditions such as the sheet width W and the work roll support system are changed, in a ratio thereof to a value (a 0 ) in the case of both ends simple support;
  • FIG. 7 is a view showing a constitution in which two or more of both ends support rolls are installed on one side of respective end portions of a work roll;
  • FIG. 8 is a view showing a constitution that changes an effective support length of a hydrostatic bearing in accordance with a sheet width
  • FIG. 9 is an explanatory view of the force S in the horizontal direction exerted to a work roll when there is a positional shift (offset) in a rolling pass direction between the work rolls and intermediate rolls supporting the work roll from an up and down direction;
  • FIG. 10 is a vertical sectional view of principal portions of a strip rolling mill according to a second embodiment of the present invention.
  • FIG. 11 is a horizontal sectional view of principal portions of the strip rolling mill according to the second embodiment of the present invention.
  • FIG. 12 is a vertical sectional view of principal portions of a strip rolling mill according to a third embodiment of the present invention.
  • FIG. 13 is a horizontal sectional view of principal portions of the strip rolling mill according to the third embodiment of the present invention.
  • FIG. 1 is a vertical sectional view of principal portions of a strip rolling mill 1 according to a first embodiment of the present invention and FIG. 2 is a horizontal sectional view of principal portions of the strip rolling mill 1 .
  • a pair of work rolls 3 and 4 to roll strip 2 are supported in the vertical direction by intermediate rolls 5 and 6 and backup rolls 7 and 8 .
  • the intermediate rolls 5 and 6 are connected to a motor, not illustrated, and the work rolls 3 and 4 are driven by the intermediate rolls 5 and 6 .
  • both ends support rolls 9 , 10 , 11 and 12 are installed on an entry side and a delivery side of respective end portions to be opposed to each other on outer sides of a width along which a maximum sheet width of the strip passes on barrel portions of the work roll 3 .
  • a rolling pass direction of the strip 2 is a direction directed from left to right.
  • a left side of the work roll 3 is defined as a rolling pass direction position setting side (hereinafter, referred to as reference side) of the work roll 3 and a right side opposed thereto is defined as a pressing side.
  • both ends support rolls 10 and 12 on the reference side are attached to both ends support roll position setting apparatuses 13 and 14 disposed in the horizontal direction with respect to the work rolls, and the both ends support roll position setting apparatuses 13 and 14 are fixed to housing posts 16 and 18 .
  • both ends support roll position setting apparatus 13 and 14 are provided with both end support force detecting apparatuses 19 and 20 which are load detecting means for detecting load from the work roll 3 so that a sum of load generated at both end portions of the work roll 3 and a press force from the both ends support rolls 9 and 11 opposed to each other can be detected.
  • hydrostatic bearings 23 and 24 at barrel center portions of the work rolls 3 and 4 on the reference side are disposed so that a fluid such as oil is supplied from a fluid pressure supply port 25 to the bearing portions, a gap is produced between the hydrostatic bearing 23 , and the work roll 3 to thereby float up the work roll 3 and the work roll 3 is supported in the horizontal direction in noncontact.
  • the hydrostatic bearings 23 and 24 are respectively installed at beams 29 and 30 having high rigidity and the rigid beams 29 and 30 are installed further to hydrostatic bearing position setting apparatuses 33 and 34 fixed to the housings 16 and 18 .
  • the hydrostatic bearing position setting apparatuses 33 and 34 set and control the gap between the hydrostatic bearing 23 and the work roll 3 to suitably support a work roll horizontal force generated when rolling operation. Further, the hydrostatic bearing position setting apparatuses 33 and 34 are provided with hydrostatic support force detecting apparatus 35 and 36 such that a support force of the hydrostatic bearing 23 can be detected.
  • both ends support roll pressing apparatus 37 and 38 are provided with both end pressing force detecting apparatuses 39 and 40 which are load detecting means such that a press force of the both ends support rolls on the pressing side can be detected.
  • both ends support roll pressing apparatuses 37 and 38 are cylinders in FIG. 2, a fixed type or a screw type may be adopted. In that case, it is necessary to use load cells or the like as the both end pressing force detecting apparatuses 39 and 40 .
  • hydrostatic bearings 21 and 22 are installed at barrel center portions of the work rolls 3 and 4 on the pressing side so that a fluid such as oil is supplied from a fluid pressure supply port 26 to the bearing portions, a gap is produced between the hydrostatic bearing 21 and the work roll 3 to thereby float up the work roll 3 , and the work roll 3 is pressed and supported in the horizontal direction in noncontact.
  • Beams 27 and 28 having large rigidity are disposed at the hydrostatic bearings 21 and 22 , and the rigid beams 27 and 28 are installed to hydrostatic bearing position setting apparatuses 31 and 32 fixed to the housings 15 and 17 .
  • the hydrostatic bearing position setting apparatuses 31 and 32 are provided with hydrostatic pressing force detecting apparatuses 41 and 42 such that a press support force of the hydrostatic bearings 21 and 22 can be detected.
  • a screw type is shown for the hydrostatic bearing position setting apparatuses 31 and 32 in FIG. 2, a cylinder type may be adopted. Further, the hydrostatic press force detecting apparatuses 41 and 42 may be means for directly detecting pressure other than load cells.
  • notation Ft designates a drive tangential force based on torque T of the intermediate roll 5 supporting the work roll 3 in the up and down direction
  • notation Tb designates an entry side tension exerted to the strip 1
  • notation Tf designates a delivery side tension exerted to the strip 1 .
  • FIG. 4A shows a model of a mode when horizontal bending caused in the work roll 3 by rolling is supported by using the first embodiment as an example and FIG. 4B illustrates a bending amount ⁇ caused in the work roll 3 at the occasion.
  • a distance between both end support portions is designated by notation L
  • a length Lb of the hydrostatic bearing is set to 0.83 L
  • FIG. 5 shows the axial bending ⁇ in three cases of the sheet width W of 0.83 L (in correspondence with a 0 , a), 0.67 L (in correspondence with b) and 0.5 L (in correspondence with c, c′).
  • FIG. 6 shows a calculation result of reaction Rc (in correspondence with load side) of the both end portion supporting points at that occasion in a ratio thereof to a value (a 0 ) in the case of both end simple support.
  • Curves (a), (b) and (c) shown in FIGS. 5 and 6 correspond to a state in which the both end portions of the work roll 3 are supported by the both ends support rolls 9 , 10 , 11 and 12 and the center portions thereof are supported by the hydrostatic bearings 21 and 23 . It is apparent that in any of them, the bending ⁇ is restrained to be small and the reaction of the both end support portions is as small as a negligible extent.
  • the support force exerted to the both end support portions by the both ends support rolls 10 and 12 on the reference side should be set so that the support force is equal to or larger than the minimum force by which slippage is not caused between the work roll 3 and the both ends support rolls 10 and 12 and is equal to or smaller than the strength allowance load of the both ends support rolls 10 and 12 on the reference side.
  • the press force exerted to the both end support portions by the both ends support rolls 9 and 11 on the pressing side may be set to a value as large as possible within the strength allowance load of the both ends support rolls 9 and 11 on the pressing side.
  • the actual setting and control is driven by, on the reference side, adjusting fluid pressure supplied to the both ends support roll position setting apparatuses 13 and 14 , the hydrostatic bearing position setting apparatuses 33 and 34 , and the hydrostatic bearing 23 and is driven by, on the pressing side, adjusting fluid pressure supplied to the both ends support roll pressing apparatuses 37 and 38 , the hydrostatic bearing position setting apparatuses 31 and 32 , and the hydrostatic bearing 21 .
  • the side that receives the load can be changed to both entry side and delivery side directions of the rolling pass direction depending on an offset amount of the work roll 3 , mentioned later, or other rolling conditions and therefore, it is necessary to determine the hydrostatic bearing to be used based on the rolling mill setting conditions at that occasion.
  • (c′) shows a case in which the calculation is carried out on condition that the length Lb of the hydrostatic bearing is the same as that of the sheet width W and in that case, the bending curve become smooth and the direction of the reaction at the both end support portions is stabilized without being reversed. Therefore, it is preferable in the hydrostatic bearings 21 and 23 to set an effective support length as long as the sheet width by changing the length in accordance with the sheet width W of the strip 2 .
  • a fluid pressure circuit 44 for supplying a fluid to a plurality of pockets 43 of the hydrostatic bearing 21 is constituted by separate paths in the width direction, the pockets 43 are selected by means of valves or the like in accordance with the sheet width W and supply of hydraulic pressure is distributed.
  • the present invention is similarly applicable also to a case in which there is a positional shift (offset) in the rolling pass direction between the work roll 3 and the intermediate roll 5 supporting the work roll 3 in the up and down direction. That is, when there is not the offset amount, the force S in the horizontal direction exerted to the work roll 3 is as follows.
  • FIG. 10 is a vertical sectional view of principal portions of strip rolling mill 46 according to a second embodiment of the present invention and FIG. 11 is a horizontal sectional view of principal portions of the strip rolling mill 46 .
  • a point of difference from the first embodiment resides in that according to the first embodiment, the barrel center portions of the work rolls 3 and 4 are supported in the horizontal direction directly by the hydrostatic bearings 21 , 22 , 23 and 24 , whereas according to the second embodiment, undriven idle rolls 47 , 48 , 49 and 50 are arranged between the work rolls 3 and 4 and the hydrostatic bearings 21 , 22 , 23 and 24 and the work rolls 3 and 4 are supported via the idle rolls 47 , 48 , 49 and 50 .
  • the work rolls 3 and 4 are sometimes ground and reused, and at that occasion, diameters of the work rolls 3 and 4 are changed.
  • the second embodiment is preferable in view of a drawback in practice.
  • FIG. 12 is a vertical sectional view of principal portions of a strip rolling mill 51 according to a third embodiment of the present invention and FIG. 13 is a horizontal sectional view of principal portions of the strip roll mill 51 .
  • the second embodiment is constructed by the constitution in which the both ends support roll position setting apparatuses 13 and 14 on the reference side and the both ends support roll pressing apparatuses 37 and 38 on the pressing side are respectively installed and fixed to the housings 15 , 16 , 17 and 18
  • the both ends support roll position setting apparatuses 13 and 14 on the reference side are installed to the reference side rigid beam 29 and the both ends support roll position pressing apparatuses 37 and 38 on the pressing side are installed on the pressing side rigid beam 27 to thereby integrally constitute respectively total support apparatuses 52 and 54 .
  • the hydrostatic support force detecting apparatuses 35 and 36 detect a summed-up force of a total (total support force) including the both end support force and accordingly, when only the hydrostatic support force exerted to the hydrostatic bearing 23 is detected, it is necessary to calculate the hydrostatic support force by subtracting the both ends support force from the total support force.
  • the horizontal direction bending of the work roll caused in the rolling transient condition such as when starting the rolling operation or when finishing the rolling operation can effectively be shared by means of the both ends support rolls and the hydrostatic bearings to thereby surely support the work roll.
  • the work roll can always be supported pertinently by the hydrostatic bearings via contact of the idle rolls.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Reduction Rolling/Reduction Stand/Operation Of Reduction Machine (AREA)
  • Rolls And Other Rotary Bodies (AREA)
  • Magnetic Bearings And Hydrostatic Bearings (AREA)
  • Battery Electrode And Active Subsutance (AREA)
US09/790,648 2000-02-23 2001-02-23 Strip rolling mill and strip rolling method Abandoned US20010018840A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2000-46118 2000-02-23
JP2000046118A JP2001232402A (ja) 2000-02-23 2000-02-23 板材圧延機および板材圧延方法

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US20010018840A1 true US20010018840A1 (en) 2001-09-06

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US09/790,648 Abandoned US20010018840A1 (en) 2000-02-23 2001-02-23 Strip rolling mill and strip rolling method

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US (1) US20010018840A1 (ko)
JP (1) JP2001232402A (ko)
KR (1) KR20010085456A (ko)
CN (1) CN1310061A (ko)
DE (1) DE10107679A1 (ko)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005123290A1 (en) * 2004-06-17 2005-12-29 Luvata Oy Compact rolling mill and a method of producing a thin strip
US11872612B2 (en) 2019-04-04 2024-01-16 Sendzimir Japan, Ltd. Multistage rolling mill

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5669403B2 (ja) * 2009-01-20 2015-02-12 株式会社神戸製鋼所 ロールオフセット機構を備えたクラスタ型多段圧延機
BR112013015742B1 (pt) * 2010-12-02 2020-12-29 Primetals Technologies France SAS equipamento de desmontagem adequado para troca de cilindros e blocos de um suporte de rolos destinado à laminação de uma tira de metal, suporte de rolos e método para troca de cilindros e blocos de um suporte de rolos
CN102877248B (zh) * 2012-09-13 2015-02-18 梁少奇 压力辅助防止中边压力不均匀的纺织染压辊
DE102021205156A1 (de) * 2021-05-20 2022-11-24 Sms Group Gmbh Kassette für zumindest eine Arbeitswalze in einem Walzgerüst

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005123290A1 (en) * 2004-06-17 2005-12-29 Luvata Oy Compact rolling mill and a method of producing a thin strip
US7131307B2 (en) 2004-06-17 2006-11-07 Outokumpu Oyj Compact rolling mill and a method of producing a thin strip
US11872612B2 (en) 2019-04-04 2024-01-16 Sendzimir Japan, Ltd. Multistage rolling mill

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Publication number Publication date
JP2001232402A (ja) 2001-08-28
CN1310061A (zh) 2001-08-29
KR20010085456A (ko) 2001-09-07
DE10107679A1 (de) 2001-09-13

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Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:NIHEI, MISTUO;YASUDA, KENICHI;HIRAMA, YUKIO;AND OTHERS;REEL/FRAME:011564/0793;SIGNING DATES FROM 20010130 TO 20010131

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