EP1022068A1 - Lochwalzwerk - Google Patents

Lochwalzwerk Download PDF

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Publication number
EP1022068A1
EP1022068A1 EP98947859A EP98947859A EP1022068A1 EP 1022068 A1 EP1022068 A1 EP 1022068A1 EP 98947859 A EP98947859 A EP 98947859A EP 98947859 A EP98947859 A EP 98947859A EP 1022068 A1 EP1022068 A1 EP 1022068A1
Authority
EP
European Patent Office
Prior art keywords
disk
frame
frames
chock
piercing
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Withdrawn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
EP98947859A
Other languages
English (en)
French (fr)
Other versions
EP1022068A4 (de
Inventor
Hisao Sumitomo Metal Industries Ltd. GOTO
Yoichi Sumitomo Metal Industries Ltd. YOKOI
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
Application filed by Sumitomo Metal Industries Ltd filed Critical Sumitomo Metal Industries Ltd
Publication of EP1022068A1 publication Critical patent/EP1022068A1/de
Publication of EP1022068A4 publication Critical patent/EP1022068A4/de
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B19/00—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work
    • B21B19/02—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work the axes of the rollers being arranged essentially diagonally to the axis of the work, e.g. "cross" tube-rolling ; Diescher mills, Stiefel disc piercers or Stiefel rotary piercers
    • B21B19/04—Rolling basic material of solid, i.e. non-hollow, structure; Piercing, e.g. rotary piercing mills
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B31/00—Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
    • B21B31/08—Interchanging rolls, roll mountings, or stand frames, e.g. using C-hooks; Replacing roll chocks on roll shafts

Definitions

  • the present invention relates to a piercing mill for use with a seamless steel tube and, more particularly, to a piercing mill which enables thin-wall piercing without impairing the ease of work for adjusting position of disk rollers.
  • the Mannesmann tube-making process is widely employed.
  • a round billet heated to a high temperature is fed as a material to be rolled into a piercing mill (a so-called "piercer"), which pierces the axial center portion of the round billet to obtain a hollow shell.
  • the thus-obtained hollow shell is fed, directly or as needed after undergoing an expansion or wall-thinning process in an elongator having the same structure as that of the piercing mill, into a subsequent elongating mill such as a plug mill, a mandrel mill, or the like so as to be elongated.
  • the thus-elongated tube undergoes a finishing process provided by a stretch reducer for shape correction, a reeler for polishing, and a sizer for sizing, thereby becoming a seamless steel tube product.
  • the piercing mill is comprised of a pair of piercing rollers disposed in a vertical direction with respect to a pass line of a material to be rolled, and a pair of disk rollers disposed in a direction perpendicular to the direction of layout of the piercing rollers.
  • the piercing mill is arranged so as to pierce and roll the material while supporting and rotating it by use of the piercing rollers and the disk rollers.
  • the piercing rollers and the disk rollers are integrally retained and fixedly positioned with respect to each other within a mill housing during at least the rolling operation.
  • the piercing mill processes the material while pressing the piercing rollers down on the material remained at a high temperature, and therefore working surfaces of the piercing rollers are damaged with a lapse of roll time.
  • the disk rollers are also abraded when they come into contact with the material.
  • the piercing rollers and the disk rollers must be periodically exchanged.
  • the disk rollers must be exchanged by lifting them one at a time by use of an overhead traveling crane while the mill housing is in an open state. Use of such an overhead traveling crane in the exchange the pair of disk rollers consumes much time, inevitably resulting in a reduction in the availability of the piercing mill.
  • a bulge in the outer circumference increases as the degree of draft in the wall thickness of the hollow shell increases, in turn making the hollow shell susceptible to guide flaws.
  • FIG. 1 is a schematic representation of the anomalous shape of a thin-wall hollow shell formed when the hollow shell is rolled by piercing rollers through use of disk rollers.
  • material 1 to be rolled is helically traveling in a direction perpendicular to the plane of the drawing while being pierced by a plug 3 and rolled by piercing rollers 2, and disk rollers 4.
  • the bulge in the circumference of the material 1 becomes large as a result of a decrease in the degree of draft, the material 1 is partially drawn into the clearance between the edge of a material-receiving side of each disk roller 4 and the outgoing side of the corresponding piercing roller 2, thereby generating guide flaws in the outer surface of the material.
  • the disk rollers 4 are arranged so as to cross each other at a predetermined skew angle ⁇ (alpha) with respect to a pass line X-X along which the material travels while being rolled, such that the edges of the disk rollers 4 become parallel to outgoing sides of the piercing rollers 2 with a small clearance between them. In this case, if the support rigidity of the disk rollers 4 is insufficient, the disk rollers 4 rotate in an eccentric manner, thereby promoting generation of guide flaws.
  • the conventionally-proposed piercing mill is likely to generate flaws in the surface of a material to be rolled because of low support rigidity of disk rollers. Further, in the case where the disk rollers are arranged at a skew angle ⁇ , eccentric rotations of the disk rollers cannot be prevented, thereby promoting generation of the guide flaws.
  • the object of the present invention is to solve the drawbacks in the conventional piercing mill and to provide a piercing mill which enables flexible manufacture of a variety of differently-sized seamless steel tubes in small quantities by improving the ease of work such as setting of the skew angle ⁇ of the disk rollers, while ensuring sufficient support rigidity of the disk rollers and expanding the range of thin-wall tube rolling, to thereby improve the performance of the piercing mill.
  • the gist of the present invention resides in a piercing mill for use in manufacturing seamless steel tubes as defined by the following (1) through (4). Part number used therein are described in FIG. 4 and 5, which will be described later.
  • a piercing mill of the present invention is chiefly characterized by a pair of disk frames which are attached to the respective lateral sides of the mill housing and which can be opened sideward in a pivoting way; and a pair of sliding frames which are vertically arranged within each of the disk frames so as to be slidable and to hold the disk roller integrally formed with a shaft; wherein a skew angle of each of the disk roller is set by sliding the corresponding sliding frames in opposite directions.
  • the disk rollers can be exchanged without use of an overhead traveling crane.
  • the piercing mill comprises upper and lower chock frames which are provided at either end of the shaft of the disk roller and which support and incorporate chocks while permitting pivoting motion; and upper and lower opening control frames which are respectively attached to the upper and lower sliding frames and control the respective positions of the chock frames.
  • the disk roller integrally formed with the shaft can be supported at both of its ends by respectively fitting the chock frames into the opening control frames.
  • the clearance between the exit-side rollers and the disk rollers can be minimized, so that the range of thin-wall tube rolling can be expanded. Further, since sufficient support rigidity can be secured, it is possible to prevent the generation of surface flaws in the material which would otherwise result from eccentric rotation of the disk rollers when they come into contact with the material during piercing and rolling operation. Further, an example of the scheme for supporting the chock while permitting pivoting motion is a pin support.
  • the piercing mill further comprises a screw-down mechanism provided on each of the upper and lower sliding frames and a balancing device provided on the upper sliding frame or on each of the upper sliding frame and the upper opening control frame.
  • the opening of the disk roller is adjusted by the screw-down mechanism, and the height of the disk roller is adjusted by the balancing device.
  • the piercing mill further comprises a rotary shaft for supporting the shaft of the disk frame, clamping means provided on the disk frame, and a clamping device disposed on the mill housing.
  • the disk frame is fixedly supported in a heightwise direction thereof by means of the rotary shaft and the clamping means, as well as in the direction of pivotal movement of the disk frame by the clamping device when it is closed and fixed to the mill housing.
  • the piercing mill of the present invention it become possible to secure the support rigidity of the disk rollers and enable the production of tubes having a thinner wall, to thereby improve the performance of the piercing mill, while improving the ease of work for adjusting the position of disk rollers. Further, as described above, it is possible to achieve a reduction in the time required to exchange the disk rollers, as well as to save significantly labor in the operations themselves.
  • FIG. 3 through 8 An example of a specific structure of the piercing mill of the present invention is shown in FIG. 3 through 8, with reference to which the effects will be described in detail. Throughout the drawings, elements common to the drawings are assigned the same reference numerals.
  • FIG. 3 is a view showing an example of the structure of a mill housing of a piercing mill according to the present invention.
  • a mill housing 5 which constitutes the main body of the piercing mill, the surfaces in a direction perpendicular to a pass line X-X are opened.
  • a pair of piercing rollers 2 which are disposed so as to be opposite to each other with respect to the pass line X-X, and a pair of disk rollers 4 which are disposed so as to be opposite to each other and orthogonal to the piercing rollers 2.
  • a pair of disk frames 6 are supported by rotary shafts 7 on the respective lateral surfaces of the mill housing 5 and can be opened sideward in a pivoting manner.
  • a disk roller 4 integrally formed with a shaft is supported on the internal surface of each disk frame 6.
  • FIG. 4 is a perspective view showing the overall structure by which a disk frame is supported when the disk frame is pivoted.
  • the disk frame 6 is supported by the rotary shaft 7 and is pivoted by the action of an unillustrated pivot cylinder. Exchange of the disk roller is performed in a state in which the disk frame 6 is swung.
  • upper and lower sliding frames 8 and upper and lower opening control frames 10 attached thereto are provided in order to vertically support the disk roller 4.
  • FIG. 5 is a perspective view illustrating a main structure of the disk frame supporting the disk roller integrally formed with the shaft.
  • the sliding frame pair 8 consisting of the pair of an upper sliding frame 8a and a lower sliding frame 8b is provided within the disk frame 6.
  • the upper and lower sliding frames 8a and 8b can slide in the direction indicated by arrow by the operation of a hydraulic cylinder 9 and a screw-down jack 9a (a hydraulic cylinder for use with the upper sliding frame 8a is not shown in the drawing).
  • the upper opening control frame 10a is provided at the front end of the center of the upper sliding frame 8a
  • the lower opening control frame 10a is provided at the front end of the center of the lower sliding frame 8b.
  • the disk roller 4 is integrally formed with a shaft 4s.
  • an upper chock 13 is fitted to an upper part of the shaft 4s of the disk roller 4, and this upper chock 13 is connected to a chock frame 11 via pin support. Since the chock 13 is retained by and incorporated in the upper chock frame 11 through support by a pin 13p, it can be pivoted in the direction of a skew line with skewing operations, which will be described later.
  • a lower chock frame 12 which incorporates and supports the chock 13 via a pin, as is the case with the upper chock frame 11, is fitted around a lower part of the shaft 4s.
  • a screw-down screw support groove 11c for receiving a screw-down screw of a balancing device, which will be described later, is formed in the upper chock frame 11, and the upper chock frame 11 is fitted into the upper opening control frame 10a provided in the upper sliding frame 8a.
  • the lower chock frame 12 is fitted into the lower opening control frame 10b provided in the lower sliding frame 8b.
  • the disk roller 4 are vertically supported through its the opposite ends such that the upper chock 13 and the lower chock 13 are aligned vertically.
  • the chocks 13 incorporated in the respective chock frames 11 and 12 are tilted around the pin 13b as a result of sliding of the upper and lower sliding frames 8a and 8b in opposite directions, setting the skew angle ⁇ of the disk roller 4 to a predetermined angle.
  • FIG. 6 is a schematic illustration of an operation required to set the skew angle ⁇ of the disk roller.
  • the upper chock frame 11 is fitted into the upper opening control frame 10a
  • the lower chock frame 12 is fitted into the lower opening control frame 10b, so that the disk roller 4 is at both of its ends supported and is positioned in axis Y1-Y1 perpendicular to the pass line X-X.
  • the chock frames 11 and 12 cause parallel movement.
  • the chocks 13 having the pins 13p supported by the chock frames 11 and 12 are tilted about the pins 13p along Y2-Y2 axis, so that the disk rollers 4 is located on Y2-Y2 axis.
  • the disk roller 4 is tilted at a predetermined skew angle ⁇ with respect to the pass line X-X.
  • the position of the disk roller 4; i.e., its height and opening is adjusted by the balancing device provided on the upper sliding frame, as well as by a screw-down mechanism provided on the sliding frame pair 8.
  • the relationship between the arrangement of the disk rollers and the height and opening adjustment is shown in FIG. 7, which will be described next.
  • the sliding of the disk roller in the front/back direction is performed by the operation of the hydraulic cylinder and the screw-down jack provided on each of the upper and lower sliding frames.
  • FIG. 7 is a vertical cross-sectional view showing an example of the structure of the pair of disk rollers disposed so as to be opposite to each other within a mill housing.
  • the material 1 to be rolled is helically traveling in a direction perpendicular to the plane of the drawing, and a pair of disk rollers 4, 4' are disposed so as to support this material 1.
  • a thrusting force F1 and a rolling force F2 act on the disk rollers 4, 4'.
  • the pair of disk rollers 4, 4' are identical to each other regarding construction exclusive of the degree of exertion of the thrusting force F1. Therefore, an explanation will be hereinbelow given to solely the construction and operation of the disk roller 4 of the disk roller pair provided on the lift side of the drawing.
  • the disk roller 4 is at both of its ends supported reliably, thereby providing sufficient support rigidity.
  • the balancing device 14 for controlling the height of the disk roller 4 is comprised of a screw-down (screw-up) screw 15 and a pull-back rod 16.
  • the screw-down screw 15 is disposed on the upper opening control frame 10a, and the pull-back rod 16 is disposed on the upper sliding frame 8a.
  • the screw-down screw 15 is disposed on the upper opening control frame 10a in FIG. 7, it may be provided on the upper sliding frame 8a.
  • the height of the disk roller 4 is set according to the amount of movement of the screw-down screw 15. That is, the screw-down screw 15 is inserted into the screw-down screw support groove 11c provided in the upper chock frame 11 and adapted to adjust the height of the disk roller 4. At this time, a pre-load is exerted on the disk roller 4. More specifically, as indicated by an arrow in the drawing, the pull-back rod 16 is inserted into the support groove 13c formed in the upper chock 13 and provides upward pressure in the direction opposite to the direction of screw-down action of the screw-down screw 15. This operation is called a "backlash elimination.” Since the height of the disk roller 4 is controlled after the backlash has been absorbed, the accuracy of adjustment of the disk roller 4 is improved.
  • the disk roller 4' provided on the right side of FIG. 7 receives the thrusting force F1 from the material 1 in the opposite direction, and therefore the pre-load is exerted on the disk roller 4' in the direction opposite to the direction in which the disk roller 4 receives the pre-load.
  • the disk rollers 4, 4' on both sides of mill housing 5 are identical to each other.
  • Screw-down mechanisms 17 for controlling the opening of the disk roller 4 are each made up of the screw-down (screw-up) screw 15 and a pull-back rod (not shown), as is the case with the balancing device 14.
  • the screw-down mechanisms 17 are provided to the respective upper and lower sliding frames 8a and 8b.
  • the opening on the upper or lower side of the disk roller 4 is independently controlled according to the movement amount of the corresponding screw-down screw 15.
  • the positions of the disk roller 4 are controlled while the backlash of the screw-down mechanism 17 by virtue of the pulling back action of the pull-back rod, and therefore the accuracy of adjustment of the disk roller can be considerably improved.
  • the disk frames are closed and fixedly attached to the mill housing during the piercing and rolling operation.
  • the disk frames 6 are each fixedly maintained in a heightwise direction thereof by a combination of the rotary shaft 7 pivotally supporting the disk frame 6 and clamping means 18 provided on the disk frame 6.
  • the disk frames 6 are fixed in a pivoting direction thereof by a clamping device 19 disposed on the mill housing 5 at a disk frame closure position.
  • FIG. 8 is a schematic representation showing an example of the structure of a clamping device disposed at a disk frame closure position in order to fix the disk frame to the mill housing.
  • a clamping device 19 is made up of a hydraulic cylinder 19a, a clamp lever 19b, a clamp 19c, and a clamp block 19d.
  • the disk frame 6 is fixed in its pivoting direction by the clamp lever 19b and the clamp 19c as a result of actuation of the hydraulic cylinder 19a via the clamp block 19d attached to the disk frames.
  • the piercing mill of the present invention it become possible to improve the ease of work for positional adjustment required upon exchange of disk rollers without use of an overhead traveling crane, while enabling easy and reliable setting of a skew angle of the disk roller, whereby production of tubes having thinner wall is enabled.
  • the piercing mill is arranged so as to be able to support both ends of a shaft integrally formed with the disk roller, which allows ensure of sufficient support rigidity. As a result, the disk rollers are prevented from rotating in an eccentric manner during the piercing and rolling operations, in turn preventing generation of surface flaws in the material to be rolled.
  • the piercing mill of the present invention is equipped with superior position adjustment and clamping mechanisms, the ease of work for position adjustment and setting accuracy are maintained, and the ease of the work for exchanging disk rollers can be improved without impairment of its function.
  • the piercing mill of the present invention can be widely utilized in the field of seamless tube production so as to improve the production efficiency.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Metal Rolling (AREA)
  • Crushing And Grinding (AREA)
EP98947859A 1997-10-14 1998-10-14 Lochwalzwerk Withdrawn EP1022068A4 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP28002097 1997-10-14
JP28002097 1997-10-14
PCT/JP1998/004630 WO1999019093A1 (fr) 1997-10-14 1998-10-14 Laminoir perceur

Publications (2)

Publication Number Publication Date
EP1022068A1 true EP1022068A1 (de) 2000-07-26
EP1022068A4 EP1022068A4 (de) 2002-01-16

Family

ID=17619189

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98947859A Withdrawn EP1022068A4 (de) 1997-10-14 1998-10-14 Lochwalzwerk

Country Status (3)

Country Link
EP (1) EP1022068A4 (de)
JP (1) JP3239896B2 (de)
WO (1) WO1999019093A1 (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104098257A (zh) * 2013-04-03 2014-10-15 颜良德 螺旋明管弯脚机
WO2016128923A1 (en) * 2015-02-11 2016-08-18 Danieli & C. Officine Meccaniche S.P.A. Cross-rolling rolling stand for seamless pipes, with interchangeable lateral guide device
CN111842742A (zh) * 2020-08-26 2020-10-30 太原科技大学 一种锥齿轮传动的单环辊旋轧机构
CN112024607A (zh) * 2020-08-26 2020-12-04 太原科技大学 一种锥齿轮传动的双环辊旋轧机构

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100496780C (zh) * 2006-12-29 2009-06-10 太原重工股份有限公司 一种大型卧式穿孔机轧辊箱碾轧角调整装置
CN107876566B (zh) * 2017-12-14 2023-07-04 天津腾飞钢管有限公司 一种无缝钢管定位调节装置
CN111804855B (zh) * 2020-08-26 2022-08-02 太原科技大学 一种三自由度旋轧机

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4488419A (en) * 1981-08-19 1984-12-18 Kocks Technik Gmbh & Co. Skew rolling mill for tubes
JPS6364248A (ja) * 1986-09-05 1988-03-22 Hitachi Ltd カラ−受像管
US5479805A (en) * 1993-03-15 1996-01-02 Mannesmann Aktiengesellschaft Two-high cross rolling mill with guide disks

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS591008A (ja) * 1982-06-25 1984-01-06 Ishikawajima Harima Heavy Ind Co Ltd ピアサ−のデイスクガイド交換装置
JPS6390306A (ja) * 1986-10-02 1988-04-21 Kawasaki Steel Corp 継目無管の傾斜式圧延方法および装置
JP2815749B2 (ja) * 1992-01-23 1998-10-27 住友重機械工業株式会社 竪型傾斜穿孔機
JP2558263Y2 (ja) * 1993-06-29 1997-12-24 住友重機械工業株式会社 交叉穿孔機用ディスクロ−ルの調整装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4488419A (en) * 1981-08-19 1984-12-18 Kocks Technik Gmbh & Co. Skew rolling mill for tubes
JPS6364248A (ja) * 1986-09-05 1988-03-22 Hitachi Ltd カラ−受像管
US5479805A (en) * 1993-03-15 1996-01-02 Mannesmann Aktiengesellschaft Two-high cross rolling mill with guide disks

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 012, no. 287 (E-643), 5 August 1988 (1988-08-05) & JP 63 064248 A (HITACHI LTD), 22 March 1988 (1988-03-22) *
See also references of WO9919093A1 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104098257A (zh) * 2013-04-03 2014-10-15 颜良德 螺旋明管弯脚机
CN104098257B (zh) * 2013-04-03 2016-08-03 颜良德 螺旋明管弯脚机
WO2016128923A1 (en) * 2015-02-11 2016-08-18 Danieli & C. Officine Meccaniche S.P.A. Cross-rolling rolling stand for seamless pipes, with interchangeable lateral guide device
CN107206441A (zh) * 2015-02-11 2017-09-26 丹尼尔和科菲森梅克尼齐有限公司 具有可更换的侧向引导设备的用于无缝管的交叉轧制式轧制机架
CN111842742A (zh) * 2020-08-26 2020-10-30 太原科技大学 一种锥齿轮传动的单环辊旋轧机构
CN112024607A (zh) * 2020-08-26 2020-12-04 太原科技大学 一种锥齿轮传动的双环辊旋轧机构

Also Published As

Publication number Publication date
EP1022068A4 (de) 2002-01-16
JP3239896B2 (ja) 2001-12-17
WO1999019093A1 (fr) 1999-04-22

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