EP0304490A1 - Verfahren zum entzundern von flachstahl - Google Patents

Verfahren zum entzundern von flachstahl Download PDF

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Publication number
EP0304490A1
EP0304490A1 EP19880901482 EP88901482A EP0304490A1 EP 0304490 A1 EP0304490 A1 EP 0304490A1 EP 19880901482 EP19880901482 EP 19880901482 EP 88901482 A EP88901482 A EP 88901482A EP 0304490 A1 EP0304490 A1 EP 0304490A1
Authority
EP
European Patent Office
Prior art keywords
descaling
steel strip
powder
zone
steel
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Withdrawn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
EP19880901482
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0304490A4 (de
Inventor
Jury Viktorovich Lipukhin
Leonid Ivanovich Danilov
Eduard Alexandrovich Garber
Anatoly Nikolaevich Subbotin
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.)
CHEREPOVETSKY FILIAL VOLOGODSKOGO POLITEKHNICHESKO
Original Assignee
CHEREPOVETS VOLOG POLITEKH I
CHEREPOVETSKY FILIAL VOLOGODSKOGO POLITEKHNICHESKOGO INSTITUTA
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 CHEREPOVETS VOLOG POLITEKH I, CHEREPOVETSKY FILIAL VOLOGODSKOGO POLITEKHNICHESKOGO INSTITUTA filed Critical CHEREPOVETS VOLOG POLITEKH I
Publication of EP0304490A4 publication Critical patent/EP0304490A4/de
Publication of EP0304490A1 publication Critical patent/EP0304490A1/de
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B31/00—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor
    • B24B31/10—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor involving other means for tumbling of work
    • B24B31/112—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor involving other means for tumbling of work using magnetically consolidated grinding powder, moved relatively to the workpiece under the influence of pressure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/04—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for de-scaling, e.g. by brushing
    • B21B45/06—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for de-scaling, e.g. by brushing of strip material

Definitions

  • the present invention relates to the metallurgical industry and relates to a method for descaling flat steel.
  • a method for descaling flat steel is known (SU, A, 902378), in which the strip runs vertically from bottom to top through a working chamber filled with a ferromagnetic, abrasive powder and a means for pressing the powder onto the strip which is in the form of blades which are attached to shafts which can be pivoted about 30 to 40 ° about axes.
  • the blades press the powder onto the moving belt from both sides, while magnets attached behind the shafts compress the powder, the descending belt being descaled on both sides.
  • the disadvantage of this method is that the vertical position of the belt during the treatment requires a large height of the working chamber, which means that the height of the workshop and the crane tracks has to be increased, which necessitates additional investment costs.
  • the working chamber is very metal-consuming, an expensive, non-magnetic steel is required in large quantities for its manufacture and finally, to deflect the belt from the horizontal position into the vertical and vice versa, no less than three deflection rollers with a diameter of 1.1 to 1.2 m, which additionally requires metal for the production of the rolls themselves and energy for bending the band when deflecting over the rolls.
  • a method for descaling flat steel is known (SU, A, 887048), in which a powder and the flat steel to be descaled are pressed against one another, the steel strip running flat in a horizontal drawer through slots in the side walls of a tubular working chamber and the powder laterally fed into the chamber, pushed through the tube along the axis by means of a piston and removed at the other end by a valve.
  • the present invention has for its object to provide a method for descaling flat steel, in which the descaling of the flat steel is carried out by the pressure which is generated by the moving steel strip itself, without a container for .Receiving the ferromagnetic powder use, which can simplify the implementation of the process, reduce the length of the system and improve the quality of descaling.
  • This object is achieved in that, in a method for descaling flat steel, which involves pulling the steel strip flat in a horizontal position through the descaling zone, which contains an abrasive, ferromagnetic powder, the mutual pressing of the powder and the surface of the steel strip to be descaled during this Locomotion, the feeding of the powder into the descaling zone and its removal from this zone holds, according to the invention, the flat steel is first drawn in one direction and then in the opposite direction through the descaling zone, forming an upper and lower strand and the descaling zone being between these strands.
  • the arrangement of the descaling zone between two strands of the steel strip, namely an upper and a lower one, which are pulled through first in one and then in the opposite direction, makes it possible to dispense with a special container, i.e. to a working chamber, and as a result of the simplification of the process, a substantial reduction in the investment and operating costs for operation and repair, and also a shortening of the production line.
  • the approximation of the side edges of the upper and lower strands of the steel strip in the descaling zone by bending the strip in transverse planes enables the spillage of the powder from the descaling zone to be reduced (or completely eliminated) over the side edges of the strip and thus creates conditions for maintenance a constant pressure of the powder on the belt in the scaling zone, which is necessary to achieve constant force relationships during descaling along the length of the belt.
  • the powder is pressed more strongly on the side edges of the strip than in the middle, which makes descaling more effective at the sections of the steel strip adjacent to the side edges, where, as is known, the scale is stronger and adheres more strongly to the base metal than in Middle of the band. In this way, the approximation of the side edges of opposite strands of the steel strip improves the quality of descaling both on the length and on the width of the flat steel as a whole.
  • the process according to the invention for descaling flat steel consists in first pulling the steel strip flat in a horizontal position in one direction and thus forming the lower strand of the steel strip, then bending it upwards by 180 °, pulling it in the opposite direction and thus the upper strand of the steel strip that runs over the lower strand.
  • a ferromagnetic, abrasive Powder fed and on the other side, for example on the right, this powder is removed from this room.
  • the lower strand of the strip is rotated by 180 about its longitudinal axis as it emerges from the descaling zone, and at the point of this turn the used out of the descaling zone from the lower strand of the strip is used Powder automatically falls off the belt and enters a circulation and separation system for the powder.
  • the side edges of the upper and lower strand of the steel strip in the descaling zone are additionally brought closer to one another by bending the steel strip in transverse planes.
  • the front and rear ends of the steel strip can be butt-welded.
  • the flat steel is drawn as an infinite strip through the descaling zone formed by the two opposite strands of the strip, i.e. the strip passes through this zone several times until it is completely descaled.
  • Butt welding the front and rear ends of the flat steel and transporting it as an infinite strip through the descaling zone enables only one descaling zone formed by the upper and lower strands of the steel strip to completely descaling the flat steel. This is useful in the case when the descaling section of the production line does not require high performance. In this case, it is not justified to set up three to four descaling zones on the production line with intermediate stations for pulling the strip, as this takes up additional costs and production space. It is much cheaper to let the steel strip run through the descaling zone as an infinite strip until it is completely descaled no more than (experience has shown that no more than three to four passes are required for this).
  • the butt welding of the front and rear ends of the flat steel provides the spatial coverage of these ends so that the front end of the steel strip can be returned to the descaling zone through which the upper and lower strands of the strip run in opposite directions.
  • FIGS. 1 and 2 The process according to the invention for descaling flat steel is realized with a production line which is shown in FIGS. 1 and 2, where the steel strip 1 rests with its upper 2 and its lower strand 3 on pressure rollers 4 which approach each other and the width of the slot 5 between the upper 2 and lower 3 strand of the steel strip 1 on the left (naoh Fig. 1) of the descaling zone filled with a powder 6 can change.
  • Magnetic conductors 7 of electromagnets with coils 8 are attached on the outside of the descaling zone above or below the steel strip 1 with opposite poles N and S.
  • pressure rollers 9 which, like the rollers 4, approach each other and can change the width of the slot 10 between the upper 2 and the lower 3 strand of the steel strip 1.
  • the lower strand 3 of the Steel strip 1 rotated by 180 ° about its longitudinal axis.
  • a deflection roller 12 which deflects the steel strip 1 and thereby transfers the lower strand 3 to the upper 2.
  • the steel strip 1 then runs with its upper strand 2 through a tensioning system 13 for pulling the lower strand 3 of the steel strip 1 through the descaling zone filled with powder 6, which is enclosed between the magnetic conductors 7 and the coils 8.
  • the upper strand 2 of the steel strip 1 forms the upper limit of the descaling zone filled with powder 6 with the aid of the upper pressure rollers 4 and 9 and the magnetic conductor 7.
  • a tensioning system 14 serves to pull the upper strand 2 of the steel strip 1 through the descaling zone.
  • the front end 15 of the flat steel 1 runs further to the left on the production line, which can still contain two or three descaling zones (not shown in the figures).
  • the front end 15 is guided via a deflection roller 16 to a deflection roller 17 through a device 18 for processing the ends, which has a storage for a sole, a pair of scissors for trimming the ends, a resistance press butt welding machine for connecting the front End 15 of the standard strip 1 with its rear end 19 and a deburring machine for compensating for the thickness of the steel strip at the welding point of the ends contains (the machines of the system 18 are conditionally not shown in the figure).
  • a guide funnel 20 a vibration separator 21, a conveyor 22, an elevator (for example a bucket elevator) 23 and a feed conveyor 24.
  • a vibration separator 21 a conveyor 22
  • an elevator (for example a bucket elevator) 23 a feed conveyor 24.
  • non-metallic brushes 25 are provided which have a drive for the rotary movement (not shown in the figure).
  • rollers 28 are provided, the axes of which are inclined at an acute angle to the horizontal plane.
  • the axes of the rollers 28 are on the part of each strand of the steel strip 1 in uniform block with the associated M Ag netleitern 7 are connected such that the upper and lower magnetic conductor 7 with its coils 8 and rollers 28 themselves can approach apart from each other or one another, and form the descaling zone of the flat steel 1 filled with the powder 6.
  • FIG. 1 The direction of the circulation of the powder and the scale is indicated in FIG. 1 by arrows (arrow A - powder; arrow B - mixture of powder with scale, arrow C - scale).
  • the descaling of flat steel by the method according to the invention is carried out as follows.
  • the steel strip 1 is guided with the front end 15 first past the deflection roller 17, above the lower pressure roller 4, the lower magnetic conductor 7 and the lower pressure roller 9.
  • the upper and lower pressure rollers 4, 9 and the magnetic conductor 7 are moved up or down to the maximum distance from one another in order to simplify the insertion and the forward movement of the steel strip 1.
  • the front end 15 of the steel belt 1 is guided further to the left onto the production line. If the flat steel is to be descaled as an endless strip, the front end 15 is guided around the deflection roller 16 and further introduced into the end processing unit 18, where it is butt-welded to the rear end 19 of the steel strip 1, which previously stored the Belt sling and the deburring machine has happened, the parts of the system 18. Then the weld is deburred. This completes the introduction and preparation of the steel strip for operation.
  • the distance between the upper and lower magnetic conductors 7 and between the upper and lower rollers 28 is reduced and the slots 5 and 10 between the upper and lower rollers 4 and 9 are adjusted to such a width that the amount of the descaling zone powder 6 discharged from the lower strand 3 of the steel strip 1 onto the section 11 is equal to the amount of the powder 6 fed into the descaling zone between the rollers 4 is.
  • the descaling zone which is enclosed between the upper 2 and lower 3 strands, which are pressed against the powder by the rollers 4 , 9 and 28 and which are surrounded by magnetic conductors 7, of the steel strip 1 is fully formed and ready for operation Descaling the flat steel 1.
  • the drive for the rotary movement of the brushes 25 is switched on, they are brought up to the steel strip 1 and the coils of the electromagnets 8 are fed.
  • Magnetic fluxes arise between the poles N and S of the magnetic conductor 7, which reduce the pourability of the powder 6 and improve its abrasive properties.
  • the surface of the steel strip 1 facing the powder 6 is descaled. Since the steel strip 1 is rotated on the section 11 by 180 ° about its longitudinal axis, it is descaled on both sides.
  • the pressing force of the powder 6 on the steel strip 1, which is necessary to destroy the scale, is generated by the rollers 4, 9 and 28, which in turn are pressed against the steel strip 1 by pressing mechanisms (these mechanisms are not shown in the figure to a limited extent) ).
  • the tensioning devices 13 and 14 generate the forces necessary for pulling through the steel strip 1 and overcoming the resistance opposed by the powder 6 to the movement of the strip.
  • the powder 6 mixed with scale reaches during descaling through the slot 10 between the rollers 9 on the section 11 and falls due to the rotation of the steel belt 1 by 180 0 on this section independently through the funnel 20 onto the vibration separator 21.
  • the remnants of the Powders 6 are removed with the aid of the brushes 25, and this ensures that no particles of the powder 6 get between the deflection roller 12 and the steel strip 1, where they can damage the surface of the steel strip 1.
  • the mixture consisting of the powder 6 and scale is separated on the vibration separator 21: the scale is separated from the mixture by a sieve of the vibration separator 21 and sucked off in arrow direction "C", while the powder 6 cleaned from the scale on the conveyor 22 in the arrow direction "A" enters the receiving funnel of the elevator 23, which brings the powder upwards and empties it onto the belt of the feeder 29, from where it comes back to the lower strand 3 of the steel belt 1 for repeated use.
  • the strand 3 is bent like a gutter in the transverse plane, e.g. with the aid of rollers which are designed similarly to the rollers 28 (these rollers are conditionally not shown in FIGS. 1, 2).
  • the method according to the invention makes it easier to carry out the descaling process, to improve the quality of the descaling process and to reduce the investment and the length of the production line, while dispensing with such metal-consuming and complex assemblies as the housing of one Working chamber, a feed bunker, a valve mechanism for discharging the powder and a sciileuse with an electromagnet the cost of manufacturing the system can be significantly reduced.
  • the invention can be most successfully used in sheet metal rolling mills.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
  • Cleaning In General (AREA)
EP19880901482 1987-01-21 1988-01-15 Verfahren zum entzundern von flachstahl Withdrawn EP0304490A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SU874175586A SU1572725A1 (ru) 1987-01-21 1987-01-21 Способ очистки металлических полос от окалины
SU4175586 1987-01-21

Publications (2)

Publication Number Publication Date
EP0304490A4 EP0304490A4 (de) 1989-02-09
EP0304490A1 true EP0304490A1 (de) 1989-03-01

Family

ID=21278221

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19880901482 Withdrawn EP0304490A1 (de) 1987-01-21 1988-01-15 Verfahren zum entzundern von flachstahl

Country Status (6)

Country Link
US (1) US4918960A (ru)
EP (1) EP0304490A1 (ru)
JP (1) JPH01502499A (ru)
AU (1) AU607467B2 (ru)
SU (1) SU1572725A1 (ru)
WO (1) WO1988005348A1 (ru)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0523576A1 (de) * 1991-07-19 1993-01-20 Thyssen Stahl Aktiengesellschaft Verfahren und Anlage zum Herstellen eines Metallstranges durch Giessen
CN109746820A (zh) * 2019-01-23 2019-05-14 上海理工大学 管内壁磁性复合流体抛光装置

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1991012096A1 (en) * 1990-02-14 1991-08-22 Cherepovetsky Filial Vologodskogo Politekhnicheskogo Instituta Method for descaling the surface of hot-rolled strip
TWI552812B (zh) * 2012-01-25 2016-10-11 Sms Group Gmbh 製造金屬帶的方法與設備

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56139215A (en) * 1980-03-31 1981-10-30 Mitsubishi Heavy Ind Ltd Descaling method for hot rolled steel strip
JPS56139214A (en) * 1980-03-31 1981-10-30 Mitsubishi Heavy Ind Ltd Descaling method for hot rolled steel strip
GB2173722A (en) * 1984-05-30 1986-10-22 Severo Zapad Zaoch Polt Inst Device for descaling the strip surface

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL177417B (nl) * 1952-04-09 Firestone Tire & Rubber Co Werkwijze voor de bereiding van elastomere polyfosfazeencopolymeren, alsmede uit deze copolymeren vervaardigde voorwerpen.
JPS50107594A (ru) * 1974-01-30 1975-08-25
SU887048A1 (ru) * 1978-08-04 1981-12-07 Череповецкий Филиал Северо-Западного Заочного Политехнического Института Устройство дл очистки поверхностей длинномерных прокатных изделий от окалины
SU889174A2 (ru) * 1978-12-12 1981-12-15 За витель Устройство дл очистки проволоки от окалины
SU1030056A1 (ru) * 1980-01-04 1983-07-23 Череповецкий Филиал Северо-Западного Заочного Политехнического Института Устройство дл очистки полосового проката от окалины ферромагнитным порошком
JPS577315A (en) * 1980-06-16 1982-01-14 Mitsubishi Heavy Ind Ltd Descaling apparatus for steel sheet
SU902378A1 (ru) * 1980-09-22 1988-10-23 Череповецкий Филиал Северо-Западного Заочного Политехнического Института Устройство дл очистки поверхности широких полос от окалины
SU1197752A1 (ru) * 1984-02-09 1985-12-15 Всесоюзный научно-исследовательский институт метизной промышленности Устройство дл очистки длинномерного полосового материала
JPH01500407A (ja) * 1986-08-15 1989-02-16 チェルポヴェツキ　フィリアル　ヴォロゴドスコゴ　ポリテクニチエスコゴ　インスチテュータ 圧延製品の表面からスケールを除去する装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56139215A (en) * 1980-03-31 1981-10-30 Mitsubishi Heavy Ind Ltd Descaling method for hot rolled steel strip
JPS56139214A (en) * 1980-03-31 1981-10-30 Mitsubishi Heavy Ind Ltd Descaling method for hot rolled steel strip
GB2173722A (en) * 1984-05-30 1986-10-22 Severo Zapad Zaoch Polt Inst Device for descaling the strip surface

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Band 6, nr. 20 (M-110)[898], 5. Februar 1982; & JP-A-56 139 214 (MITSUBISHI JUKOGYO K.K.) 30.10.1981 *
PATENT ABSTRACTS OF JAPAN, Band 6, Nr. 20 (M-110)[898], 5. Februar 1982; & JP-A-56 139 215 (MITSUBISHI JUKOGYO K.K.) 30.10.1981 *
See also references of WO8805348A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0523576A1 (de) * 1991-07-19 1993-01-20 Thyssen Stahl Aktiengesellschaft Verfahren und Anlage zum Herstellen eines Metallstranges durch Giessen
CN109746820A (zh) * 2019-01-23 2019-05-14 上海理工大学 管内壁磁性复合流体抛光装置

Also Published As

Publication number Publication date
AU607467B2 (en) 1991-03-07
JPH01502499A (ja) 1989-08-31
AU1248288A (en) 1988-08-10
SU1572725A1 (ru) 1990-06-23
WO1988005348A1 (en) 1988-07-28
US4918960A (en) 1990-04-24
EP0304490A4 (de) 1989-02-09

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