EP0282759A1 - Verfahren zur Wiederherstellung der inneren Wände einer Stranggiesskokille - Google Patents

Verfahren zur Wiederherstellung der inneren Wände einer Stranggiesskokille Download PDF

Info

Publication number
EP0282759A1
EP0282759A1 EP88102498A EP88102498A EP0282759A1 EP 0282759 A1 EP0282759 A1 EP 0282759A1 EP 88102498 A EP88102498 A EP 88102498A EP 88102498 A EP88102498 A EP 88102498A EP 0282759 A1 EP0282759 A1 EP 0282759A1
Authority
EP
European Patent Office
Prior art keywords
copper
crystallizer
bath
anode
electrodeposition
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Withdrawn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
EP88102498A
Other languages
English (en)
French (fr)
Inventor
Gianpietro Miani
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.)
Danieli and C Officine Meccaniche SpA
Original Assignee
Danieli and C Officine Meccaniche SpA
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 Danieli and C Officine Meccaniche SpA filed Critical Danieli and C Officine Meccaniche SpA
Publication of EP0282759A1 publication Critical patent/EP0282759A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
    • B22D11/059—Mould materials or platings

Definitions

  • This invention concerns a method for the rehabilitation of a crystallizer employed in plants carrying out the continuous casting of steel or other products.
  • the molten metal coming from a smelting furnace and collected in a ladle is passed through one or more ingot moulds suitably arranged to obtain superficial cooling of the molten mass; the cooling thereafter proceeds during the successive casting steps.
  • a continuous casting ingot mould consists of a steel cooling jacket, in which a cooling liquid (usually water) is circulated, and of an inner tubular assembly, which comes into contact with the incandescent mass and is called a "crystal­lizer".
  • a cooling liquid usually water
  • This crystallizer is usually made of copper and may consist of one single piece or of suitably dimensioned plates placed side by side. It has to be shaped also with its lower end tapered so as to take account of the progressive dimensional shrinkage of a bar while cooling.
  • the crystallizer Being in contact with the molten mass at a very high temperature and with the solidified skin of the metal being cast, the crystallizer undergoes considerable wear and therefore after a given number of working cycles, can be employed no longer and has to be replaced with a new crystallizer.
  • One known rehabilitation system is based on mechanical pressing; in fact, the crystallizer is compressed uniformly about a gauge which has outer dimensions the same as the corresponding inner dimensions of the crystallizer.
  • the inner surface of the crystallizer is restored by means of this system, but its thickness is reduced thereby so that a play between the outer wall of the crystallizer and the inner wall of the cooling jacket surrounding the crystallizer is produced which is such as to prevent perfect contact between those walls.
  • Document DE-A-2.936.177 discloses a process for the treatment of the walls of a crystallizer by means of galvanic or electrolytic solutions.
  • the crystallizer wall thus conformed is supported on the inner surface of a first container suitable to be filled with a galvanic solution.
  • This first container is provided with an anode positioned in front of the inner wall of the crystal­lizer and is connected to a second container which recovers and heats the solution.
  • the process described in this document does not provide for any treatment of the inner wall of the crystallizer nor, in particular, for any treatment of the copper wall which is to receive the casting of molten metal ; instead, it provides for a treatment of the outer surfaces of the plates.
  • this process requires a special arrangement of the plates on the first container and is not suitable for the treatment of a whole crystallizer in one single electro-­deposition.
  • Document DE-A-3.231.444 discloses a process for the rehabilitation of crystallizers made of copper or a nickel-­based copper alloy in which the layer of nickel is removed and a new layer of nickel covers the copper.
  • This process provides for the filing of a part of the layer of nickel, an alkaline degreasing bath and an acid activating bath based on sulphuric or phosphoric acid. Another layer of nickel is deposited thereafter on the surface thus freed.
  • the purpose of this invention is to rehabilitate an ingot mould crystallizer and/or the plates of which it consists by restoring its inner surfaces perfectly and leaving its outer surfaces unchanged.
  • This purpose is achieved by a method to rehabilitate the inner surfaces of an ingot mould crystallizer and/or the plates forming the walls of an ingot mould crystallizer according to Claim 1.
  • the method according to this invention provides for the following steps of preparation and thorough cleaning:-
  • the method according to the invention provides for the following finishing steps on the crystallizer after the copper plating:
  • a further plating step with the electrodeposition of other metals may be included with the purpose of prolonging as much as possible the working life of the crystallizer thus rehabilitated in the subsequent re-use thereof in continuous casting plants.
  • the crystallizer must be checked first of all to ensure its suitability for rehabilitation.
  • a crystallizer 30 which may be tubular with a square section as shown in Fig.1, for instance, has inner scoring 2 filled with soldered metal.
  • the crystallizer has its inner surfaces smooth, as shown in Fig.2.
  • Fig.3 shows a crystallizer of which the surface covered with an inert film material 3 is marked with dashes.
  • the surfaces to be copper plated are honed next to remove any strains due to the earlier mechanical processes and to impart to the surfaces the proper roughness (Fig.4) for fixture of the player of copper.
  • the crystallizer 30 undergoes anodic electrolysis in a base solution 31 with the use of an anode 33 (Fig.5) and thereafter is activated in an acid solution 32 with the use of an anode 34 (Fig.6).
  • the anodic electrolysis eliminates saponifiable fats from the surface, whereas the activation eliminates any traces of oxide, thus making the surfaces active and putting the grains of copper in the crystallizer into the best condition for being bonded with the new layer which will be electro­deposited on those grains.
  • the cathode 12 consists of the crystallizer itself, while the anode 13 is a suitably shaped titanium frame.
  • the frame shown in Fig.7 has been dimensioned for a crystallizer having an almost square shape and comprises a tubular portion 14 the walls of which are provided with a plurality of holes 15 (Fig.8) and with protrusions 16, which also contain holes and are arranged like a spider of spokes about the tubular portion 14.
  • the inside of the tubular portion 14 and the spokes 16 are filled with small blocks 17 of copper shaped as cubes or disks.
  • the anode 13 consists of a titanium frame which, instead of containing blocks of copper, is coated with an adequate layer of copper 18.
  • a suitable round anode will be employed with round tubular crystallizers, while it will be enough to place the crystallizer plates in front of anodes which may consist of a set of titanium baskets filled with copper cubes or of copper bars of a suitable chemical composition.
  • the bath 11 prepared in the vessel 10 holds the following compounds, of which the respective fields of values of the contents are given: - copper suphate (CuSO4 x 5H2O) from 150 to 280 grs/lt - sulphuric acid (H2SO4) from 30 to 90 grs/lt - antipitting agent from 0.3 to 0.8 gr/lt - anode activation and polishing agent from 0.3 to 0.8 gr/lt
  • a typical bath will contain the following quantities of the above compounds: - copper sulphate (CuSO4 x 5H2O) about 220 grs/lt - sulphuric acid (H2SO4) about 70 grs/lt - antipitting agent about 0.4 gr/lt - anode activation and polishing agent about 0.4 gr/lt
  • the copper sulphate makes available the cupric ions (Cu++) required for the electrodeposition.
  • the sulphuric acid prevents the formation of base copper salts which would form a very friable coating, and also increases the conductivity of the bath and assists the formation of fine-grain deposits.
  • the antipitting agent performs the action of reducing the surface tension of the bath and enhances the levelness of the layer deposited.
  • the activation agent reduces the sizes of the grains and has a depolarising effect on the copper anodes.
  • the average conditions of a typical bath will be, for instance, as follows: - temperature 30 ⁇ 10°C - current density 6 A/sq.dm. - stirring with air 0.2 lt/min. per litre of inner volume of the crystallizer - continuous filtration 10 ⁇ .
  • steps are taken to wrap the anode 13 in a Meraclon, Terylene or polypropylene, etc. cloth so as not to pollute the bath; the anode is then placed within the crystallizer to be copper plated, and the whole is immersed in the vessel 10.
  • the copper in the copper sulphate solution is deposited on the cathode and the copper in the solution thus consumed is balanced by dissolution of the anode.
  • the length of the duration of this process will vary according to the thickness of the layer of the copper to be restored but it will generally last between ten and twenty hours.
  • the duration of the electrodeposition is such that the layer deposited is thicker than the final layer required, this being necessary for the purposes of the successive processes. In general an excess of at least 0.2 to 0.3 mm. per surface is required.
  • the concentration of copper ions will increase, and therefore at the end of each electrodeposition process it is best to remove the anode 13 or anodes from the bath.
  • the inert material 3 covering the surfaces not copper plated is removed and the crystallizer then undergoes grinding to obtain the exact dimensions required.
  • the line of dashes 21 and continuous line 22 indicate diagrammatically the profile of the crystallizer before the electrodeposition step, whereas the inner continuous line 23 indicates the final inner profile.
  • the overall crystallizer is referenced with 30.
  • the method provides also, preferably, before removal of the inert material 3, a further final step of internal coating to give the crystallizer better properties.
  • a first type of coating consists of nickel plating followed by chromium plating.
  • Another type of coating arranges to interpose, between the nickel plating and chromium plating, an electrodeposition of a layer of an alloy consisting of nickel and phosphorus; this alloy possesses excellent abrasion resistance and, through thermal effect, reaches more than 70° Rockwell hardness.
  • the crystallizer shown in Fig.11 is the final product obtained with the method described; the reference No.20 in this figure indicates the final multiple coating.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Electroplating Methods And Accessories (AREA)
  • Continuous Casting (AREA)
EP88102498A 1987-03-18 1988-02-20 Verfahren zur Wiederherstellung der inneren Wände einer Stranggiesskokille Withdrawn EP0282759A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT1973887 1987-03-18
IT8719738A IT1215386B (it) 1987-03-18 1987-03-18 Procedimento di recupero per cristallizzatore di lingottiera per colata continua.

Publications (1)

Publication Number Publication Date
EP0282759A1 true EP0282759A1 (de) 1988-09-21

Family

ID=11160811

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88102498A Withdrawn EP0282759A1 (de) 1987-03-18 1988-02-20 Verfahren zur Wiederherstellung der inneren Wände einer Stranggiesskokille

Country Status (2)

Country Link
EP (1) EP0282759A1 (de)
IT (1) IT1215386B (de)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0492264A1 (de) * 1990-12-24 1992-07-01 Sms Schloemann-Siemag Aktiengesellschaft Stahlstranggiesskokille
EP1345720A1 (de) * 2000-09-11 2003-09-24 SMS Demag, Inc. System und verfahren zur optimierung der kühlung in stranggiesskokillen
CN105177656A (zh) * 2015-10-19 2015-12-23 姜少群 一种结晶器铜管电镀铬的单质镍过渡层
EP2393965B1 (de) 2009-09-29 2016-06-08 Egon Evertz K.G. (GmbH & CO) Kokille zum stranggiessen
CN109355684A (zh) * 2018-11-28 2019-02-19 德阳深捷科技有限公司 一种应用于连铸结晶器的增材制造结构及增材制造方法和装置
CN115110018A (zh) * 2022-06-22 2022-09-27 武汉钢铁有限公司 结晶器铜板用涂层的制备方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3186925A (en) * 1960-11-01 1965-06-01 Gen Motors Corp Chromium plating process with a pure nickel strike
DE2063632A1 (de) * 1969-12-31 1971-07-08 Sifco Ind Inc Verfahren zum Reparieren einer beschädigten Stelle einer chromplattierten Oberflache
DE3215689A1 (de) * 1981-04-27 1982-11-18 Satosen Co. Ltd., Osaka Kokille fuer das stranggiessen von stahl
DE3231444A1 (de) * 1981-09-01 1983-08-11 Mishima Kosan Corp., Kitakyushu, Fukuoka Verfahren zum ausbessern von kokillen fuer den strangguss von stahl

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3186925A (en) * 1960-11-01 1965-06-01 Gen Motors Corp Chromium plating process with a pure nickel strike
DE2063632A1 (de) * 1969-12-31 1971-07-08 Sifco Ind Inc Verfahren zum Reparieren einer beschädigten Stelle einer chromplattierten Oberflache
DE3215689A1 (de) * 1981-04-27 1982-11-18 Satosen Co. Ltd., Osaka Kokille fuer das stranggiessen von stahl
DE3231444A1 (de) * 1981-09-01 1983-08-11 Mishima Kosan Corp., Kitakyushu, Fukuoka Verfahren zum ausbessern von kokillen fuer den strangguss von stahl

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
J.K. DENNIS et al.: "Nickel and chromium plating", 1972, pages 65-66, Newnes, Butterworths, London, GB *
PATENT ABSTRACTS OF JAPAN, vol. 6, no. 45 (M-118)[923], 20th March 1982; & JP-A-56 160 857 (NOMURA TOKIN K.K.) 10-12-1981 *
PATENT ABSTRACTS OF JAPAN, vol. 7, no. 169 (M-231)[1314], 26th July 1983; & JP-A-58 074 252 (MISHIMA KOUSAN K.K.) 04-05-1983 *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0492264A1 (de) * 1990-12-24 1992-07-01 Sms Schloemann-Siemag Aktiengesellschaft Stahlstranggiesskokille
EP1345720A1 (de) * 2000-09-11 2003-09-24 SMS Demag, Inc. System und verfahren zur optimierung der kühlung in stranggiesskokillen
EP1345720A4 (de) * 2000-09-11 2006-03-22 Sms Demag Inc System und verfahren zur optimierung der kühlung in stranggiesskokillen
EP2393965B1 (de) 2009-09-29 2016-06-08 Egon Evertz K.G. (GmbH & CO) Kokille zum stranggiessen
CN105177656A (zh) * 2015-10-19 2015-12-23 姜少群 一种结晶器铜管电镀铬的单质镍过渡层
CN105177656B (zh) * 2015-10-19 2018-03-16 永春县达埔文雅家庭农场 一种结晶器铜管电镀铬的单质镍过渡层
CN109355684A (zh) * 2018-11-28 2019-02-19 德阳深捷科技有限公司 一种应用于连铸结晶器的增材制造结构及增材制造方法和装置
CN115110018A (zh) * 2022-06-22 2022-09-27 武汉钢铁有限公司 结晶器铜板用涂层的制备方法
CN115110018B (zh) * 2022-06-22 2023-11-10 武汉钢铁有限公司 结晶器铜板用涂层的制备方法

Also Published As

Publication number Publication date
IT1215386B (it) 1990-02-08
IT8719738A0 (it) 1987-03-18

Similar Documents

Publication Publication Date Title
CA2600645C (en) Stainless steel electrolytic plates
EP0282759A1 (de) Verfahren zur Wiederherstellung der inneren Wände einer Stranggiesskokille
US5788824A (en) Process for conditioning the copper or copper-alloy external surface of an element of a mold for the continuous casting of metals, of the type including a nickel plating step and a nickel removal step
CA1200362A (en) Molds for continuously casting steel
US6531039B2 (en) Anode for plating a semiconductor wafer
AU710657B2 (en) Component of a mould for the continuous casting of metals, comprising a cooled copper or copper-alloy wall having a metallic coating on its external surface, and process for coating it
EP0383934A1 (de) Giessform für kontinuierlich gegossenen stahl
AU567973B2 (en) Electrode for electrometallurgical process.
JP2975027B2 (ja) 連続鋳造鋳型
JPS61129257A (ja) 連続鋳造用鋳型の製法
JPH0659523B2 (ja) 連続鋳造用鋳型の製造方法
JP2759208B2 (ja) シエル鋳型造型用金型
US4543227A (en) Method of treating refractory boride shapes
JPS58212840A (ja) 連続鋳造用鋳型
MXPA99000426A (en) Element of lingotera for the continuous demetales colada, comprising a refrigerated copper wall, which brings into its outer surface a metallic covering, and procedure for its revestimie
KR20200048160A (ko) 주형 및 이의 제조 방법
US3449224A (en) Nickel electrodeposition process and auxiliary nickel anode alloy
AU2006222554A1 (en) Stainless steel electrolytic plates
JP2004237315A (ja) 連続鋳造用鋳型
JPS5823539A (ja) 鉄鋼連続鋳造用鋳型
JPS5956592A (ja) 電鋳型
JPS60111746A (ja) 連続鋳造用回転円筒補修方法
JPS63157896A (ja) 連続鋳造用鋳型の製造方法
Miani Method for the Rehabilitation of a Crystallizer of a Continuous Casting Ingot Mould
JPH09285846A (ja) 電解コンデンサ電極箔用アルミニウム合金板の製造方法

Legal Events

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

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

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

17P Request for examination filed

Effective date: 19890220

17Q First examination report despatched

Effective date: 19900430

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

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Withdrawal date: 19900723

R18W Application withdrawn (corrected)

Effective date: 19900723