EP0225273B1 - Verfahren und Vorrichtung zum kontinuierlichen Beizen - Google Patents

Verfahren und Vorrichtung zum kontinuierlichen Beizen Download PDF

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Publication number
EP0225273B1
EP0225273B1 EP86730180A EP86730180A EP0225273B1 EP 0225273 B1 EP0225273 B1 EP 0225273B1 EP 86730180 A EP86730180 A EP 86730180A EP 86730180 A EP86730180 A EP 86730180A EP 0225273 B1 EP0225273 B1 EP 0225273B1
Authority
EP
European Patent Office
Prior art keywords
pickling
acid liquid
tank
pickled
acid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP86730180A
Other languages
English (en)
French (fr)
Other versions
EP0225273A1 (de
Inventor
Kenichi Hiroshima Technical Inst. Yanagi
Toshio Hiroshima Technical Inst. Taguchi
Juuji Hiroshima Technical Inst. Furuzawa
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.)
Mitsubishi Heavy Industries Ltd
Original Assignee
Mitsubishi Heavy 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
Priority claimed from JP27343185A external-priority patent/JPS62133090A/ja
Priority claimed from JP27506885A external-priority patent/JPS62136582A/ja
Priority claimed from JP27506785A external-priority patent/JPS62136581A/ja
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Publication of EP0225273A1 publication Critical patent/EP0225273A1/de
Application granted granted Critical
Publication of EP0225273B1 publication Critical patent/EP0225273B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G3/00—Apparatus for cleaning or pickling metallic material
    • C23G3/02—Apparatus for cleaning or pickling metallic material for cleaning wires, strips, filaments continuously
    • C23G3/023—Apparatus for cleaning or pickling metallic material for cleaning wires, strips, filaments continuously by spraying
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
    • C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G3/00—Apparatus for cleaning or pickling metallic material
    • C23G3/02—Apparatus for cleaning or pickling metallic material for cleaning wires, strips, filaments continuously
    • C23G3/027—Associated apparatus, e.g. for pretreating or after-treating
    • C23G3/028—Associated apparatus, e.g. for pretreating or after-treating for thermal or mechanical pretreatment

Definitions

  • the present invention relates to a continious pickling method and apparatus for metallic materials and especially for steel plates.
  • FIG. 10 One embodiment of a conventional continuous pickling apparatus is shown in Fig. 10.
  • reference numeral 101 is a steel strip
  • numeral 102 is an acid tank
  • 103 is an acid liquid
  • 104a, 104b, 104c, 104d and 104e are guide rolls.
  • the steel strip 101 having ordinary temperature is unwound from a payoff reel not shown, and is then caused to run through the acid liquid 103 in the acid tank 102, while a scale formed on the surfaces of the steel strip 4 is pickled out with the acid liquid 103. Afterward, the scale-free steel strip 101 is taken out from the acid tank 102 and is then fed to a subsequent process not shown.
  • An object of the present invention is to provide a continuous pickling method and apparatus by which a period of time necessary for a pickling operation is curtailed, so that a used acid tank is shortened.
  • a first means for achieving the above object is to heat a material to be pickled up to a high temperature. That is, the present invention is directed to a continuous pickling method for continuously pickling a metallic material to be pickled, the method being characterized by heating the material up to a temperature higher than a boiling point of an acid liquid under atmospheric pressure and then pickling the material with said acid liquid of a temperature lower than that of said material to be pickled in said pickling tank.
  • a heating device for heating a steel strip which is a material to be pickled is provided in front of an acid tank, and in the heating device, the steel strip is then heated up to a temperature higher than a boiling point of an acid liquid under atmospheric pressure. Afterward, the steel strip is introduced into the acid tank in order to be subjected to a pickling treatment.
  • the steel strip having a temperature higher than the boiling point of the acid liquid is brought into contact with the acid liquid having a temperature lower than the boiling point.
  • the acid liquid penetrates into fine cracks in a scale on the surfaces of the steel strip, and it boils to generate vapor.
  • a gas is expanded abruptly, so that pieces of the scale are peeled off and new cracks occurs. In this way, the pickling time is curtailed.
  • a second means for achieving the above object is to jet an acid liquid against a previously highly heated material to be pickled. That is, the present invention is directed to a continuous pickling method for continuously pickling a material to be pickled, the method being characterized by heating the material up to a temperature higher than a boiling point of an acid liquid under atmospheric pressure, and then jetting the acid liquid againt the material in an acid tank in order to pickle the material, without immersing the material into the acid liquid.
  • a heating device for heating the steel strip is provided in front of the acid tank, and the steel strip is heated up to a temperature higher than the boiling point of the acid liquid under atmospheric pressure by the heating device. Afterward, the steel strip is introduced into the acid tank, and the acid liquid is jetted against the steel strip material to pickle the latter, without immersing the steel strip material into the acid liquid.
  • the steel strip having a temperature higher than the boiling point of the acid liquid is brought into contact with the acid liquid having a temperature lower than the boiling point.
  • the acid liquid penetrates into fine cracks in a scale on the surfaces of the steel strip, and it boils to generate vapor.
  • a gas is expanded abruptly, so that pieces of the scale are peeled off and new cracks occurs.
  • the jetted acid liquid washes out the pieces of the scale, or the reacted acid liquid is replaced with the new acid liquid to accelerate the reaction, whereby the time necessary for the pickling treatment is curtailed.
  • the jet method of the present invention has a greater jet effect because of the vigor of the jet being maintained, and an advantage of decreasing a necessary amount of the acid liquid owing to immersing no steel strip into the acid liquid.
  • the present invention provides an apparatus for practicing the above mentioned method.
  • the present invention is directed to the use of a pretreating apparatus for continuous pickling which comprises a tank for receiving herein hot water having a temperature higher than its boiling point under atmospheric pressure, a heating device for heating the hot water, and seal rolls disposed at an outlet and an inlet of the tank and a material to be pickled.
  • This apparatus can practice the above mentioned method effectively.
  • a heating device is provided in front of an acid tank, and reference numeral 1 is a steel strip, numeral 2 is an acid tank, 3 is an acid liquid, 4a, 4b, 4c, 4d and 4e are guide rolls, and 6a and 6b are electric type, hot air type or other type heating devices.
  • the steel strip 1 is heated up to a temperature higher than a boiling point of the acid liquid at atmospheric pressure by the heating devices 6a, 6b, and it is then immersed into the acid liquid 3 in the acid tank 2 to pickle the steel strip 1.
  • Fig. 2 exhibits the other embodiment in which a heating water tank 7 is equipped as the heating device.
  • the heating water tank 7 in Fig. 2 is of a sealing type, and pairs of seal rolls 9a, 9b and 9c, 9d are disposed at an outlet and an inlet, respectively, of the steel strip 1 in the heating water tank 7, whereby an opening space between the interior of the heating water tank 7 and the outside is minimized, and the steel strip 1 is allowed to run continuously through the heating tank 7, while a high pressure is retained in the tank 7.
  • a pressurizing water 8 having a high temperature is placed in the heating water tank 7.
  • Numerals 10a, 10b and 10c are guide rolls.
  • the pressurizing water 8 is heated by, for example, a disposed heating device 41 so as to provide the water 8 with a high temperature.
  • Fig. 3 shows the other embodiment.
  • the heating devices 6a and 6b are disposed in front of the acid tank as in the case of Fig. 1, but the acid tank 12 is pressurer-sealed by the seal rolls 5a, 5b and 5c, 5d in order to maintain the interior of the acid tank 12 at a high pressure and to maintain the acid liquid 3 at a temperature higher than its boiling point at atmospheric pressure.
  • the steel strip at the outlet of the heating device 6a, 6b has a higher temperature than the acid liquid 3.
  • 14a, 14b and 14c are guide rolls.
  • Fig. 4 is the further other embodiment of the present invention.
  • the apparatus in Fig. 4 is equipped with the same acid tank 12 as in Fig. 3, but the same heating water tank 7 as in Fig. 2 is provided as the heating device in front of the acid tank. That is, numeral 8 is a pressurizing water having a high temperature, 9a, 9b, 9c and 9d are seal rolls, and 10a, 10b and 10c are guide rolls.
  • the steel strip is first heated up to a temperature higher than the boiling point of the acid liquid at atmospheric pressure and is then immersed into the acid liquid. Therefore, at the moment when the steel strip is immersed into the acid liquid, the latter penetrates into fine cracks in a scale on the surfaces of the steel strip, and it boils to generage vapor, which fact leads to the abrupt expansion of a gas. As a result, pieces of the scale are peeled off and new cracks occur, so that a time necessary for the pickling operation is curtailed. According to experiments made by the inventors of the present application, the higher the temperature of the steel plate is, the shorter the time necessary for the pickling operation is, as shown in Fig. 5.
  • the pickling time necessary for the steel plate of 80 °C is regarded as 100 %
  • the pickling time for the steel plate of 200 °C is 50 % or less.
  • the similar effect can be obtained by heating the steel plate up to a level higher than the liquid temperature.
  • a heating device is provided in front of an acid tank, and reference numeral 1 is a steel strip, numeral 22 is an acid tank, 3 is an acid liquid, 24a, 24b, 24c and 24d are guide rolls.
  • Numerals 6a and 6b are electric type, hot air type or other type heating devices, as shown in Fig. 3.
  • the steel strip 1 is heated up to a temperature higher than a boiling point of the acid liquid at atmospheric pressure by the heating devices 6a, 6b, and is then introduced into the acid tank 22.
  • the steel strip 1 is subjected to a pickling treatment by jetting the acid liquid, fed by a pump not shown, against both the surfaces of the steel strip 1 through nozzles 11 a, 11 b, 11 c, « and 111, while supported by the guide rolls 24a, 24b, 24c and 24d, without being immersed into the acid liquid 3.
  • Fig. 7 shows the other embodiment of the present invention, and in this embodiment, the same heating water tank 7 as in Fig. 4 is equipped.
  • Figs. 8 and 9 show other embodiments of an acid tank portion regarding the present invention:
  • the embodiment in Fig. 8 has shield plates 12a, 12b, 12c, whil and 121 which closely confront the upper and lower surfaces of the steel strip 1 so as to define. a flow path for the acid liquid between these shield plates and the steel strip 1.
  • the acid liquid jetted through nozzles 11 a, 11 b, 11 c, « and 111 flows through the aforesaid flow path, so that a contact time between the acid liquid and the steel strip 1 is prolonged, and a velocity of the acid liquid along the steel strip 1 is kept up, thereby assuring an effective pickling reaction.
  • the embodiment in Fig. 9 has box shields 13a, 13b, ... which are shaped so as to surround the steel strip 1, and in this case, a flow path is defined between the box shields and the steel strip 1.
  • the acid liquid does not flow out in a cross direction of the steel strip, so that an effect of the acid liquid increases additionally.
  • the material to be pickled after heated up to a high temperature, is pickled, as described in detail above. Therefore, at the moment when the steel strip is immersed into the acid liquid, the latter penetrates into fine cracks in a scale on the surface of the steel strip, and it boils to generage vapor, which fact leads to the abrupt expansion of a gas. As a result, pieces of the scale are peeled off -and new cracks occur, so that a time necessary for the pickling operation can be curtailed. Further, in consequence, the acid tank car be shortened. This is an effect of the present invention.
  • the steel strip is heated as described above, and the acid liquid is then jetted against the heated steel strip, instead of being immersed into the acid liquid. Therefore, at the moment when the acid liquid is jetted against the steel strip, the acid liquid penetrates into fine cracks in a scale on the surface of the steel strip, and it boils to generage vapor, which fact leads to the abrupt expansion of a gas. As a result, pieces of the scale are peeled off and new cracks occur, and the jet of the acid liquid washes out the peices of the scale, so that a time necessary for the pickling operation is curtailed. According to experiments made by the present inventors, the time necessary for the pickling treatment in the present invention is about 1/3 of that of the conventional pickling treatment in which neither heating nor jetting are carried out.
  • the material to be pickled for example, the steel strip can be heated up to the temperature higher than the boiling point of the acid liquid at atmospheric pressure. Therefore, the method of the present invention can surely be practiced as described above, thereby curtailing the pickling time and shortening the acid tank.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)

Claims (7)

1. Verfahren zum kontinuierlichen Beizen durch kontinuierliches Einbringen eines zu beizenden metallischen Werkstoffs in einen eine saure Beizflüssigkeitskonzentration enthaltenden Beiztank, dadurch gekennzeichnet, daß der zu beizende Werkstoff auf eine höher als der Siedepunkt der Säureflüssigkeit liegenden Temperatur unter atmosphärischen Druck erwärmt und dann mit der Säureflüssigkeit einer niedriger als der des zu beizenden Werkstoffs im Beiztank liegenden Temperatur gebeizt wird.
2. Verfahren zum kontinuierlichen Beizen nach Anspruch 1, dadurch gekennzeichnet, daß die Wärmebehandlung vor dem Beizen durchgeführt wird mittels einer elektrisch oder mit Heißluft betriebenen Heizvorrichtung oder eines heizenden Wassertanks.
3. Verfahren zum kontinuierlichen Beizen durch kontinuierliches Einbringen eines zu beizenden metallischen Werkstoffs in einen eine saure Beizflüssigkeitskonzentration enthaltenden Beiztank sowie durch Spritzen einer Säureflüssigkeit auf den Werkstoff im Beiztank, um den Werkstoff zu beizen, gekennzeichnet durch Erwärmen des Werkstoffs auf eine höher als der Siedepunkt der Säureflüssigkeit liegende Temperatur und durch nachfolgendes Aufsprühen auf den Werkstoff auf den eingespritzten Strom der Säureflüssigkeit von einer niedriger als der des vorerhitzten Werkstoffs liegenden Temperatur.
4. Verfahren zum kontinuierlichen Beizen nach Anspruch 3, dadurch gekennzeichnet, daß die Wärmebehandlung vor dem Beizen durchgeführt wird mittels einer elektrisch oder mit Heißluft betriebenen Heizvorrichtung oder eines heizenden Wassertanks.
5. Verfahren zum kontinuierlichen Beizen nach Anspruch 3, dadurch gekennzeichnet, daß beim Spritzen der Säureflüssigkeit auf den zu beizenden Werkstoff Abschirmbleche sehr nahe an den Ober- und Unterflächen des Werkstoffs angeordnet sind.
6. Verfahren zum kontinuierlichen Beizen nach Anspruch 3, dadurch gekennzeichnet, daß beim Spritzen der Säureflüssigkeit auf den zu beizenden Werkstoff der Werkstoff von Kastenabschirmungen umgeben ist.
7. Vorrichtung zum Durchführen des Verfahrens nach den Ansprüchen 1 bis 6, dadurch gekennzeichnet, daß die Beizvorrichtung einen Vorwärmer und einen Beiztank aufweist, wobei der Vorwärmer eine Heizvorrichtung und einen Heißwassertank zum Erhitzen des Wassers im Tank auf eine höher als dessen Siedepunkt liegende Temperatur unter atmosphärischen Druck sowie Dichtungsrollen besitzt, die am Ausgang und Eingang des Heißwassertanks liegen.
EP86730180A 1985-12-06 1986-11-03 Verfahren und Vorrichtung zum kontinuierlichen Beizen Expired - Lifetime EP0225273B1 (de)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP27343185A JPS62133090A (ja) 1985-12-06 1985-12-06 連続酸洗前処理装置
JP273431/85 1985-12-06
JP27506885A JPS62136582A (ja) 1985-12-09 1985-12-09 連続酸洗方法
JP275068/85 1985-12-09
JP275067/85 1985-12-09
JP27506785A JPS62136581A (ja) 1985-12-09 1985-12-09 連続酸洗方法

Publications (2)

Publication Number Publication Date
EP0225273A1 EP0225273A1 (de) 1987-06-10
EP0225273B1 true EP0225273B1 (de) 1990-03-28

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP86730180A Expired - Lifetime EP0225273B1 (de) 1985-12-06 1986-11-03 Verfahren und Vorrichtung zum kontinuierlichen Beizen

Country Status (5)

Country Link
EP (1) EP0225273B1 (de)
KR (1) KR870006236A (de)
AU (1) AU594988B2 (de)
BR (1) BR8605681A (de)
DE (1) DE3669898D1 (de)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62136583A (ja) * 1985-12-09 1987-06-19 Mitsubishi Heavy Ind Ltd 連続酸洗装置
US5466309A (en) * 1993-02-12 1995-11-14 Clecim Metal strip treatment installation
FR2701493B1 (fr) * 1993-02-12 1995-08-25 Clecim Sa Installation de décapage d'une bande métallique.
FR2701410B1 (fr) * 1993-02-12 1995-05-05 Clecim Sa Installation de décapage d'une bande métallique.
KR100396062B1 (ko) * 2000-07-13 2003-08-27 연합철강공업 주식회사 강판의 스케일을 제거하는 방법
AT500729B8 (de) * 2004-12-14 2007-02-15 Voest Alpine Ind Anlagen Beizeinrichtung und verfahren zum kontinuierlichen beizen eines metallbandes
CN102644087B (zh) * 2012-04-17 2014-04-16 安徽鑫科新材料股份有限公司 一种用于成品扁线在线酸洗的皂化槽及其酸洗方法
CN105483741A (zh) * 2015-12-08 2016-04-13 无锡华工薄板有限公司 一种带钢用酸洗槽的控温装置

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1031175A (en) * 1962-04-06 1966-05-25 Heurtey Sa Apparatus for treating steel strip, especially to prepare it for metallization and galvanization operations
AU1112266A (en) * 1966-09-15 1968-03-21 Albert Paul Schmidsrauter Process and apparatus forde-scaling metal articles
JPS5334167B1 (de) * 1968-08-17 1978-09-19
US3617039A (en) * 1968-04-26 1971-11-02 Mitsubishi Heavy Ind Ltd Descaling apparatus for steel
JPS62136583A (ja) * 1985-12-09 1987-06-19 Mitsubishi Heavy Ind Ltd 連続酸洗装置

Also Published As

Publication number Publication date
AU6550186A (en) 1987-06-11
BR8605681A (pt) 1987-08-18
KR870006236A (ko) 1987-07-10
AU594988B2 (en) 1990-03-22
DE3669898D1 (de) 1990-05-03
EP0225273A1 (de) 1987-06-10

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