EP2927343A1 - Installation and method for pickling and metal coating of a metal strip - Google Patents
Installation and method for pickling and metal coating of a metal strip Download PDFInfo
- Publication number
- EP2927343A1 EP2927343A1 EP14290086.9A EP14290086A EP2927343A1 EP 2927343 A1 EP2927343 A1 EP 2927343A1 EP 14290086 A EP14290086 A EP 14290086A EP 2927343 A1 EP2927343 A1 EP 2927343A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- strip
- metal
- unit
- temperature
- pickling
- 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- Withdrawn
Links
- 239000002184 metal Substances 0.000 title claims abstract description 60
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 60
- 239000011248 coating agent Substances 0.000 title claims abstract description 48
- 238000000576 coating method Methods 0.000 title claims abstract description 48
- 238000009434 installation Methods 0.000 title claims abstract description 28
- 238000005554 pickling Methods 0.000 title claims abstract description 25
- 238000000034 method Methods 0.000 title claims description 28
- 230000009467 reduction Effects 0.000 claims abstract description 33
- 238000001953 recrystallisation Methods 0.000 claims abstract description 11
- 238000010438 heat treatment Methods 0.000 claims description 24
- 230000008569 process Effects 0.000 claims description 14
- 238000000137 annealing Methods 0.000 claims description 11
- 238000001816 cooling Methods 0.000 claims description 11
- 230000004048 modification Effects 0.000 claims description 10
- 238000012986 modification Methods 0.000 claims description 10
- 238000011144 upstream manufacturing Methods 0.000 claims description 7
- 238000004140 cleaning Methods 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 5
- 238000009987 spinning Methods 0.000 claims description 5
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- 238000012423 maintenance Methods 0.000 claims description 3
- 230000001590 oxidative effect Effects 0.000 claims description 3
- 238000010791 quenching Methods 0.000 claims description 3
- 230000000171 quenching effect Effects 0.000 claims description 3
- 230000001680 brushing effect Effects 0.000 claims description 2
- 238000005238 degreasing Methods 0.000 claims description 2
- 230000007423 decrease Effects 0.000 claims 1
- 238000005246 galvanizing Methods 0.000 description 13
- 238000005097 cold rolling Methods 0.000 description 12
- 229910000831 Steel Inorganic materials 0.000 description 7
- 238000007598 dipping method Methods 0.000 description 7
- 239000010959 steel Substances 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 6
- 229910001338 liquidmetal Inorganic materials 0.000 description 5
- 238000005096 rolling process Methods 0.000 description 5
- 238000009749 continuous casting Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 235000021183 entrée Nutrition 0.000 description 4
- 238000005530 etching Methods 0.000 description 4
- 238000005482 strain hardening Methods 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000000295 complement effect Effects 0.000 description 2
- 238000010924 continuous production Methods 0.000 description 2
- 239000000839 emulsion Substances 0.000 description 2
- 238000005098 hot rolling Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002161 passivation Methods 0.000 description 2
- 239000011343 solid material Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 239000003599 detergent Substances 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 235000008373 pickled product Nutrition 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000004513 sizing Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0278—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips involving a particular surface treatment
-
- 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
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/003—Apparatus
- C23C2/0038—Apparatus characterised by the pre-treatment chambers located immediately upstream of the bath or occurring locally before the dipping process
-
- 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
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
-
- 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
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
- C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
-
- 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
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
- C23C2/024—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by cleaning or etching
-
- 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
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/34—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the shape of the material to be treated
- C23C2/36—Elongated material
- C23C2/40—Plates; Strips
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
Definitions
- the present invention relates to a pickling and metal coating plant of a metal strip according to the preamble of claim 1 and to a related method according to the preamble of claim 12.
- hot-rolled steel lines make it possible to supply metal strips with a thickness generally greater than about 1.2 mm.
- These lines require conventionally, the combination of a continuous casting delivering products whose thickness of about 200 to 250 mm, requires the use of a set of hot mill stands to obtain a sharp reduction in thickness. especially when one wants to reach minimum thicknesses of about 1mm.
- the energy balance and the sizing of such facilities to achieve this result are relatively heavy.
- new hot metal continuous casting processes of the ESP (Endless Strip Production) type make it possible to obtain, with the aid of a smaller set of hot rolling mill stands, steel strips of minimum thickness around 0.7 mm to date.
- the belts have at least one continuous casting line coupled to a set of hot rolling cages and at the output to a strip winder system. These strips are thus delivered in so-called "hot" coils with an oxidized surface, that is to say in the form of coils of non-stripped strips.
- the strips obtained by the "hot” processes described above should be further etched and finally galvanized.
- the output thickness of its produced strips would then be at least generally greater than 1.2 mm with the conventional hot processing routes.
- galvanized for example of smaller thickness and also with good stamping properties, it is necessary to cold roll these strips under sharp reduction in thickness.
- Cold rolling thus induces a hardening of the steel, compared to a low original level of said work hardening, it however offers the advantage of participating in obtaining good final stamping properties, but requires, downstream of rolling operation, to anneal the rolled metal strip, before galvanizing, in order to obtain, in particular, the good stamping properties in the end.
- An example of a galvanizing line for incoming cold-rolled, annealed and then galvanized strips is described by US4436292A .
- the quality of the galvanizing coating such as, for example, the process of dipping in a hot bath and spinning according to US6761936B1 , will not be optimized in terms of surface roughness and flatness of the band.
- the output band will certainly not have good stamping properties.
- This installation has the disadvantage because of the lack of the cold rolling operation, not being able to deliver galvanized products of reduced thickness (for example in a range of 0.5 mm to 5 mm), while maintaining the mechanical strength properties of the product exiting substantially equivalent to the product entering.
- the metal strip subjected to a cold rolling thickness reduction operation the said reduction remaining even limited to 10% and the rolling being not followed by a downstream annealing, the reduction is not appropriate to allow to obtain optimum qualities of galvanized strip in that: firstly the resistance of the coated layer may be substantially degraded by the effects of differential forces and elongation of the rolling between substrate and reported layer; on the other hand, tape drawing properties may be poor due to a lack of downstream annealing, especially for high rates of thickness reduction.
- An object of the present invention is therefore to propose a solution to widen a range of thicknesses of outgoing products of a continuous metal coating process fed by default by a non-stripped steel strip in scrolling, coils developed by a hot process.
- the proposed solution must also ensure that the input web of the coating unit has a minimum rate of work hardening, even if a reduction in web thickness to expand said range, is performed.
- this solution must make it possible to dispense with a step of reduction of high thickness by cold rolling involving a step of annealing the strip (recrystallization), while still allowing to maintain good qualities of stamping of the product. final.
- the present invention must provide a continuous combined process of steps combining pickling, thickness reduction, improvement of roughness and flatness, maintenance of the optimum properties of the material after the thickness reduction, and the deposition of the metal coating.
- the metal coating is mainly a galvanization on the strip such as for example by a method of hot dipping in a bath of liquid metal comprising various types of metal alloys for galvanic protection of the steel, followed by associated treatments to ensure the quality market for coated products. It is also possible to provide any other method of metal coating, such as galvanizing in a suitable electrolytic bath.
- the furnace under atmosphere generally non-oxidizing
- the furnace under atmosphere generally non-oxidizing
- the installation advantageously allows balancing between the effects of (limited) thickness reduction over a larger range and the guarantee of a mastery of possible strip restoration in order to guarantee high qualities of outgoing strip stamping ( minimized work hardening effect by restoration).
- a cleaning unit installed downstream of the skin pass will also remove any emulsions / detergents or other alkaline products, as well as dust (fine iron) and other metal debris possibly generated by the action of the skin pass, this is to improve the quality of the coating.
- the skin-pass only proceeds with a small elongation (or reduction in thickness) and
- it provides a galvanized strip having in particular excellent stamping properties.
- a post-coating step is also provided for simple or combined operations by means of a complementary skin-pass and a tensioning machine, said operation being followed by a complementary coating step (such as a passivation step). ).
- a set of subclaims also has advantages of the invention.
- an inlet section (1) allows the introduction of the strip into said unit by means of two uncoiling machines (1a, 1b) successively pulling the coils towards a strip shear and a welder (11) for welding heads and tails of two successive strips, as well as an accumulator (not shown) for adapting the tape running speed during a welding, and then for introducing the welded webs into the web.
- pickling unit (2) A descaling means ("oxide breeze") is also disposed prior to web entry into the pickling unit (2).
- the pickling unit (2) may comprise successively juxtaposed acid baths, as well as rinsing and drying means. It may alternatively comprise a projection system on the product of a stripping compound such as by means of an abrasive solid material and, if necessary, a liquid.
- abrasive solid material comprises for example particles and / or solid grains and the liquid, if necessary, comprises at least water.
- the metal strip entering the stripping unit is by default a hot-rolled product having a minimum thickness of a few tenths of a millimeter.
- the metal strip upstream of the pickling unit could also be a cold rolled product replacing the hot rolled product, in which case the strip is not pickled in the stripping unit (or deviated from the unit).
- stripping to the skin-pass) and the furnace provides additional heating and cooling means for band annealing.
- this alternative is not described further in the context of the invention, because even if it has a flexibility of switching between "hot” or “cold” strips to be coated surface for example to galvanize them, it requires that the oven allows again an annealing, either that it is accepted to maintain high values of hardness due to cold rolling work hardening.
- the installation according to the invention provides that the skin-pass (3) disposed at the outlet of the pickling unit (2) allows a thickness reduction factor of 0.1% to at least 30%.
- the output of the skin-pass is coupled to a cleaning unit (31) of the strip comprising at least one of the cleaning means among a degreasing (if the reduction rate greater than about 10% which would require the use of emulsion of oil-water type when rolling in skin-pass), brushing, watering, spinning, drying.
- the skin-pass uses working cylinders with defined roughness adapted to the desired degree of roughness on the strip after operations of the rolls, to ensure the best adhesion of the subsequent coating on the strip.
- the type of skin-pass installed can be monocage even include two juxtaposed cages.
- the strip thus enters the furnace (4) successively comprising at least one of the heating means among inductors or other heating means, radiant tubes or other means for maintaining temperature, at least an additional area of rapid heating means and / or rapid cooling.
- These heating means may have various dynamics of heating or cooling the band according to the requirements of the heat treatment according to the invention.
- the oven is ideally placed under a non-oxidizing atmosphere.
- a section of the furnace comprises means for heating the strip ensuring a maintenance of the strip temperature under a threshold temperature of at least partial recrystallization of the strip, ideally under a controllable temperature plateau between 300 ° C. ° C and 700 ° C for less than two minutes.
- the oven can finally raise the required strip outlet temperature before entering the metal coating unit by hot dipping around 500 ° C for conventional galvanizing, and then to fall below this value, ideally towards 465 ° C for a liquid bath of galvanization (this temperature may vary substantially depending on the type of alloy used) or to a temperature close to that ambient for an electrolytic bath.
- the furnace thus has heating and cooling means distributed in an arrangement so that several (range or cycle of) bearings and strip restoration temperature pipe (depending on its properties and grade of steel) and temperature adjustment required at the entrance of the coating unit (5) are ensured.
- the web then travels through the coating unit (5) such as by hot dipping in a hot liquid metal bath as a coating agent.
- Spinning, heating, cooling, water-bath dipping means are arranged downstream of the metal bath, then the strip is led to a second so-called intermediate accumulator, in order to adjust the speed of travel to a finishing section ( 6) which can successively comprise a second skin-pass, a tensioning planer, means for controlling the properties of the galvanized strip (by thickness measurement / surface inspection / etc.), a second optional final coating means (7). ) of surface passivation with a drying module.
- an outlet section (8) comprising an assembly (81) of modules such as an outlet accumulator, an optional shear beam shear bands, final surface inspection means, an optional oiling module, a band shear allowing the cross-section strips to divide and direct the web on at least one winder and ideally two winders (8a, 8b).
- modules such as an outlet accumulator, an optional shear beam shear bands, final surface inspection means, an optional oiling module, a band shear allowing the cross-section strips to divide and direct the web on at least one winder and ideally two winders (8a, 8b).
- Figure 2 illustrates as simply as possible the intended principle of strip restoration in the oven (4) of the installation according to the invention as described in figure 1 .
- the hardness (D) of the band (hardness increase is defined as hardening) is given as a function of the temperature T (° C) on the abscissa.
- the skin-pass imposes hardening by hardening and gives it a new state hardened (Ee) with higher hardness at the exit of the skin-pass (3).
- the object of the present invention is then to be able to reduce the hardness of the outgoing band of the skin-pass by a heating / cooling arrangement of the oven (4) for subjecting the band a thermal cycle in an interval and under at least a temperature level included in the hatched part (REST) of the figure 2 representing a possible range of tape restoration temperature.
- the curve shown thus very simply shows that the temperature rise from the hardened state (Ee) in the restoration range brings the band back to its state close to the initial hardened state (Ei), however without having to raise the temperature above those included in said domain (REST), that is, without having to go up to higher temperatures involving recrystallization commonly called annealing (represented by the RECR cross-hatching portion) of band or even a grain enlargement (as required by annealing following a cold rolling dedicated to a significant reduction in thickness).
- annealing represented by the RECR cross-hatching portion
- a grain enlargement as required by annealing following a cold rolling dedicated to a significant reduction in thickness
- Figure 3 presents a graph of temperature T (° C) as a function of time t (s) for three possible control settings of the restoration step referred to by figure 2 for example for three grades or three strip reduction conditions at the furnace inlet (4).
- a path of thermal control of the oven is thus controlled to optimize a temperature cycle applied to the strip moving in at least one chamber of the oven, in order to achieve a restoration phase of the material of the strip, depending on the external conditions and intrinsic of said band, then for the temperature of the band at the end of the restoration, particularly to minimize the duration of heating / active cooling (minimized energy request) for the restoration of the band.
- Dt_Rest the end of the restoration period
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Coating With Molten Metal (AREA)
Abstract
La présente invention décrit une installation de décapage et de revêtement métallique telle qu'une galvanisation d'une bande métallique en défilement continu, comprenant successivement selon le défilement au moins une unité de décapage, un four, une unité de revêtement, et pour laquelle la bande métallique entrante dans l'unité de décapage est par défaut un produit laminé à chaud. L'installation selon l'invention est caractérisée en ce que : - un laminoir à allongement/réduction limitée d'épaisseur de bande dit skin-pass est disposé entre l'unité de décapage et le four ; - le four impose à la bande un cycle thermique permettant de maitriser une restauration de structure de bande (c'est-à-dire libre de recristallisation de bande) et impose en sortie de four une mise à température de bande requise en entrée d'unité de revêtement métallique. Un procédé de décapage et de revêtement métallique est également proposé.The present invention describes a pickling and metal coating plant such as a galvanization of a metal strip in continuous scrolling, successively comprising, according to the scrolling, at least one pickling unit, an oven, a coating unit, and for which the incoming metal strip in the stripping unit is by default a hot rolled product. The installation according to the invention is characterized in that: - A laminator limited lengthening / reduction of the so-called skin-pass band thickness is disposed between the pickling unit and the furnace; the oven imposes on the strip a thermal cycle making it possible to control a restoration of the strip structure (that is to say free of tape recrystallization) and imposes at the outlet of the oven a required strip temperature at the inlet of the strip; metal coating unit. A pickling and metal coating process is also provided.
Description
La présente invention concerne une installation de décapage et de revêtement métallique d'une bande métallique selon le préambule de la revendication 1 ainsi qu'un procédé associé selon le préambule de la revendication 12.The present invention relates to a pickling and metal coating plant of a metal strip according to the preamble of
Jusqu'à maintenant, des lignes de laminages d'acier à chaud permettent de fournir des bandes métalliques d'une épaisseur généralement supérieure à environ 1,2mm. Ces lignes requièrent de façon classique, l'association d'une coulée continue délivrant des produits dont l'épaisseur voisine de 200 à 250 mm, nécessite le recours d'un ensemble de cages de laminoirs à chaud pour obtenir une forte réduction d'épaisseur en particulier lorsque l'on veut atteindre des épaisseurs minimales de environ 1mm. Le bilan énergétique et le dimensionnement de telles installations pour atteindre ce résultat sont relativement lourds. Récemment, de nouveaux procédés à coulée continue de métal chaud de type dit ESP (« Endless Strip Production ») permettent d'obtenir avec l'aide d'un ensemble plus réduit de cages de laminoir à chaud des bandes métalliques en acier d'une épaisseur minimale aux environs de 0,7 mm à ce jour. Il est fort probable que, dans les années ou décennies prochaines, des épaisseurs moindres par exemple aux environs de 0,5 mm seront technologiquement atteintes par de tels procédés sur l'exemple du type ESP. Il est aussi à noter que de tels procédés permettent aussi une production continue de bandes métalliques et sont donc très efficaces en termes de productivité. De plus, leur bilan énergétique pour transformer le produit depuis la coulée continue jusqu'à la fin du laminage de fine épaisseur est réduit par rapport aux procédés antérieurs. Généralement, les producteurs de telles bandes disposent donc d'au moins une ligne de coulée continue couplée à un ensemble de cages de laminage à chaud et en sortie à un système de bobineuses de bandes. Ces bandes sont ainsi livrées en bobines dites « à chaud » avec une surface oxydée, c'est-à-dire sous forme de bobines de bandes non décapées.Until now, hot-rolled steel lines make it possible to supply metal strips with a thickness generally greater than about 1.2 mm. These lines require conventionally, the combination of a continuous casting delivering products whose thickness of about 200 to 250 mm, requires the use of a set of hot mill stands to obtain a sharp reduction in thickness. especially when one wants to reach minimum thicknesses of about 1mm. The energy balance and the sizing of such facilities to achieve this result are relatively heavy. Recently, new hot metal continuous casting processes of the ESP (Endless Strip Production) type make it possible to obtain, with the aid of a smaller set of hot rolling mill stands, steel strips of minimum thickness around 0.7 mm to date. It is very likely that, in the coming years or decades, lesser thicknesses, for example around 0.5 mm, will be technologically attained by such processes on the example of the ESP type. It should also be noted that such methods also allow continuous production of metal strips and are therefore very efficient in terms of productivity. In addition, their energy balance to transform the product from continuous casting until the end of the thin-layer rolling is reduced compared to previous methods. Generally, producers of such Thus, the belts have at least one continuous casting line coupled to a set of hot rolling cages and at the output to a strip winder system. These strips are thus delivered in so-called "hot" coils with an oxidized surface, that is to say in the form of coils of non-stripped strips.
Dès lors, si une opération de revêtement métallique telle qu'une galvanisation de la bande « à chaud » devait être engagée, les bandes obtenues par les procédés « à chaud » décrits ci-dessus devraient être encore décapées, puis finalement galvanisées. L'épaisseur de sortie de ses bandes produites serait alors au moins supérieure généralement à 1,2mm avec les voies d'élaborations à chaud conventionnelles. De plus, pour obtenir des bandes métalliques revêtues, pour exemple galvanisées de plus faible épaisseur et aussi avec de bonnes propriétés d'emboutissage, il est nécessaire de laminer à froid ces bandes sous forte réduction d'épaisseur. Le laminage à froid induit ainsi un écrouissage de l'acier, par rapport à un niveau original faible dudit écrouissage, il offre cependant l'avantage de participer à l'obtention de bonnes propriétés finales d'emboutissage, mais oblige, en aval de l'opération de laminage, de recuire la bande métallique laminée, avant galvanisation, afin de permettre d'obtenir, en particulier, les bonnes propriétés d'emboutissage au final. Un exemple de ligne de galvanisation pour des bandes entrantes laminées à froid, recuites puis galvanisées est décrit par
A partir d'un procédé à chaud de production de bandes à faible épaisseur (quelques dixièmes de mm, par exemple 0,7mm), tel que le procédé de type ESP, ces épaisseurs faibles de bandes produites « à chaud » rejoignent progressivement un intervalle d'épaisseur significative produite par l'intermédiaire du laminage à froid décrit précédemment.From a low thickness hot strip production process (a few tenths of a millimeter, for example 0.7 mm), such as the ESP type process, these low thicknesses of "hot" stripes gradually join a significant thickness range produced by cold rolling previously described.
Une méthode pour décaper et galvaniser en continu des produits défilants (ou bobinés) et non décapés, issus d'un procédé à chaud a été décrite en 2001 dans
Dans le but de réduire l'épaisseur des produits décapés et galvanisés (issus en amont d'un produit à chaud non décapés) tout en s'affranchissant d'un laminage à froid puis d'un recuit, les fascicules de brevets apparentés
Un but de la présente invention est donc de proposer une solution d'élargir une gamme d'épaisseurs de produits sortants d'un procédé de revêtement métallique en continu alimenté par défaut par une bande d'acier non décapée en défilement, issues de bobines élaborées par un procédé à chaud. La solution proposée doit aussi assurer que la bande en entrée de l'unité de revêtement possède un taux minimal d'écrouissage, même si une réduction d'épaisseur de bande pour élargir la dite gamme, est effectuée. Enfin, cette solution doit permettre de s'affranchir d'une étape de réduction d'épaisseur élevée par laminage à froid impliquant une étape de recuit de la bande (recristallisation), tout en permettant cependant de conserver de bonnes qualités d'emboutissage du produit final.An object of the present invention is therefore to propose a solution to widen a range of thicknesses of outgoing products of a continuous metal coating process fed by default by a non-stripped steel strip in scrolling, coils developed by a hot process. The proposed solution must also ensure that the input web of the coating unit has a minimum rate of work hardening, even if a reduction in web thickness to expand said range, is performed. Finally, this solution must make it possible to dispense with a step of reduction of high thickness by cold rolling involving a step of annealing the strip (recrystallization), while still allowing to maintain good qualities of stamping of the product. final.
Egalement, la présente invention doit permettre d'assurer un procédé combiné continu d'étapes conjuguant le décapage, la réduction d'épaisseur, l'amélioration de rugosité et planéité, le maintien des propriétés optimales du matériau après la réduction d'épaisseur, et le dépôt du revêtement métallique. Le revêtement métallique est principalement une galvanisation sur la bande comme par exemple par un procédé de trempé à chaud dans un bain de métal liquide comprenant divers type d'alliages métalliques pour une protection galvanique de l'acier, suivi de traitements associés pour assurer la qualité de marché des produits revêtus. Il est aussi possible de prévoir tout autre procédé de revêtement métallique, tel qu'une galvanisation dans un bain électrolytique approprié.Also, the present invention must provide a continuous combined process of steps combining pickling, thickness reduction, improvement of roughness and flatness, maintenance of the optimum properties of the material after the thickness reduction, and the deposition of the metal coating. The metal coating is mainly a galvanization on the strip such as for example by a method of hot dipping in a bath of liquid metal comprising various types of metal alloys for galvanic protection of the steel, followed by associated treatments to ensure the quality market for coated products. It is also possible to provide any other method of metal coating, such as galvanizing in a suitable electrolytic bath.
Une solution sous forme d'installation est ainsi proposée au travers des caractéristiques de la revendication 1. Enfin, un procédé associé est également proposé au travers des caractéristiques de la revendication 12.A solution in the form of an installation is thus proposed through the features of
A partir d'une installation de décapage et de revêtement métallique telle qu'une galvanisation d'une bande métallique en défilement continu, comprenant successivement selon le défilement au moins une unité de décapage, un four, une unité de revêtement (comme un bain de métal liquide comme agent de revêtement ou un bain électrolytique), et pour laquelle la bande métallique entrante dans l'unité de décapage est par défaut un produit laminé à chaud,
l'installation selon l'invention est caractérisée en ce que :
- un laminoir à allongement/réduction limitée d'épaisseur de bande dit skin-pass est disposé entre l'unité de décapage et le four ;
- le four impose à la bande un cycle thermique permettant de maitriser une restauration de structure de bande (c'est-à-dire libre de recristallisation de bande) et impose en sortie de four une mise à température de bande requise en entrée d'unité de revêtement métallique (par des moyens de chauffage ou de refroidissement adéquats).
the installation according to the invention is characterized in that:
- a skin-pass-band limited lengthening / reducing mill is disposed between the pickling unit and the oven;
- the oven imposes on the strip a thermal cycle making it possible to control a strip structure restoration (that is to say free of tape recrystallization) and imposes at the outlet of the furnace a required strip temperature rise at the unit inlet metal coating (by suitable heating or cooling means).
Ainsi, il est assuré au travers d'une association de procédés continus de réduction limitée et, en aval, de contrôle de température, la production d'un produit (bande) galvanisé pour laquelle le produit entrant dans l'installation peut être une série de bobines métalliques non décapées issues d'un procédé d'élaboration à chaud qui peut avoir une épaisseur supérieure en entrée par rapport à l'épaisseur finale après revêtement. Le couplage de ces procédés permet ainsi de maintenir ou d'améliorer les propriétés de la bande entrante, sachant que, même si une réduction est faiblement appliquée par le skin-pass, le four impose un intervalle de température à la bande sous un mode de restauration, sans besoin d'imposer un mode de recristallisation, voire de grossissement de grains métallique tel qu'une phase de recuit le requiert après un laminage à froid.Thus, it is ensured through a combination of continuous processes of limited reduction and, downstream, of temperature control, the production of a product (strip) galvanized for which the product entering the installation can be a series non-pickled metal coils from a hot forming process which may have a greater thickness at the inlet relative to the final thickness after coating. The coupling of these methods thus makes it possible to maintain or improve the properties of the incoming band, knowing that, even if a reduction is weakly applied by the skin-pass, the oven imposes a temperature interval on the strip in a mode of restoration, without the need to impose a recrystallization mode, or even magnification of metal grains such as an annealing phase requires after cold rolling.
En effet, à l'inverse d'un laminage à froid classique (forte réduction d'épaisseur) exigeant un recuit (par au moins une recristallisation) à très haute température (par exemple 750°C ou plus), le four sous atmosphère généralement non oxydante, selon l'invention impose une unique restauration de bande sous un palier de plus faibles températures (entre 300°C et 700°C pendant moins de deux minutes) après que la bande ait subi une réduction faible d'épaisseur dans le skin-pass. Ainsi, l'installation permet avantageusement un équilibrage entre les effets de réduction (limitée) d'épaisseur sur une plus grande gamme et la garantie d'une maitrise de restauration possible de bande afin de garantir de hautes qualités d'emboutissage de bande sortante (effet d'écrouissage minimisé par restauration). Enfin, la réduction limitée par skin-pass permet d'assurer une rugosité et une planéité adaptée à une meilleure mouillabilité nécessaire pour le revêtement en aval et un meilleur essorage en aval. Une unité de nettoyage installée en aval du skin pass permettra en outre d'évacuer d'éventuelles émulsions/détergents ou autres produits alcalins, ainsi que poussières (fine de fer) et autres débris métalliques possiblement générés par l'action du skin-pass, ceci afin d'améliorer la qualité du revêtement.Indeed, unlike a conventional cold rolling (sharp reduction in thickness) requiring annealing (by at least one recrystallization) at a very high temperature (for example 750 ° C or more), the furnace under atmosphere generally non-oxidizing, according to the invention imposes a single strip restoration under a lower temperature step (between 300 ° C and 700 ° C for less than two minutes) after the band suffered a slight reduction in thickness in the skin-pass. Thus, the installation advantageously allows balancing between the effects of (limited) thickness reduction over a larger range and the guarantee of a mastery of possible strip restoration in order to guarantee high qualities of outgoing strip stamping ( minimized work hardening effect by restoration). Finally, the limited reduction by skin-pass makes it possible to ensure a roughness and a flatness adapted to a better wettability necessary for the coating downstream and a better spinning downstream. A cleaning unit installed downstream of the skin pass will also remove any emulsions / detergents or other alkaline products, as well as dust (fine iron) and other metal debris possibly generated by the action of the skin pass, this is to improve the quality of the coating.
Sachant qu'une réduction du produit entrant dans l'installation selon l'invention est réalisable, il est ainsi possible de produire des bandes sortant plus minces, et donc d'augmenter les capacités de production et la gamme d'épaisseur (minimisable) sur une ligne continue combinée de décapage et revêtement métallique par exemple par galvanisation. La qualité d'emboutissage de bande sortante est aussi améliorée. Pour exemple, pour certains produits en particulier de relative faible épaisseur d'entrés particulièrement entre 0,5 mm à au moins 5 mm d'épaisseur, le skin-pass ne procède qu'à un faible allongement (ou réduction d'épaisseur) et permet cependant d'obtenir une bande galvanisée disposant en particulier d'excellentes propriétés d'emboutissage.Knowing that a reduction of the product entering the installation according to the invention is feasible, it is thus possible to produce thinner outgoing strips, and therefore to increase the production capacities and the thickness range (minimizable) on a combined continuous line of pickling and metal coating for example by galvanizing. The outgoing stamping quality is also improved. For example, for certain products in particular of relatively small thickness of entrances, particularly between 0.5 mm and at least 5 mm thick, the skin-pass only proceeds with a small elongation (or reduction in thickness) and However, it provides a galvanized strip having in particular excellent stamping properties.
Parallèlement en association avec l'installation selon l'invention proposée précédemment ainsi que de tous les aspects et modes de réalisation s'y référant dans ce document, l'invention propose un procédé de décapage et de revêtement métallique d'une bande métallique en défilement continu, comprenant successivement selon le défilement au moins une étape de décapage (2), une étape de traitement thermique en contrôle de température de bande (4), une étape de revêtement telle qu'une galvanisation (5) (comme par un trempé dans un bain de métal liquide ou dans un bain électrolytique), et pour laquelle la bande métallique en amont de l'étape de décapage est par défaut un produit laminé à chaud,
le dit procédé étant caractérisé en ce que :
- une étape de réduction limitée d'épaisseur, de modification de rugosité et planéité de bande est activable entre l'étape de décapage et l'étape de contrôle de température de bande;
- en cas d'étape activée de réduction limitée d'épaisseur, de modification de rugosité et planéité, l'étape de contrôle de température de bande impose à la bande un cycle thermique permettant de maitriser une restauration de structure de bande libre de recristallisation de bande et impose à la bande une mise sous température de sortie de bande requise en entrée dans l'unité de revêtement métallique.
said process being characterized in that:
- a step of limited thickness reduction, roughness modification and band flatness is activatable between the stripping step and the tape temperature control step;
- in the case of an activated step of limited thickness reduction, roughness modification and flatness, the strip temperature control step imposes on the strip a thermal cycle making it possible to control a band free recrystallization strip structure restoration. and imposes on the strip a required strip outlet temperature setting input into the metal coating unit.
Une étape post revêtement est aussi prévue pour des opérations possibles simples ou conjuguées au moyen d'un skin-pass complémentaire et d'une planeuse sous traction, ladite opération étant suivie d'une étape de revêtement complémentaire (telle qu'une étape de passivation).A post-coating step is also provided for simple or combined operations by means of a complementary skin-pass and a tensioning machine, said operation being followed by a complementary coating step (such as a passivation step). ).
Un ensemble de sous-revendications présente également des avantages de l'invention.A set of subclaims also has advantages of the invention.
Des exemples de réalisation et d'application sont fournis à l'aide de figures décrites :
- Figure 1
- Exemple de mode de réalisation d'une installation selon l'invention,
- Figure 2
- Principe de restauration de bande dans le four de l'installation selon l'invention,
- Figure 3
- Paramétrages de contrôle de l'étape de restauration.
- Figure 1
- Example of an embodiment of an installation according to the invention,
- Figure 2
- Principle of strip restoration in the furnace of the installation according to the invention,
- Figure 3
- Control settings of the restore step.
l'installation caractérisé en ce que
- un laminoir à allongement/réduction limitée d'épaisseur de bande dit skin-pass (3) est disposé entre l'unité de décapage et le four ;
- le four dispose de moyens thermiques aptes à imposer à la bande un cycle thermique permettant au moins de maitriser une restauration de structure de bande libre de recristallisation de bande et à imposer en sortie de four une mise à température de bande requise en entrée d'unité de revêtement métallique.
the installation characterized in that
- a skin-band limited lengthening / reducing mill (3) is disposed between the pickling unit and the furnace;
- the furnace has thermal means capable of imposing on the strip a thermal cycle allowing at least to master a strip band recrystallization free band structure restoration and to impose at the outlet of the furnace a required strip temperature rise at the unit inlet of metal coating.
Le cycle thermique a pour effet de permettre :
- Une chauffe de bande jusqu'à une plage de restauration sous une gamme contrôlable de température la plus large possible (par exemple 300-700°C)
- Un maintien pendant une durée minimale de restauration de bande (qui dépend de la température ci-dessus et des conditions de réduction d'épaisseur, ainsi que de la chimie requise par les propriétés métallurgiques du grade de la bande)
- Un ajustement final de la température par chauffe ou refroidissement en fin de cycle pour atteindre la température requise pour le revêtement.
- Strip heating up to a range of restoration under a controllable range of temperature as wide as possible (eg 300-700 ° C)
- Maintain for a minimum tape restoration time (which depends on the above temperature and thickness reduction conditions, as well as the chemistry required by the metallurgical properties of the grade of the tape)
- A final adjustment of the temperature by heating or cooling at the end of the cycle to reach the temperature required for the coating.
En amont de l'unité de décapage (2), une section d'entrée (1) permet l'introduction de la bande dans la dite unité au moyen de deux débobineuses (1a, 1b) déroulant successivement les bobines vers une cisaille de bandes et une soudeuse (11) afin de souder têtes et queues de deux bandes successives, ainsi qu'un accumulateur (non représenté) pour adapter la vitesse de défilement de bande lors d'un soudage, puis pour l'introduction des bandes soudées dans l'unité de décapage (2). Un moyen de décalaminage (« Brise oxyde ») est aussi disposé avant l'entrée de bande dans l'unité de décapage (2).Upstream of the stripping unit (2), an inlet section (1) allows the introduction of the strip into said unit by means of two uncoiling machines (1a, 1b) successively pulling the coils towards a strip shear and a welder (11) for welding heads and tails of two successive strips, as well as an accumulator (not shown) for adapting the tape running speed during a welding, and then for introducing the welded webs into the web. pickling unit (2). A descaling means ("oxide breeze") is also disposed prior to web entry into the pickling unit (2).
L'unité de décapage (2) peut comprendre des bains acides successivement juxtaposés, ainsi que des moyens de rinçage et de séchage. Elle peut alternativement comprendre un système de projection sur le produit d'un composé décapant tel qu'au moyen d'un matériau solide abrasif et, si besoin, un liquide. Le matériau solide abrasif comprend par exemple des particules et/ou grains solides et le liquide, si besoin, comprend au moins de l'eau. Enfin pour rappel, la bande métallique entrante dans l'unité de décapage est par défaut un produit laminé à chaud, présentant une épaisseur minimale de quelques dixièmes de millimètres. Alternativement, la bande métallique en amont de l'unité de décapage pourrait aussi être un produit laminé à froid remplaçant le produit laminé à chaud, auquel cas la bande n'est pas décapée dans l'unité de décapage (ou déviée de l'unité de décapage vers le skin-pass) et le four prévoit des moyens de chauffage et de refroidissement supplémentaires pour assurer un recuit de bande. Cette alternative n'est toutefois pas décrite plus dans le cadre de l'invention, car même si elle présente une flexibilité de commutation entre des bandes « à chaud » ou « à froid » à revêtir en surface par exemple pour les galvaniser, elle requiert soit que le four permette à nouveau un recuit, soit qu'il soit accepté de conserver des valeurs élevées de dureté du à l'écrouissage par laminage à froid.The pickling unit (2) may comprise successively juxtaposed acid baths, as well as rinsing and drying means. It may alternatively comprise a projection system on the product of a stripping compound such as by means of an abrasive solid material and, if necessary, a liquid. The abrasive solid material comprises for example particles and / or solid grains and the liquid, if necessary, comprises at least water. Finally, as a reminder, the metal strip entering the stripping unit is by default a hot-rolled product having a minimum thickness of a few tenths of a millimeter. Alternatively, the metal strip upstream of the pickling unit could also be a cold rolled product replacing the hot rolled product, in which case the strip is not pickled in the stripping unit (or deviated from the unit). stripping to the skin-pass) and the furnace provides additional heating and cooling means for band annealing. However, this alternative is not described further in the context of the invention, because even if it has a flexibility of switching between "hot" or "cold" strips to be coated surface for example to galvanize them, it requires that the oven allows again an annealing, either that it is accepted to maintain high values of hardness due to cold rolling work hardening.
L'installation selon l'invention prévoit que le skin-pass (3) disposé en sortie de l'unité de décapage (2) permette un facteur de réduction d'épaisseur de 0,1% à au moins 30%. La sortie du skin-pass est couplée à une unité de nettoyage (31) de la bande comprenant au moins un des moyens de nettoyage parmi un dégraissage (si le taux de réduction supérieur à environ 10% qui nécessiterait l'utilisation d'émulsion de type huile-eau lors du laminage dans skin-pass), un brossage, un arrosage, un essorage, un séchage. Enfin, le skin-pass utilise des cylindres de travail à rugosité définie adaptée au degré de rugosité souhaité sur la bande après opérations des cylindres, afin d'assurer au mieux l'adhérence du revêtement ultérieur sur la bande. Le type de skin-pass installé peut être monocage voire comprendre deux cages juxtaposées.The installation according to the invention provides that the skin-pass (3) disposed at the outlet of the pickling unit (2) allows a thickness reduction factor of 0.1% to at least 30%. The output of the skin-pass is coupled to a cleaning unit (31) of the strip comprising at least one of the cleaning means among a degreasing (if the reduction rate greater than about 10% which would require the use of emulsion of oil-water type when rolling in skin-pass), brushing, watering, spinning, drying. Finally, the skin-pass uses working cylinders with defined roughness adapted to the desired degree of roughness on the strip after operations of the rolls, to ensure the best adhesion of the subsequent coating on the strip. The type of skin-pass installed can be monocage even include two juxtaposed cages.
En sortie de l'unité de nettoyage, la bande entre ainsi dans le four (4) comprenant successivement au moins un des moyens de chauffage parmi des inducteurs ou autres moyens de réchauffage, des tubes radiants ou autres moyens de maintien de température, au moins une zone supplémentaire de moyens de réchauffage rapide et/ou de refroidissement rapide. Ces moyens de chauffage peuvent présenter des dynamiques diverses de chauffe ou de refroidissement de la bande en fonction des exigences du traitement thermique selon l'invention. Le four est idéalement mis sous atmosphère non oxydante. Afin d'assurer la restauration de bande, une section du four comprend des moyens de chauffage de la bande assurant un maintien de température de bande sous une température seuil de recristallisation au moins partielle de la bande, idéalement sous un palier contrôlable de température entre 300°C et 700°C pendant moins de deux minutes.At the outlet of the cleaning unit, the strip thus enters the furnace (4) successively comprising at least one of the heating means among inductors or other heating means, radiant tubes or other means for maintaining temperature, at least an additional area of rapid heating means and / or rapid cooling. These heating means may have various dynamics of heating or cooling the band according to the requirements of the heat treatment according to the invention. The oven is ideally placed under a non-oxidizing atmosphere. In order to ensure strip restoration, a section of the furnace comprises means for heating the strip ensuring a maintenance of the strip temperature under a threshold temperature of at least partial recrystallization of the strip, ideally under a controllable temperature plateau between 300 ° C. ° C and 700 ° C for less than two minutes.
Si le palier de température de restauration est inférieur à la température requise en entrée de l'unité de revêtement, le four peut enfin élever la température de sortie de bande requise avant entrée dans l'unité de revêtement métallique par trempé à chaud autour de 500°C pour une galvanisation classique, puis la fait redescendre au-dessous de cette valeur, idéalement vers 465°C pour un bain liquide de galvanisation (cette température pouvant varier sensiblement suivant le type d'alliage utilisé) ou vers une température proche de celle ambiante pour un bain électrolytique. Le four possède donc des moyens de chauffage et de refroidissement distribués selon une disposition de sorte que plusieurs (gamme ou cycle de) paliers et conduite de température de restauration de bande (selon ses propriétés et grade d'acier) et un ajustement à la température requise en entrée de l'unité de revêtement (5) soient assurés.If the restoration temperature step is less than the required temperature at the inlet of the coating unit, the oven can finally raise the required strip outlet temperature before entering the metal coating unit by hot dipping around 500 ° C for conventional galvanizing, and then to fall below this value, ideally towards 465 ° C for a liquid bath of galvanization (this temperature may vary substantially depending on the type of alloy used) or to a temperature close to that ambient for an electrolytic bath. The furnace thus has heating and cooling means distributed in an arrangement so that several (range or cycle of) bearings and strip restoration temperature pipe (depending on its properties and grade of steel) and temperature adjustment required at the entrance of the coating unit (5) are ensured.
La bande défile ensuite dans l'unité de revêtement (5) tel que par trempé à chaud dans un bain de métal liquide chaud comme agent de revêtement. Des moyens d'essorage, chauffage, refroidissement, trempage dans bac d'eau sont disposés en aval du bain métallique, puis la bande est conduite vers un second accumulateur dit intermédiaire, afin d'ajuster la vitesse de défilement vers une section de finition (6) pouvant comprendre successivement un second skin-pass, une planeuse sous tension, des moyens de contrôle des propriétés de la bande galvanisée (par mesure d'épaisseur/inspection de surface/etc.), un second moyen optionnel de revêtement final (7) de passivation en surface avec un module de séchage.The web then travels through the coating unit (5) such as by hot dipping in a hot liquid metal bath as a coating agent. Spinning, heating, cooling, water-bath dipping means are arranged downstream of the metal bath, then the strip is led to a second so-called intermediate accumulator, in order to adjust the speed of travel to a finishing section ( 6) which can successively comprise a second skin-pass, a tensioning planer, means for controlling the properties of the galvanized strip (by thickness measurement / surface inspection / etc.), a second optional final coating means (7). ) of surface passivation with a drying module.
Finalement, la bande sortant des sections de finition (6) et de revêtement final (7) entre dans une section de sortie (8) comprenant un ensemble (81) de modules tel qu'un accumulateur de sortie, une cisaille optionnelle de rives de bandes, des moyens finaux d'inspection de surface, un module optionnel de huilage, une cisaille de bandes permettant la coupe transversale de bandes afin de diviser et diriger la bande sur au moins une bobineuse et idéalement deux bobineuses (8a, 8b).Finally, the strip emerging from the finishing sections (6) and the final coating section (7) enters an outlet section (8) comprising an assembly (81) of modules such as an outlet accumulator, an optional shear beam shear bands, final surface inspection means, an optional oiling module, a band shear allowing the cross-section strips to divide and direct the web on at least one winder and ideally two winders (8a, 8b).
Cet exemple de mode de réalisation de l'installation selon l'invention permet ainsi la mise en oeuvre d'un procédé avantageux de décapage et de revêtement métallique d'une bande métallique en défilement continu, comprenant successivement selon le défilement au moins une étape de décapage (2), une étape de contrôle de température de bande (4), une étape de revêtement métallique (5), et pour laquelle la bande métallique en amont de l'étape de décapage est par défaut un produit laminé à chaud,
le dit procédé étant caractérisé en ce que :
- une étape de réduction d'épaisseur de la bande, de modification de rugosité et planéité de bande est activable entre l'étape de décapage et l'étape de contrôle de température de bande;
- en cas d'étape activée de réduction d'épaisseur, de modification de rugosité et planéité de bande, l'étape de contrôle de température de bande impose à la bande un cycle thermique permettant de maitriser une restauration de structure de bande libre de recristallisation de bande et impose à la bande une mise sous température de sortie de bande requise en entrée dans l'unité de revêtement métallique.
said process being characterized in that:
- a tape thickness reduction, roughness modification and tape flatness step is activatable between the etching step and the tape temperature control step;
- in the case of an activated step of thickness reduction, roughness modification and strip flatness, the strip temperature control step imposes on the strip a thermal cycle making it possible to control a free recrystallization strip structure restoration. band and imposes on the band a required strip outlet temperature setting input into the metal coating unit.
Claims (12)
caractérisé en ce que
characterized in that
caractérisé en ce que :
characterized in that
Priority Applications (9)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP14290086.9A EP2927343A1 (en) | 2014-03-31 | 2014-03-31 | Installation and method for pickling and metal coating of a metal strip |
MX2016012711A MX2016012711A (en) | 2014-03-31 | 2015-01-26 | Equipment and process for the pickling and metallic coating of a metal strip. |
EP15703485.1A EP3126539B1 (en) | 2014-03-31 | 2015-01-26 | Installation and method for pickling and metal coating of a metal strip |
PL15703485T PL3126539T3 (en) | 2014-03-31 | 2015-01-26 | Installation and method for pickling and metal coating of a metal strip |
ES15703485T ES2856229T3 (en) | 2014-03-31 | 2015-01-26 | Installation and procedure of stripping and metallic coating of a metallic strip |
RU2016138425A RU2016138425A (en) | 2014-03-31 | 2015-01-26 | INSTALLATION AND METHOD OF ETCHING AND APPLICATION OF METAL COATING ON THE METAL STRIP |
CN201580017944.2A CN106460136A (en) | 2014-03-31 | 2015-01-26 | Equipment and process for the pickling and metallic coating of a metal strip |
CN202111184286.XA CN113846281A (en) | 2014-03-31 | 2015-01-26 | Device and method for pickling and coating metal strips |
PCT/EP2015/051427 WO2015149960A1 (en) | 2014-03-31 | 2015-01-26 | Equipment and process for the pickling and metallic coating of a metal strip |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP14290086.9A EP2927343A1 (en) | 2014-03-31 | 2014-03-31 | Installation and method for pickling and metal coating of a metal strip |
Publications (1)
Publication Number | Publication Date |
---|---|
EP2927343A1 true EP2927343A1 (en) | 2015-10-07 |
Family
ID=50479152
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP14290086.9A Withdrawn EP2927343A1 (en) | 2014-03-31 | 2014-03-31 | Installation and method for pickling and metal coating of a metal strip |
Country Status (1)
Country | Link |
---|---|
EP (1) | EP2927343A1 (en) |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4436292A (en) | 1981-02-24 | 1984-03-13 | Sms Schloemann-Siemag Ag | System for the treatment of a continuous metal web |
JPH06285505A (en) * | 1993-03-31 | 1994-10-11 | Nisshin Steel Co Ltd | Manufacture of hot rolled band steel for hot dipping |
JPH07126747A (en) * | 1993-11-05 | 1995-05-16 | Sumitomo Metal Ind Ltd | Production of si-containing steel plate excellent in hot dip galvanizing suitability |
JPH08144036A (en) * | 1994-11-21 | 1996-06-04 | Sumitomo Metal Ind Ltd | Production of galvanized steel sheet by using hot rolled steel sheet as base metal |
WO2000003816A1 (en) * | 1998-07-17 | 2000-01-27 | Kawasaki Jukogyo Kabushiki Kaisha | Equipment and method for continuous plating of steel sheet |
US6761936B1 (en) | 1999-08-06 | 2004-07-13 | Sms Demag Ag | Method and installation for hot dip galvanizing hot rolled steel strip |
EP1861517B1 (en) | 2005-03-18 | 2008-12-31 | SMS Demag Aktiengesellschaft | Controlled thickness reduction in hot-dip coated hot-rolled steel strip and installation used therefor |
JP2010196146A (en) * | 2009-02-27 | 2010-09-09 | Nippon Steel Corp | Method for producing hot dip galvannealed steel sheet having excellent workability |
-
2014
- 2014-03-31 EP EP14290086.9A patent/EP2927343A1/en not_active Withdrawn
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4436292A (en) | 1981-02-24 | 1984-03-13 | Sms Schloemann-Siemag Ag | System for the treatment of a continuous metal web |
JPH06285505A (en) * | 1993-03-31 | 1994-10-11 | Nisshin Steel Co Ltd | Manufacture of hot rolled band steel for hot dipping |
JPH07126747A (en) * | 1993-11-05 | 1995-05-16 | Sumitomo Metal Ind Ltd | Production of si-containing steel plate excellent in hot dip galvanizing suitability |
JPH08144036A (en) * | 1994-11-21 | 1996-06-04 | Sumitomo Metal Ind Ltd | Production of galvanized steel sheet by using hot rolled steel sheet as base metal |
WO2000003816A1 (en) * | 1998-07-17 | 2000-01-27 | Kawasaki Jukogyo Kabushiki Kaisha | Equipment and method for continuous plating of steel sheet |
US6761936B1 (en) | 1999-08-06 | 2004-07-13 | Sms Demag Ag | Method and installation for hot dip galvanizing hot rolled steel strip |
EP1861517B1 (en) | 2005-03-18 | 2008-12-31 | SMS Demag Aktiengesellschaft | Controlled thickness reduction in hot-dip coated hot-rolled steel strip and installation used therefor |
US8163348B2 (en) | 2005-03-18 | 2012-04-24 | Sms Siemag Aktiengesellschaft | Controlled thickness reduction for hot-dip coated, hot-rolled steel strip and installation used in this process |
JP2010196146A (en) * | 2009-02-27 | 2010-09-09 | Nippon Steel Corp | Method for producing hot dip galvannealed steel sheet having excellent workability |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP1058588B1 (en) | Installation for making cold-rolled stainless steel bands | |
CA2385685C (en) | Method for making carbon steel bands, in particular packaging steel bands, and resulting bands | |
EP0769333A1 (en) | Method for continuously producing, in a line, rolled sheet metal strip of stainless steel with improved surface condition | |
EP3126539B1 (en) | Installation and method for pickling and metal coating of a metal strip | |
JP5839180B2 (en) | Method for cooling hot-rolled steel sheet | |
EP2927343A1 (en) | Installation and method for pickling and metal coating of a metal strip | |
JP2007002297A (en) | Method for hot-dip metal plating electric resistance welded steel pipe | |
JP2965969B1 (en) | Continuous plating method for steel sheet | |
EP2958687B1 (en) | Method for rolling a metal strip | |
CA1107179A (en) | Method for making a hard steel elongated element | |
EP0126696B1 (en) | Method for continuously producing an overaged steel strip coated with zinc or an aluminium-zinc alloy | |
EP1061139B1 (en) | Method of manufacturing deep drawing steel sheets by direct casting of thin strips | |
EP1100632B1 (en) | Method for the continuous production of a metal strip | |
JP5386772B2 (en) | Method for producing alloyed hot-dip galvanized steel strip | |
FR2942978A1 (en) | Stainless steel strip producing method, involves annealing hard strip, subjecting annealed strip to pickling for removing carbon deposit, and subjecting strip to skin pass type superficial cold rolling | |
EP0245174A1 (en) | Process for producing a polymetallic composite web, especially a thin one based on steel, and articles obtained starting from such a web | |
EP0111039A1 (en) | Process for the high speed continuous galvanizing and annealing of a metallic wire | |
FR2513548A1 (en) | HOT ROLLED METHOD OF STRIP AND HOT ROLLED FOR STRIPS | |
FR2671809A1 (en) | CONTINUOUS GALVANIZATION PROCESS AT HIGH TEMPERATURE. | |
JPH10130801A (en) | Production of hot-dip plated steel sheet excellent in surface quality | |
EP0870069A1 (en) | Method for galvanising a steel sheet containing oxidizable alloying elements | |
FR2689909A1 (en) | Prodn. of finished galvanised metal products - in an integrated galvanising and drawing installation | |
EP2173918B1 (en) | Equipment for coating a metal strip | |
JP2003253413A (en) | Facility and method for manufacturing both cold rolled steel plate and plated steel plate | |
JPH0971850A (en) | Production of hot dip coated steel sheet having excellent surface quality |
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): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
17P | Request for examination filed |
Effective date: 20160407 |
|
RBV | Designated contracting states (corrected) |
Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 20160408 |