EP4143494A1 - Verfahren zum nachrüsten einer wärmebehandlungsanlage - Google Patents
Verfahren zum nachrüsten einer wärmebehandlungsanlageInfo
- Publication number
- EP4143494A1 EP4143494A1 EP21718843.2A EP21718843A EP4143494A1 EP 4143494 A1 EP4143494 A1 EP 4143494A1 EP 21718843 A EP21718843 A EP 21718843A EP 4143494 A1 EP4143494 A1 EP 4143494A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- furnace
- component
- control station
- temperature control
- heat treatment
- 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.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
- F27B9/02—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity of multiple-track type; of multiple-chamber type; Combinations of furnaces
- F27B9/029—Multicellular type furnaces constructed with add-on modules
-
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/62—Quenching devices
- C21D1/673—Quenching devices for die quenching
-
- 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
- C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
-
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0056—Furnaces through which the charge is moved in a horizontal straight path
-
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0068—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
-
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
-
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
- C21D9/48—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals deep-drawing sheets
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
- F27B9/02—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity of multiple-track type; of multiple-chamber type; Combinations of furnaces
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
- F27B9/02—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity of multiple-track type; of multiple-chamber type; Combinations of furnaces
- F27B9/028—Multi-chamber type furnaces
Definitions
- the invention relates to a method for retrofitting a
- the invention can be used in particular for retrofitting existing press hardening lines in which a press hardening tool is arranged downstream of a continuous furnace, in particular a roller hearth furnace.
- the retrofitted heat treatment line advantageously allows partial heat treatment of metallic components if necessary.
- press hardening Established heat treatment process known as “press hardening”.
- the sheet steel which is regularly provided in the form of a blank, is first heated in an oven and then cooled in a press during the formation of the sheet and thereby hardened.
- the upper and lower end areas of the B-pillar should have a comparatively low strength, on the one hand to be able to absorb deformation energy during a side impact and on the other hand during a side impact the assembly of the B-pillar to enable easy connectivity with other body components.
- the hardened component In order to form such a partially hardened body component, it is necessary for the hardened component to have different strength properties in the subregions.
- the tempering station is provided and set up to set different temperatures in the subareas of the component, which is initially uniformly heated, so that different strength properties are set in the subareas during the subsequent press hardening.
- Optimal cycle times which play an important role in the automotive industry in particular, can be achieved if the components oven, temperature control station and press hardening tool are arranged "in line", i.e. directly behind one another.
- a method for retrofitting a heat treatment system is to be specified that allows both a partially different heat treatment of a metallic component that can be carried out as efficiently as possible on an industrial scale and, in particular, the most efficient possible implementation of a conventional press hardening process.
- a method for retrofitting a heat treatment plant has at least the following steps: a) dividing a continuous furnace into a first furnace and a second furnace, b) arranging a temperature control station in the heat treatment plant, the temperature control station being arranged downstream of the first furnace and upstream of the second furnace and wherein the temperature control station is provided and set up to set a temperature difference between at least one first sub-area and at least one second sub-area of a metallic component to be treated, c) Adapting a mode of operation of the heat treatment plant.
- the proposed method is preferably used to retrofit a heat treatment system or heat treatment line with a continuous furnace and a press hardening tool.
- the press hardening tool is located downstream of the continuous furnace (to be retrofitted).
- the press hardening tool is in particular provided and set up to reshape the component at the same time or at least partially in parallel and (at least partially) to quench it.
- the continuous furnace can be a roller hearth furnace.
- the heat treatment system to be retrofitted and / or the retrofitted heat treatment system preferably have an arrangement “in line”.
- the continuous furnace and the press hardening tool of the heat treatment system to be retrofitted or the first furnace, the tempering station, the second furnace and the press hardening tool (in the order mentioned) are preferably arranged directly one behind the other.
- the metallic component (to be treated by means of the heat treatment system) is preferably a metallic blank, a sheet steel or an at least partially preformed semi-finished product.
- the metallic component is preferably made with or made of a (hardenable) steel, for example a boron (manganese) steel, e.g. B. with the designation 22MnB5 formed.
- the metallic component is at least for the most part provided with a (metallic) coating or is precoated.
- the metallic coating can be, for example, a (primarily) zinc-containing coating or (primarily) aluminum and / or silicon containing coating, in particular a so-called aluminum / silicon (Al / Si) coating act.
- an (existing) continuous furnace in particular a roller hearth furnace, is divided into a first furnace and a second furnace.
- the dividing is preferably carried out in such a way that the first furnace and the second furnace each form a continuous furnace, in particular a roller hearth furnace.
- the dividing can take place in such a way that the first furnace forms a continuous furnace and the second furnace a chamber furnace.
- the dividing can be done by mechanical and / or thermal cutting.
- a region of the continuous furnace be removed in step a). This is done in particular in such a way that a free space is formed for the temperature control station (in the continuous furnace).
- a temperature control station is arranged in the heat treatment system, the temperature control station being arranged (directly) after the first furnace and (directly) in front of the second furnace.
- the temperature control station is provided and set up to set a temperature difference between at least one first sub-area and at least one second sub-area of a metallic component to be treated (by means of the heat treatment system).
- the temperature control station can have one or more nozzles which are provided and set up for discharging a (cooling) fluid to the at least one first partial area of the component.
- the temperature control station is arranged between the first oven and the second oven.
- the temperature control station is preferably arranged in such a way that the first furnace, the temperature control station and the second furnace (in the order mentioned) in particular are placed directly behind one another. “Immediately one behind the other” here means in particular that no further components used for heat treatment are provided between the temperature control station and the corresponding furnace. However, a (minimum) distance of at least 0.5 m [meters] can be provided between the temperature control station and the first furnace and / or the second furnace. In other words, it is preferred that in step b) the temperature control station is arranged in line with the first oven and the second oven. In step c) there is an adaptation of an operating mode of the
- Heat treatment plant If several operating modes are provided for the heat treatment system to be retrofitted, one or more of the operating modes or even all operating modes of the heat treatment system can be adapted or changed in step c).
- step c) the mode of operation of the heat treatment system is adapted in such a way that a passage speed through the first furnace is reduced compared to a passage speed through the continuous furnace, in particular if partial heat treatment, in particular Hardening, is exercised or the (retrofitted) heat treatment system is operated in a first operating mode in which a temperature difference between a first sub-area and a second sub-area of the component is set in at least one metallic component by means of the temperature control station.
- the speed of passage through the first furnace is preferably reduced to a speed in the range from 0.01 to 1 m / s [meters per second], in particular in the range from 0.08 to 0.3 m / s.
- the reduced throughput speed which is preferably set when partial heat treatment is carried out by means of the (retrofitted) heat treatment system, does increase the achievable cycle time, but this is a reasonable concession if only relatively few components are to be partially heat treated if the process can be implemented "in line" for this.
- step c) the mode of operation of the heat treatment system is adapted in such a way that an internal furnace temperature in the second furnace is higher than a (maximum or highest) internal furnace temperature of the continuous furnace (to be retrofitted), in particular if the ( retrofitted) heat treatment system no partial heat treatment is performed or the (retrofitted) heat treatment system is operated in a second operating mode in which no temperature difference is set between a first sub-area and a second sub-area of the component.
- the internal furnace temperature in the second furnace is preferably increased by at least 10 K or even by at least 20 K compared to the (maximum) internal furnace temperature of the continuous furnace (to be retrofitted).
- the increase in the internal furnace temperature in the second furnace has the particular advantage that the conventional process of press hardening can continue to be used with the (retrofitted)
- Heat treatment plant can be realized. A considerable amount of usable furnace length is regularly lost due to the temperature control station. To compensate for this, increasing the temperature in the second oven is a preferred approach. In this way, the required final temperature can be achieved despite the reduced length of the furnace.
- the increase (only) of the temperature in the second furnace offers the advantage that in the event of a standstill, which can lead to the fact that those in a furnace with an increased temperature Components take on too high a temperature, only these few components located in the second furnace have to be discarded so that the damage can be limited. If the temperatures in the first furnace and in the second furnace were to be increased due to the overall reduced furnace length, the entire furnace charge might have to be discarded. In addition to the loss of material, the failure while the furnace is “running empty” would also have to be accepted.
- step c) the mode of operation of the heat treatment system is adapted such that an internal furnace temperature in the second furnace is lower than or just as high as a (maximum) internal furnace temperature of the continuous furnace (to be retrofitted).
- an end of the cycle is selected in the event of (targeted) interruptions so that the second furnace is empty. Then no component may have to be discarded.
- Temperature measurement data from, for example, the first furnace and / or the second furnace, for example, are used to determine the end of the cycle.
- thermoforming an inhomogeneous temperature profile or different temperature zones over the respective oven length in the first oven and / or in the second oven, which can each be designed as a continuous oven.
- different temperature zones are set in the first furnace (in the flow direction), whereas a substantially homogeneous internal furnace temperature is set in the second furnace.
- a method is also proposed for operating a heat treatment plant retrofitted in accordance with a method proposed here, with FIG a first operating mode of the heat treatment system in at least one metallic component by means of the temperature control station a temperature difference between a first sub-area and a second sub-area of the component is set and in a second operating mode of the heat treatment system in at least one further metallic component by means of the temperature control station none (specifically or deliberately set ) The temperature difference between a first sub-area and a second sub-area of the component is set.
- the temperature control station is usually equipped with a component-specific insert, which enables the different temperature control of the first and second areas of a component with a partially different solidity.
- the unit can be replaced by a tunnel element that thermally shields the component from the environment. This reduces the radiation of heat from the component and thus reduces the temperature loss of the component on the way from the first furnace to the second furnace.
- additional heating devices can be provided which keep the interior of the tunnel element at an elevated temperature in order to achieve a significant reduction in heat losses due to the lower temperature difference to the surroundings.
- the tunnel element can particularly preferably be heated in such a way that the internal temperature corresponds approximately to the internal temperature of the first furnace or of the second furnace. As a result, a temperature drop in the component can largely be avoided.
- At least the following steps are carried out during the first operating mode: a) heating the (entire) component in the first furnace, in particular by means of radiant heat and / or convection, preferably by at least 500 K [Kelvin], in particular by at least 650 K or even by at least 750 K, bl) moving the component into the temperature control station, cl) in particular convective cooling of at least a first sub-area of the component in the temperature control station, with a temperature difference of preferably at least 50 K or even at least 100 K between the at least a first sub-area and at least a second sub-area of the component is set, dl) moving the component from the temperature control station into the second oven, el) heating at least the at least one first sub-area of the component in the second oven, in particular by means of radiant heat and / or convection, preferably by at least 100 K, esp ondere by at least 150 K or even by at least 200 K.
- the component (in step a1) move at a speed in the range from 0.01 to 1 m / s [Meters per second] is moved through the first furnace.
- the component is preferably moved through the first furnace at a speed in the range from 0.08 to 0.3 m / s.
- at least the following steps be carried out during the second operating mode: a2) heating the component in the first furnace, in particular by means of radiant heat and / or convection, e2) heating the component in the second furnace, in particular by means of radiant heat and / or convection.
- steps a2 and e2 it is proposed that at least the following steps are carried out between steps a2 and e2: b2) moving the component into the temperature control station, c2) reducing a cooling rate of the component or heating the
- Component in the temperature control station in particular by means of radiant heat, d2) moving the component from the temperature control station into the second furnace.
- FIG. 2 the heat treatment system according to FIG. 1, which has been retrofitted with a method proposed here.
- Fig. 1 shows schematically a known heat treatment system 1, which can be retrofitted with a method proposed here.
- the heat treatment system 1 has a continuous furnace 2, which is (directly) followed by a press hardening tool 7.
- Heat treatment system 1 here represents a press hardening line.
- FIG. 2 shows the heat treatment system 1 according to FIG. 1, which has been retrofitted with a method proposed here.
- the continuous furnace was divided into a first furnace 3 and a second furnace 4.
- a temperature control station 5 was then arranged in the heat treatment system 1, the temperature control station 5 being arranged (directly) after the first furnace 3 and upstream of the second furnace 4 (directly).
- the temperature control station 5 is provided and set up to set a temperature difference between at least one first sub-area and at least one second sub-area of a metallic component 6 to be treated.
- a method for retrofitting a heat treatment system is thus specified which at least partially solves the problems described with reference to the prior art.
- the method allows the retrofitting of a heat treatment system that is partially different on an industrial scale, in particular, that can be carried out as efficiently as possible Heat treatment of a metallic component and, in particular, the most efficient possible implementation of a conventional press hardening process.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Thermal Sciences (AREA)
- Physics & Mathematics (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Tunnel Furnaces (AREA)
- Control Of Heat Treatment Processes (AREA)
- Furnace Details (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102020111615.2A DE102020111615A1 (de) | 2020-04-29 | 2020-04-29 | Verfahren zum Nachrüsten einer Wärmebehandlungsanlage |
PCT/EP2021/059416 WO2021219356A1 (de) | 2020-04-29 | 2021-04-12 | Verfahren zum nachrüsten einer wärmebehandlungsanlage |
Publications (1)
Publication Number | Publication Date |
---|---|
EP4143494A1 true EP4143494A1 (de) | 2023-03-08 |
Family
ID=75530000
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP21718843.2A Pending EP4143494A1 (de) | 2020-04-29 | 2021-04-12 | Verfahren zum nachrüsten einer wärmebehandlungsanlage |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP4143494A1 (zh) |
CN (1) | CN115461588A (zh) |
DE (1) | DE102020111615A1 (zh) |
WO (1) | WO2021219356A1 (zh) |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2369228A1 (fr) * | 1976-10-28 | 1978-05-26 | Secail Jean | Four a longueur variable pour la cuisson en monocouche de produits ceramiques |
DE102009004967B4 (de) | 2009-01-14 | 2010-12-02 | Schwartz, Eva | Verfahren und Vorrichtung zur Ausrichtung von erwärmten Werkstücken |
DE102013107870A1 (de) | 2013-07-23 | 2015-01-29 | Benteler Automobiltechnik Gmbh | Verfahren zur Herstellung von Formbauteilen sowie Formbauteil und Durchlaufofen |
JP7112329B2 (ja) * | 2016-01-25 | 2022-08-03 | シュヴァルツ ゲーエムベーハー | 金属を熱処理する方法及び装置 |
DE102016118252A1 (de) | 2016-09-27 | 2018-03-29 | Schwartz Gmbh | Verfahren und Vorrichtung zur Wärmebehandlung eines metallischen Bauteils |
DE102016121699A1 (de) | 2016-11-11 | 2018-05-17 | Schwartz Gmbh | Temperierstation zur partiellen Wärmebehandlung eines metallischen Bauteils |
-
2020
- 2020-04-29 DE DE102020111615.2A patent/DE102020111615A1/de active Pending
-
2021
- 2021-04-12 EP EP21718843.2A patent/EP4143494A1/de active Pending
- 2021-04-12 CN CN202180031994.1A patent/CN115461588A/zh active Pending
- 2021-04-12 WO PCT/EP2021/059416 patent/WO2021219356A1/de unknown
Also Published As
Publication number | Publication date |
---|---|
CN115461588A (zh) | 2022-12-09 |
WO2021219356A1 (de) | 2021-11-04 |
DE102020111615A1 (de) | 2021-11-04 |
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