Method and system for determining the temperature value of a molten metal bath

Abstract

The present invention relates to a method and a system for determining the temperature value of a molten metal bath. The method according to the invention has proven to be particularly suitable for metallurgical vessel installations which are constantly moved during the metal production process.

Description

Technical Field

[0001] The present invention relates to a method and a system for determining the temperature value of a molten metal bath.

[0002] The temperature of the molten metal bath in a metallurgical vessel is an important parameter during the metal manufacturing process and determines the quality of the resulting product. Possible means for measuring the temperature of molten metal baths, especially iron or steel in the melting environment of an electric arc furnace (EAF), include the step of immersing an optical fiber surrounded by a metal tube into the molten metal. The optical fiber surrounded by the metal tube is often also referred to as an optical core wire.

[0003] To measure the temperature of the molten metal bath, the optical core wire can be sent into the metallurgical vessel. The front end of the optical core wire is immersed in the molten metal bath, where it first encounters a high-temperature atmosphere on the way, followed by a slag layer, and then the molten metal bath. When a portion of the optical core wire is immersed below the surface of the molten metal bath, the optical fiber can transmit the thermal radiation received from the molten metal to a detector, such as a pyrometer. To determine the temperature of the molten metal bath, appropriate instrumentation can be associated with the detector. During this measurement, the immersed portion of the optical core wire can be partially or completely consumed by the molten metal bath. When the temperature measurement is completed, the tip of the optical core wire can be retracted from the molten metal bath. The retracted tip of the optical core wire becomes the new front end for the next temperature measurement.

[0004] Such a device is suitable for on-demand temperature measurement and semi-continuous temperature measurement in the form of a series of immersion cycles. The operator can obtain the temperature measurement value without directly intervening in the harsh environment close to the metallurgical vessel.

[0005] To provide accurate measurement values, a blackbody state must be ensured near the immersed front end of the optical fiber while the measurement values are being acquired. - On the one hand, the fiber must be immersed to a sufficient depth below the surface of the metal bath and at a position within the container representative of the temperature of the liquid metal bath. On the other hand, deep immersion increases the buoyancy acting on the optical core wire and increases the consumption during the measurement sequence.

[0006] Typically, a device including an optical core wire for temperature measurement is fixedly installed at the upper part of a container containing molten metal and is arranged, for example, on a side wall or a part of the roof. For the central position of the electrodes of the system, the measuring device is usually not installed at the center above the molten metal bath. In a typical metallurgical process, the container is moved during the process to assist in the homogenization of the molten metal. This constant movement is generally referred to as "furnace rocking". As those skilled in the art will understand, the container is part of the furnace. This tilting, sliding or rotational movement changes the distance from the surface of the molten metal bath to the installation of the optical core wire and prevents immersion to a constant immersion depth of the optical core wire throughout all stages of the process.

[0007] U.S. Patent Application Publication No. 2003004602 discloses a method of controlling the tilting of a furnace according to the process parameters of a metallurgical process to optimize the yield of each process. The importance of tilting is recognized for the process itself, but the impact on the measurements associated with the process has not been addressed.

[0008] Some prior art documents disclose a method of feeding an optical core wire to improve the data quality of temperature measurement. For example, U.S. Patent Application Publication No. 2018180484 discloses a feeding method having two feeding speeds followed by a stationary time, and then discloses a method for measuring the temperature of a molten metal bath in which temperature measurement is performed. This method solves some of the previously known problems but does not address the constantly changing conditions during the metal manufacturing process. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] In view of the prior art, there is a need for a measurement method and system that take into account the circumstances associated with the metal manufacturing process, and an efficient use method for such methods and systems.

[0010] Accordingly, an object of the present invention is to provide an improved method for determining the temperature value of a molten metal bath using an optical core wire, which solves at least one of the above-described problems. In particular, one of the objects is to provide an improved method for more reliably determining the temperature value in a continuously moving metallurgical vessel. Furthermore, it is an object to provide a method for obtaining the temperature value at a specific immersion depth of the optical core wire below the surface of the molten metal bath. A further aspect of the object of the present invention is to provide a method that enables efficient use of a consumable optical core wire.

[0011] A further object of the present invention is to provide an improved system for carrying out the method of the present invention.

[0012] These objects are achieved by the subject matter defined in the independent claims.

[0013] The present invention is a method for determining the temperature value of a molten metal bath in a furnace using an apparatus comprising an optical core wire and a detector, the furnace having a furnace tilt, the method comprising: (a) providing a data set associating a furnace tilt value FI with a corresponding measurement profile MP; (b) determining a furnace tilt value FI(n) at a time point t(n); (c) selecting a measurement profile MP(n) corresponding to the furnace tilt value FI(n) from the provided data set associating the furnace tilt value FI with the corresponding measurement profile MP; (d) applying the measurement profile MP(n) at the time point t(n) to obtain a measured temperature value; A method including the above is provided.

[0014] Furthermore, the present invention is a system for determining the temperature value of a molten metal bath in a furnace, the furnace having a furnace tilt, the system comprising an apparatus and a module, the module being adapted to interact with the apparatus, the apparatus including an optical core wire and a detector, the module including a storage unit S, a processing unit P, and a control unit C, the storage unit S including - a storage element S1 for providing a data set associating a furnace tilt value FI with a corresponding measurement profile MP including The processing unit P - a processing element P1 for measuring the furnace tilt FI, and - a processing element P2 for selecting a measurement profile MP(n) corresponding to the furnace tilt FI(n) from the provided data set associating the furnace tilt value with the corresponding measurement profile MP including The control unit C - a control element C1 for applying the measurement profile MP(n) to obtain a measured temperature value provides a system including

[0015] More preferred embodiments are defined in the dependent claims. The preferred embodiments may be realized individually or in any possible combination.

[0016] The method according to the invention has proven to be particularly suitable for installations of metallurgical furnaces that can be continuously moved during the metal production process. Surprisingly, it has been found that the data quality of the measurements depends on the measurement profile applied to obtain the measurement values. In particular, the feeding of the optical core wire into the molten metal bath has been identified as a factor that significantly affects the reliability of the data obtained. The method of the invention enables the determination of temperature values using a measurement protocol that adapts to the various different configurations of the metallurgical vessel containing the molten metal bath. In particular, it has been found that a constant immersion depth of the front end of the optical core wire is an important parameter for the measurement quality obtained. The "quality" in this context refers to the measurement accuracy obtained compared to the data obtained using a fixed standard thermocouple. In addition, the method of the invention further enables the acquisition of accurate temperature values with minimal consumption of the optical core wire by enabling the positioning of the optical core wire and its front end to a certain depth below the surface of the molten metal bath. The term "consumption" as used herein refers to damage to the optical core wire, such as melting and dissolution of the optical core wire by and in the molten metal bath, decomposition or combustion of the entire optical core wire or different parts thereof.

[0017] The present invention provides a method for determining the temperature value of a molten metal bath.

[0018] "Determining the temperature value" may be used herein as a synonym for measuring the temperature. According to a preferred embodiment, the temperature value may be determined by single-point measurement or by multi-point measurement.

[0019] Throughout this application, variables related to temperature or temperature value are referred to by the capital letter T, while variables related to a general point in time, length of time or time are referred to by the lower case letter t.

[0020] When defining general variables, variables without specified subscripts, such as (n), etc., are used. When referring to this variable in a specific context, variables with specified subscripts are used. For example, FI refers to the general definition of the furnace tilt value, and FI(n) refers to a specific furnace tilt value.

[0021] As used herein, the term "molten metal bath" is used to describe the melt in a furnace, particularly in a vessel. An alternative term for "molten metal bath" known to those skilled in the art is "molten metal". The molten metal in the molten metal bath is not particularly limited. According to a preferred embodiment, the molten metal is molten steel. The term "molten metal bath" does not exclude the presence of any solid or gaseous portions, for example, including the non-molten portions of each metal. The molten metal bath may be covered with a slag layer. The term "slag" refers to non-steel by-products that are often produced in steelmaking furnaces and typically exist as molten materials floating on the molten metal. The slag may include metal oxides, metal sulfides, calcium oxide, magnesium oxide, magnesite, dolomite, iron oxide, aluminum oxide, manganese oxide, silica, sulfur, phosphorus, or combinations thereof.

[0022] The temperature of the molten metal varies and usually depends on the composition of the metal and the stage of the melting process. According to a preferred embodiment, the temperature of the molten metal bath is in the range of 1500 to 1800 °C, more preferably in the range of 1500 to 1700 °C.

[0023] The molten metal bath whose temperature is measured by the method of the present invention is disposed in a furnace.

[0024] Preferably, the furnace is a metallurgical plant comprising a vessel for containing the molten metal bath and equipment fixedly installed on or in the vessel. Such equipment can be, for example, heating means as electrodes and measuring means as equipment including an optical core wire.

[0025] The molten metal bath may be contained within a vessel that includes an entrance suitable for feeding an optical core wire. Such an entrance may be disposed on a sidewall panel, a roof covering the vessel, or a platform installed above the vessel such as a platform found in an eccentric bottom tapping (EBT) furnace. Preferably, the entrance is disposed on the EBT furnace platform.

[0026] As used herein, the term "furnace tilt" refers to the degree to which the furnace, particularly the vessel containing the molten metal bath, tilts. Preferably, the tilt is defined with respect to a pivot axis A P and is preferably defined with respect to pivot axis A P which defines an initial position. As will be understood by those skilled in the art, furnace tilt is a direct result of the rocking of the furnace commonly used during the metallurgical process. Preferably, when the bottom of the vessel containing the molten metal bath is flat, the pivot axis A P defining the initial position is oriented perpendicular to the bottom. When the bottom is rounded or of another shape, the pivot axis A P defining the initial position is preferably oriented perpendicular to the projection plane defined by the outer contour of the vessel. It will be understood that the pivot axis A P should not be located at the center of the vessel, i.e., should not be located at a position half the width of the vessel. In particular, when the vessel is not symmetrically constructed, the position of the pivot axis A P may be offset to one side with respect to the center defined by the width of the vessel.

[0027] In a preferred embodiment, the furnace tilt is defined by the angle between the horizontal plane and a reference plane that contacts the bottom of the furnace body, and when the furnace is in its initial position, i.e., the neutral position, the reference plane is substantially parallel to the horizontal plane and / or the surface of the molten metal bath.

[0028] The furnace tilt value is preferably expressed in degrees. The furnace tilt value can take a positive or negative value depending on the direction in which the vessel tilts with respect to the pivot axis A P defining the initial position. By definition, the initial position refers to a furnace tilt value of 0°. In other words, a positive value of furnace tilt is with respect to the pivot axis AP refers to the tilting in one direction, and a negative value can refer to the tilting in the opposite direction. Typically, the pivot axis A that defines the initial position P The tilting of the container with respect to is in the range of +5° to -5°.

[0029] Preferably, the tilting of the furnace results in the movement of the molten metal bath. Those skilled in the art will understand that the tilting affects the relative positioning and distance between the surface of the molten metal bath and a part of the container that surrounds the interior, such as a lid covering the container. Since the volume of the molten metal bath is constant after all the supplied solid materials have melted, the position of the level of the surface of the molten metal bath is affected on the one hand by the tilting of the furnace and on the other hand by the geometric shape of the inner cylinder of the container.

[0030] It should be understood that for the present invention, "tilting of the furnace" is referred to as movement in one dimension, i.e., movement from one side to the other side, or from the front to the back.

[0031] The furnace can be tilted over an angular range using a tilting device. Preferably, the tilting device includes means selected from the group consisting of a motor, a gear, a chain drive, a hydraulic pressure, and combinations thereof.

[0032] In a preferred embodiment, the tilting of the furnace is performed by an operator who manually operates the tilting device. In an even more preferred embodiment, the tilting of the furnace is computer-controlled. For example, the tilting of the furnace is controlled by a processor or a programmable logic controller. In such an embodiment, the processor or the programmable logic controller can command the tilting device to perform a series of small (equal or unequal) angular movements or continuous angular movements.

[0033] Preferably, the container includes the position where the optical core wire starts to be sent. In a preferred embodiment, this position is at the opening of the furnace, i.e., the entrance through which the optical core wire is sent into the container.

[0034] Preferably, the position where the optical core wire starts to be fed is not on the pivot axis A. P In other words, the position where the optical core wire starts to be fed is not the center within the container. Here, the position of the "center of the container" should be understood as a point within the container located at half the width of the diameter of the container. Preferably, the position where the optical core wire starts to be fed is adjacent to the side wall of the container.

[0035] As those skilled in the art will understand, the resulting difference in the distance between the position where the optical core wire starts to be fed and the surface of the molten metal bath increases as this position moves away from the central position within the container. In other words, the closer that point is to the side wall of the container, the more prominent the influence of the tilting movement of the furnace becomes.

[0036] In a typical container configuration, the difference in the distance from the surface of the molten metal bath to the position where the optical core wire starts to be fed can be up to 10 cm per degree of tilt. That is, a tilt from +3° to -3° results in a maximum difference of 60 cm in the distance from the surface of the molten metal bath to the position where the optical core wire starts to be fed.

[0037] The present invention provides a method for determining a temperature value using an apparatus comprising an optical core wire. Preferably, the optical core wire is an optical fiber surrounded laterally by a metal tube. Preferably, the optical fiber is a flexible and transparent fiber. The optical fiber is most often used as a means for transmitting light, especially within the IR wavelength range, between two ends of the fiber. Preferably, the optical fiber is formed from glass or plastic, more preferably silica glass. Preferably, the optical fiber is selected from the group consisting of graded index fibers and single mode step index fibers.

[0038] The metal tube surrounding the optical fiber may completely surround the optical fiber, but the casing may be at least partially open so as not to completely surround the optical fiber.

[0039] Preferably, the metal of the metal tube surrounding the optical fiber is iron or steel, preferably stainless steel.

[0040] In a preferred embodiment, the linear density of the optical core wire is in the range of 25 to 80 g / m, more preferably in the range of 35 to 70 g / m. The linear density is defined by the mass per unit length.

[0041] Preferably, the optical core wire is surrounded laterally by at least one additional metal tube, i.e., at least two metal tubes surround the optical fiber laterally. Preferably, the optical core wire is disposed at the center of at least one additional metal tube.

[0042] Preferably, at least one additional metal tube is not in contact with the optical core wire. More preferably, the gap between these at least two metal tubes is at least partially filled with a material selected from the group consisting of a gaseous material, a solid material, or a combination thereof. The solid material is preferably selected from the group consisting of inorganic materials, natural polymers, synthetic polymers, and combinations thereof. The gaseous material is preferably a gas or a mixture of gases. More preferably, the gas is air or an inert gas.

[0043] According to a preferred embodiment, the optical core wire comprises a plurality of separating elements disposed within at least one metal tube, and these separating elements form at least one compartment between the separating elements. Here, the term "compartment" relates to the volume between different separating elements within the tube. The term "separating element" relates to a portion disposed within the tube that subdivides the volume within the tube. Preferably, the separating element is a disc-shaped element disposed inside the tube, the disc-shaped element has an opening, the optical core wire extends through the opening, and the opening can at least partially support the optical core wire. The material of the separating element is preferably selected from the group consisting of silicone, preferably two-component silicone, rubber, leather, cork, metal, and combinations thereof.

[0044] Preferably, the metal tube surrounding the optical core wire is surrounded by a further layer. According to certain preferred elements, the further layer is at least one further metal tube layer or a layer comprising at least a plurality of parts, preferably fibres.

[0045] In a more preferred embodiment, the material of at least one additional layer has the form of a woven structure, a mesh structure, a fabric structure or a knitted structure.

[0046] Preferably, at least one additional layer comprises a non-metallic material, most preferably an organic material.

[0047] It should be understood that the optical core wire can comprise any combination of the above-described configurations. According to certain preferred embodiments, the optical core wire is surrounded laterally by a further layer and a second metal tube.

[0048] The apparatus used to apply the method according to the invention further comprises a detector. The detector is coupled to one end of the optical core wire and receives an optical signal transmitted by an optical fibre, in particular within the IR wavelength range. Preferably, the detector in the context of the present invention is a pyrometer.

[0049] The optical core wire has an immersion end and an opposite end. The front end of the optical core wire is the tip of the immersion end of the optical core wire. Preferably, when the method according to the invention is applied, the optical core wire is consumed in the direction from the immersion end towards the opposite end and, after each measurement sequence, another part of the optical core wire becomes the immersion end. That is, after each measurement sequence, a new front end is generated. The opposite end is connected to the detector and is not consumed during the measurement.

[0050] In step (a) of the method according to the invention, a data set is provided that associates the furnace tilt value FI with the corresponding measurement profile MP.

[0051] Preferably, the data set includes data pairs in which one specific value of one type of data is assigned to a specific value of another type of data. More preferably, the data set may include data pairs in which one specific value of one type of data is assigned to a model or a sequence of several steps, etc.

[0052] The measurement profile MP should be understood as a series of steps carried out to obtain a target value. In the context of the present invention, the target value is the temperature of the molten metal bath.

[0053] In a preferred embodiment, the measurement profile MP defines at least one step of providing the front end of the optical core wire at a first position p1 above the surface of the molten metal bath.

[0054] The first position p1 may be above the container containing the molten metal bath or inside the container. The front end at the first position p1 may optionally be in contact with the slag layer that may be present or may not be in contact.

[0055] Preferably, the first position p1 is not on the pivot axis A P i.e., the first position p1 is not at the center above the molten metal bath. Preferably, the first position p1 is adjacent to the side wall of the container.

[0056] In a preferred embodiment, the measurement profile MP defines at least one step of sending the front end of the optical core wire from the first position p1 towards the molten metal bath to a second position p2.

[0057] Those skilled in the art will understand that "providing the front end" and "sending the front end" necessarily include supplying and moving the optical core wire, i.e., supplying the optical core wire having the front end and moving the optical core wire together with its front end.

[0058] The second position p2 is preferably located below the first position p1 in a direction defined from a point above the surface of the molten metal bath towards a point at the level of the surface of the molten metal bath.

[0059] Preferably, the measurement profile MP defines a feed from the first position p1 towards the second position p2 towards the molten metal bath during the time between two instants t0 and t2. It should be understood that t2 is after t0.

[0060] Preferably, the measurement profile MP defines at least one feed rate v at which the front end of the optical core wire is sent from the first position p1 towards the molten metal bath to the second position p2. fed defines.

[0061] The feed rate v fed should be understood to refer to the average speed while sending the front end towards and below the surface of the molten metal bath.

[0062] Preferably, the feed rate v fed is defined according to a predetermined distance between the first position p1 and the second position p2. By defining the feed rate v according to the distance between the first position p1 and the second position p2, preferably, the time during which the front end of the optical core wire is exposed to the harsh environment inside the metallurgical vessel becomes constant regardless of the distance that the front end has to be sent from the first position p1 to the second position p2. Preferably, the feed rate v fed is defined such that the longer the distance between the first position p1 and the second position p2, the faster it is. fed is defined such that the longer the distance between the first position p1 and the second position p2, the faster it is.

[0063] In a preferred embodiment, the feed is performed at at least two feed rates v fed 1 and v fed 2. It should be understood that the feed rates v fed 1 and v fed 2 refer to the average speed at which the front end of the optical core wire is sent.

[0064] Preferably, the front end of the optical core wire passes through the surface of the molten metal bath at a third position p3. The third position p3 is preferably located below the first position p1 and above the second position p2.

[0065] The surface of the molten metal bath may be the surface facing the atmosphere of the container, or, when a slag layer is present, may be the surface facing the slag layer.

[0066] Preferably, the second position p2 is at an immersion depth i1 below the surface of the molten metal bath. The immersion depth in the present invention should be understood as the distance of the front end from the surface of the molten metal bath and is measured along an axis perpendicular to the surface. That is, the immersion depth i1 is the distance between the third position p3 and the second position p2.

[0067] Preferably, the front end of the optical core wire is located below the surface of the molten metal bath during the time within two time points t1 and t2. It should be understood that the two time points t1 and t2 are after the time point t0, and the time point t2 is after the time point t1. The time point t1 is the time when the front end enters the molten metal bath, that is, the time when the front end is immersed below the surface of the molten metal bath. In other words, t1 is the time when the front end passes through the third position p3.

[0068] Preferably, the measurement profile MP defines a first feed rate v fed 1 at which the front end is fed during the time within the time points t0 and t1, and a second feed rate v fed 2 at which the front end is fed during the time within the time points t1 and t2.

[0069] In a preferred embodiment, the second feed rate v fed 2 includes two or more feed rates.

[0070] An immersion angle within the range of 45 to 90°, preferably within the range of 60 to 90°, and most preferably an immersion angle of 90° can be advantageous. This angle is defined as the angle between the surface of the molten metal bath and the optimal straight axis along the optical core wire. 90° can be understood as the immersion of the optical core wire perpendicular to the surface of the molten metal bath.

[0071] In a preferred embodiment, the measurement profile MP defines at least one step of acquiring temperature information during the measurement time within time points t0 and t2. Preferably, the measurement profile MP defines a step of acquiring temperature information during the measurement time within time points t1 and t2.

[0072] To acquire the temperature information, radiation emitted by the molten metal bath, particularly within the IR wavelength range and conveyed by the optical core wire to the detector, is recorded. The intensity and / or spectral information of the radiation may be processed by a processing unit connected to the detector. The front end of the optical core wire is preferably immersed below the surface of the molten metal bath at the time when the temperature is acquired or during the measurement time.

[0073] Preferably, the temperature information is acquired in a step that results in the determination of a measured temperature value. According to a preferred embodiment, the temperature value may be determined by single-point measurement or multi-point measurement.

[0074] Preferably, the measured temperature value is the average value of a series of data points. More preferably, the measured temperature value is derived based on the application of an algorithm that processes a series of data points.

[0075] According to a preferred embodiment, the measurement profile MP defines a process during the stationary time within time points t0 and t2, during which the feed of the front end of the optical core wire is temporarily stopped or the front end of the optical core wire is fed at a low speed. Preferably, the measurement profile MP defines a stationary time within time points t1 and t2. As used herein, "temporarily stopping the feed of the front end" means not actively moving the front end. In either alternative of temporarily stopping the feed or feeding at a low speed, the movement of the position of the front end towards the surface of the molten metal bath is caused by consumption. Nevertheless, the front end remains immersed below the surface of the molten metal bath.

[0076] The low speed is preferably a speed of less than 0.2 m / s, more preferably a speed of less than 0.1 m / s.

[0077] In a preferred embodiment, the measurement profile MP defines at least one process of retracting the front end of the optical core wire to a position above the molten metal bath at a speed v ret . The speed v ret may be slower than, the same as, or faster than the feed speed v fed .

[0078] Those skilled in the art will understand that retracting the front end of the optical core wire is a movement in the direction from the molten metal bath to a position above the molten metal bath.

[0079] Preferably, after time point t2, the front end of the optical core wire is retracted towards a position above the surface of the molten metal bath.

[0080] Preferably, the front end of the optical core wire is retracted toward the first position p1. Since the front end of the optical core wire is consumed and continuously reconstructed during the measurement sequence defined by the measurement profile MP, the distance between the front end and the first position p1 becomes shorter even when the feed is temporarily stopped and while the front end is immersed below the surface of the molten metal bath. Therefore, it is preferable that the distance by which the front end of the reconstructed optical core wire is retracted is shorter than the distance by which the first front end of the optical core wire is fed from the first position p1 to the second position p2.

[0081] Preferably, the front end of the optical core wire is retracted to the fourth position p4. Preferably, the fourth position p4 is the same as the first position p1.

[0082] Preferably, the measurement profile MP is (i) providing the optical core wire with its front end at a first position p1 above the surface of the molten metal bath; (ii) feeding the front end directed toward the molten metal bath from the first position p1 to a second position p2 at an immersion depth i1 below the surface of the molten metal bath at least at one feed rate v fed over a time within time points t0 and t2, wherein the front end of the optical core wire is below the surface of the molten metal bath during the time within time points t1 and t2; (iii) obtaining temperature information during the measurement time within time points t1 and t2; (iv) retracting the optical core wire at a speed v ret to a position above the molten metal bath; and defining at least one of them.

[0083] Preferably, steps (i), (ii) and (iv) are performed in a continuous order.

[0084] Preferably, step (iii) is performed at least partially during step (ii).

[0085] Preferably, the data set associating the furnace tilt value FI with the corresponding measurement profile MP associates the definition of at least one parameter in at least one step of the measurement profile MP with the furnace tilt value FI.

[0086] The parameter in this context should be understood as at least one position, velocity, and time point defined in at least one step as defined in the measurement profile MP.

[0087] Preferably, the distance between the first position p1 and the second position p2 in the measurement profile MP is defined based on the furnace tilt value FI.

[0088] Preferably, the distance between the first position p1 and the second position p2 is about 2 cm to 20 cm, preferably 5 cm to 15 cm, and most preferably 8 cm to 12 cm for each degree of tilt of the furnace from a predetermined initial position. Adjustment The term "predetermined initial position" refers to the position having a furnace tilt value of 0°, that is, the position defining the neutral position by definition.

[0089] In a preferred embodiment, the distance between the first position p1 and the second position p2 is by the same length for each degree of tilt of the furnace in the first direction and the second direction from a predetermined initial position. Adjustment This embodiment may be preferred when the container containing the molten metal bath is symmetrically constructed.

[0090] In a more preferred embodiment, the distance between the first position p1 and the second position p2 is by the first length for each degree of tilt of the furnace in the first direction from a predetermined initial position. Adjustment and by the second length for each degree of tilt of the furnace in the second direction. Adjustment This embodiment may be preferred when the container is asymmetrically constructed or when the pivot axis A P is not centered.

[0091] Preferably, the distance between the first position p1 and the second position p2 is extended by 2 cm to 20 cm, preferably 5 cm to 15 cm, and most preferably 8 cm to 12 cm for each inclination of the furnace in the first direction from a predetermined initial position.

[0092] Preferably, the distance between the first position p1 and the second position p2 is shortened by 2 cm to 20 cm, preferably 5 cm to 15 cm, and most preferably 8 cm to 12 cm for each inclination of the furnace in the second direction from a predetermined initial position.

[0093] Preferably, the distance between the second position p2 and the fourth position p4 in the measurement profile MP is defined based on the furnace inclination value FI.

[0094] Preferably, the distance between the first position p1 and the second position p2 is the same length as the distance between the second position p2 and the fourth position p4 for each inclination of the furnace. Adjustment is made.

[0095] Preferably, the distance between the second position p2 and the fourth position p4 is about 2 cm to 20 cm, preferably 5 cm to 15 cm, and most preferably 8 cm to 12 cm for each inclination of the furnace from a predetermined initial position. Adjustment is made.

[0096] In a preferred embodiment, the distance between the second position p2 and the fourth position p4 is the same length for each inclination of the furnace in the first direction and the second direction from a predetermined initial position. Adjustment This embodiment may be preferred when the container containing the molten metal bath is symmetrically constructed.

[0097] In a more preferred embodiment, the distance between the second position p2 and the fourth position p4 is by a first length for each inclination of the furnace in the first direction from a predetermined initial position. Adjustment is made, and by a second length for each inclination of the furnace in the second direction. Adjustment is made. This embodiment may be preferred when the container is asymmetrically constructed or when the pivot axis A P is not centered.

[0098] Preferably, the distance between the second position p2 and the fourth position p4 is extended by 2 cm to 20 cm, preferably 5 cm to 15 cm, and most preferably 8 cm to 12 cm for each degree of inclination of the furnace in the first direction from a predetermined initial position.

[0099] Preferably, the distance between the second position p2 and the fourth position p4 is shortened by 2 cm to 20 cm, preferably 5 cm to 15 cm, and most preferably 8 cm to 12 cm for each degree of inclination of the furnace in the second direction from a predetermined initial position.

[0100] Preferably, the data set associating the furnace inclination value FI with the corresponding measurement profile MP further associates the measurement profile with the characteristics of the optical core wire.

[0101] Preferably, the characteristic of the optical core wire is its linear density. The linear density is defined by the mass per unit length.

[0102] Preferably, the length of the time within t0 and t2 of the measurement profile MP is defined to be longer as the linear density of the optical core wire is higher.

[0103] Preferably, the feed rate v of the measurement profile MP fed is defined to be lower as the linear density of the optical core wire is higher.

[0104] In step (b) of the method according to the present invention, the furnace inclination value FI(n) at time point t(n) is determined.

[0105] Preferably, the furnace inclination value FI(n) refers to the value of the furnace inclination at time point t(n).

[0106] There is a range of possibilities available for determining the furnace tilt value FI. In a preferred embodiment, the furnace tilt value FI is determined by direct measurement based on a detection system implemented within, on, or in connection with the metallurgical vessel, an input based on data from a process control mechanism for furnace tilt, or an input based on a known point in the metal production process. The detection system may include, but is not limited to, a rotary variable capacitance sensor, an inductive sensor, and a DC servo motor sensor.

[0107] In step (c) of the method according to the invention, from the provided data set associating the furnace tilt value with the corresponding measurement profile MP, the measurement profile MP(n) corresponding to the furnace tilt value FI(n) is selected.

[0108] In step (d) of the method according to the invention, the measurement profile MP(n) is applied at the time point t(n) in order to obtain the measured temperature value.

[0109] By applying the measurement profile MP(n), the measured temperature value of the molten metal bath at the time point t(n) is determined.

[0110] Preferably, the temperature information is obtained at a predetermined immersion depth i1.

[0111] By obtaining the temperature information at a predetermined immersion depth, the most accurate and reproducible measurement results can be obtained.

[0112] Preferably, the immersion depth i1 is constant. That is, the immersion depth i1 is independent of the furnace tilt value FI. In other words, the measurement profile MP(n) selected in step (c) is selected in relation to the furnace tilt value FI(n) such that the feeding of the front end of the optical core wire results in immersion to a specific immersion depth i1 of the front end. As will be understood by those skilled in the art, the immersion depth i1 may be controlled by the distance between a first position p1 and a second position p2 defined in the measurement profile MP.

[0113] Preferably, steps (b) to (d) are performed in a continuous order.

[0114] Preferably, step (a) is carried out before steps (c) to (d).

[0115] More preferably, the method is in the following order: (a)-(b)-(c)-(d) or (b)-(a)-(c)-(d).

[0116] In a preferred embodiment, the data set provided in step (a) further associates the level of the surface of the molten metal bath with the measurement profile MP.

[0117] Preferably, the method includes determining the level of the surface of the molten metal bath.

[0118] A variety of methods for determining the level of the molten metal bath are known to those skilled in the art. Such methods include, but are not limited to, determining the known density of the molten material and the charge mass of the raw material in combination with the design of the container or the application of the measuring device. Such measuring devices can be a contact sensor as an immersion lance, or a non-contact sensor based on radar, microwave, infrared, electromagnetic, inductive signal detection or optical signal detection, and also a sensor that utilizes an indirect method such as the measurement of the pressure inside the container. Preferably, the sensor is arranged above the molten metal bath in the container so as to capture data indicating the distance between the sensor and the surface of the molten metal.

[0119] Preferably, the level of the molten metal bath is determined at the initial position, i.e., with a furnace tilt value FI of 0°.

[0120] In a preferred embodiment, the data set provided in step (a) further associates the position of the front end of the optical core wire with the measurement profile MP.

[0121] Preferably, the method includes determining the position of the front end of the optical core wire.

[0122] Preferably, the position of the front end of the optical core wire is determined by a sensor. Such a sensor may be selected from the group consisting of a pneumatic sensor, an inductive sensor, and an optical sensor.

[0123] According to a preferred embodiment of the present invention, the procedures described herein are repeatedly executed.

[0124] The present invention further provides a system for determining the temperature value of a molten metal bath in a furnace, the furnace having a furnace tilt. The system comprises an apparatus and a module, the module being adapted to interact with the apparatus.

[0125] Preferably, the system is a method according to the present invention, (a) providing a data set associating a furnace tilt value FI with a corresponding measurement profile MP; (b) determining a furnace tilt value FI(n) at a time point t(n); (c) selecting a measurement profile MP(n) corresponding to the furnace tilt value FI(n) from the provided data set associating the furnace tilt value FI with the corresponding measurement profile MP; (d) applying the measurement profile MP(n) at the time point t(n) to obtain a measured temperature value; and is configured to execute a method comprising the above steps.

[0126] For a preferred embodiment of the method of the present invention, reference may be made to the above preferred embodiments.

[0127] The system according to the present invention comprises an apparatus, the apparatus including an optical core wire and a detector. For a preferred embodiment of the optical core wire and the detector, reference may be made to the above preferred embodiments described for the method of the present invention.

[0128] The system according to the present invention includes a module, the module including a storage unit S, a processing unit P, and a control unit C.

[0129] Preferably, the memory unit S, the processing unit P, and the control unit C are configured to interact with each other.

[0130] According to the present invention, the memory unit S of the module includes a memory element S1 for providing a data set that associates the furnace tilt value FI with a corresponding measurement profile MP.

[0131] According to the present invention, the processing unit P of the module includes a processing element P1 for determining the furnace tilt value FI and a processing element P2 for selecting a measurement profile MP(n) corresponding to the furnace tilt FI(n) from the provided data set that associates the furnace tilt value FI with a corresponding measurement profile MP.

[0132] In a preferred embodiment, the processing unit P is configured to process the information stored in the memory unit S.

[0133] According to the present invention, the control unit C of the module includes a control element C1 for applying the measurement profile MP(n) to obtain a measured temperature value. The control element C1 is preferably a processor or programmable logic.

[0134] In a preferred embodiment, the control unit C is configured to control the device.

[0135] In a preferred embodiment, the system comprises feeding means. In the context of the present invention, the feeding means can be understood as means enabling the feeding of the optical core wire into the molten metal bath. Such means can be selected from the group consisting of a feeder, a feed control device, a straightener, a guide tube, and combinations thereof.

[0136] According to a preferred embodiment, the system further comprises a coil corresponding to the length of the optical core wire.

[0137] According to a preferred embodiment, the system further comprises a tilting device. Preferably, the tilting device includes one means selected from the group consisting of a motor, a gear, a chain drive, a hydraulic pressure, and combinations thereof.

[0138] According to a preferred embodiment, the control unit of the module includes a control element C2 for controlling the tilting device. The control element C2 is preferably a processor or programmable logic.

Brief Description of the Drawings

[0139] The concept underlying the present invention will be described in more detail hereinafter with respect to the embodiments shown in the drawings. However, it should be understood that the present invention is not limited to the exact configurations and means shown. Here,

Figure 1

Figure 2

Figure 3

Figure 4A

Figure 4B

Figure 4C

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

[0140] FIG. 1 is a schematic cross-sectional view of various designs of an optical core wire according to an exemplary embodiment of the present invention. FIG. 1A shows an optical core wire 1' including an optical fiber 2' surrounded by a metal tube 3'.

[0141] FIG. 1B shows an optical core wire 1'' including an optical fiber 2'' surrounded by a metal tube 3''. A second metal tube 4'' further surrounds the metal tube 3''. The gap 5'' between the two metal tubes is not filled with a solid material. That is, the gap may contain a gas or a gas mixture.

[0142] FIG. 1C shows an optical core wire 1''' including an optical fiber 2''' surrounded by a metal tube 3''' and a second metal tube 4'''. The gap 5''' between the two metal tubes is filled with a filling material, for example, an organic material or a fiber from E-glass.

[0143] FIG. 2 is a schematic diagram of an exemplary facility 6 having a molten metal bath 7 in which the temperature is determined.

[0144] The facility 6 includes an optical core wire 1 that is at least partially installed on a coil 8 and is at least partially unwound from the coil 8 for measurement. One end of the optical core wire 9 is connected to a detector 10, and the detector 10 can be connected to a computer system (not shown) for processing data acquired by the optical core wire 1 and the detector 10.

[0145] The molten metal bath 7 is accommodated in a container 11 which can be part of an electric arc furnace (EAF) or any converter known to those skilled in the art of molten metal treatment. The optical core wire 1 is guided by a moving means 12 through a guide tube 13 in the container 11 having an entrance 14. The moving means 12 includes rollers for moving the optical core wire 1 and may include a servo motor for driving at least one of the rollers. The illustrated configuration is used as an example, and the lid 22 having each entrance 14 is not a prerequisite of the present invention.

[0146] The illustrated configuration shows an exemplary measurement position p2 of the optical core wire 1 in a state where the front end 15 is immersed below the surface of the molten metal bath MB S In the present embodiment, the immersion angle of the optical core wire 1 with respect to the surface of the molten metal bath MB S is 90°. However, this angle is variable depending on the details of the structure of the metallurgical equipment.

[0147] The temperature of a part of the optical core wire 1 extending from the coil 8 to the entrance 14 of the container can be considered low and can be in the range of room temperature to 100 °C. When passing through the entrance 14 in the direction of the molten metal bath 7, it first encounters a high-temperature atmosphere of up to 1700 °C or higher, then encounters the slag layer 17, and then encounters the molten metal bath 7. A blowing lance 18 can be provided at the entrance 14 to the container to prevent the intrusion of metal and slag into the guide tube 13.

[0148] The molten metal bath MB S The optimal level of can be approximately known for each metallurgical container depending on its design and operating mode.

[0149] To obtain temperature measurement values, the front end of the optical core wire 1 is sent to the required immersion depth at the position p2 towards the molten metal bath 7 at the immersion end 15. In order to obtain reliable temperature measurement values, it may be desirable to measure at a substantially constant immersion depth in the molten metal bath. A suitable feeding system 12 accurately controls the feeding speed of the optical core wire 1.

[0150] After the measurement sequence, the portion 19 of the optical core wire immersed in the molten metal bath is melted and thus consumed. The length of this portion is L C as shown. The length L c should be understood to correlate with the immersion depth reached by the optical core wire. After the measurement is made, the portion 20 of the optical core wire located within the high-temperature atmosphere and extending through the slag layer may be fed back in the direction of the coil 8 and reused for the next measurement. The length L D correlates with the length of the optical core wire that is disposed within the vessel but not consumed during the measurement. The total length L T of the optical core wire fed into the metallurgical vessel c is the sum of the consumed length L D and the length L

[0151] Figure 3 is a detailed schematic view of a furnace 110, particularly an EAF, having a typical installation with an optical core wire 1 for temperature measurement. An EAF used for steelmaking typically includes a vessel 11 that houses a molten metal bath 7, a removable lid 22 through which one or more electrodes 23 can penetrate into the furnace, and a platform 24 disposed on the side of the vessel 11. As shown in the figure of the EAF, the body that houses the molten metal bath 7 does not necessarily have to be symmetric with respect to the central axis A P and can also be designed asymmetrically. The electrodes 23 used to heat the metal are typically disposed above the vessel 11.

[0152] The entrance 14 through which the optical core wire 1 enters the vessel 11 is disposed on the platform 24. An immersion device including a moving means 12 is also disposed on the platform 24 (not shown for clarity). The illustrated configuration shows the vessel 11 in a typical neutral position, i.e., not tilted.

[0153] In such an EAF configuration during operation, i.e., with the metal melted in the molten metal bath charged, the depth of the molten metal bath is within the range of 1 m, and the distance from the inlet 14 to the surface of the molten metal bath is within the range of 1 to 1.5 m. The typical inner diameter of such a vessel is 6 m to 7 m, but larger facilities with an inner diameter of up to 9 m are also common. The distance from the center of the EAF to the inlet 14 installed on the platform is within the range of 3 m to 3.5 m. The numbers are not drawn to scale in all the figures, and it is emphasized that the items are shown in size ratio to clarify the situation related to the present invention.

[0154] Figure 4 is a schematic view of an exemplary furnace 110' having a metallurgical vessel 11' with various furnace tilt angles. It will be understood that the elements and their ratios to each other are not drawn to scale but are drawn to explain the present invention in more detail. Typically, the tilt of the vessel is within the range of +3° to -3°, and a tilt of 10° as shown in the figure is selected for better clarity.

[0155] The optical core wire 1 is guided into the vessel 11' through an inlet 14 located near the side wall of the vessel. The inlet 14 may also be at the same position as the first position p1, and in an exemplary measurement profile, it is where the optical core wire starts to be sent. The position reached by the front end of the optical core wire is marked as p2 in Figure 4A, but for better clarity, the mark is omitted in Figures 4B and 4C.

[0156] Figures 4A - 4C show the relationship between the surface of the molten metal bath MB S and the central pivot axis A P where the furnace tilt value is indicated, and the horizontal plane P T which can also be used to define the furnace tilt values in various different configurations of the vessel 11'. Further, the length L H of the optical core wire immersed below the surface of the molten metal bath MB S and the length L c of the optical core wire that enters the vessel 11' but is not immersed below the surface of the molten metal bath MB S of the molten metal bath.D The total length L of the optical core wire contained in the container 11’, defined as the sum with T is shown for these various furnace configurations.

[0157] Figure 4A shows the container 11’ in a representative neutral position, with a furnace tilt value of 0° indicated. The pivot axis A P is configured perpendicular to the bottom of the container 11’ and coincides with the tilt axis A T Both axes are perpendicular to the horizontal plane P that coincides with the bottom of the container 11’ H

[0158] Figure 4B shows the container 11’ in a position tilted 10° to one side. The furnace tilt value is defined by the angle between the pivot axis A P and the tilt axis A T Alternatively, the furnace tilt value may be defined by the angle between the horizontal plane P H and the bottom of the container 11’.

[0159] Figure 4C shows the container 11’ in a position tilted 10° to the other side. By definition, the furnace tilt value has a negative sign.

[0160] Figures 4A - C show a configuration in which the total length of the optical core wire L T contained in the container 11’ is constant. The tilting of the furnace affects the immersion depth of the front end of the optical core wire 1, represented by the length L S of the optical core wire immersed below the surface of the molten metal bath MB c The object of the present invention was to take into account this changing immersion depth due to the moving furnace 110’ when performing temperature measurement.

[0161] Figure 5 shows further exemplary metallurgical furnace container shapes with respect to the pivot axis A P For clarity, additional parts are not shown. Figure 5A shows a furnace 110’’ having a round - bottomed container 11’’ with the pivot axis A P disposed at the center of the neutral position. Figure 5B shows a furnace 110’’’ having an asymmetric container 11’’’. The container 11’’’ has the pivot axis A​P When tilted from, the molten metal bath MB S level moves to different ranges with respect to the inlet 14 when tilted to one side or the other side.

[0162] Figure 6 is a position-time graph showing the immersion of the front end of an optical core wire during the application of an exemplary measurement profile. The x-axis represents time and the y-axis represents the position of the front end. The position of the surface of the molten metal bath MB S is shown for orientation. Prior to the start of the measurement, i.e., before t0, the front end is placed at a starting point called the first position p1. This may be inside the metallurgical vessel or may be in proximity to the inlet, i.e., the point where the optical core wire enters the vessel. The optical core wire is fed at a feed rate towards and into the molten metal bath to a second position p2 over the time from t0 to t2. The length of this time is typically within the range of a few seconds. The front end of the optical core wire enters the molten metal bath at time t1, i.e., t1 is the time when the front end is immersed below the surface of the molten metal bath. In the graph shown, a single feed rate is applied, but the feed may include several stages with different feed rates. A non-feeding stage, i.e., a stationary stage, can be included during the measurement as shown in the graph of Figure 7 representing another preferred embodiment. Temperature measurement values are acquired during the measurement time from t1 to t2. To obtain reliable measurement values, the front end must be immersed below the surface of the molten metal bath. It has been found that the most accurate results are obtained by providing the front end at a constant immersion depth at this point. The temperature values obtained in the initial stage of the feed often do not represent the bulk temperature of the molten metal bath. After t2, the optical core wire is retracted from the molten metal bath and returned to a position above the surface. Ideally, the portion of the optical core wire immersed below the surface of the molten metal bath L C is consumed by t2.

[0163] For certain reasons, it is advantageous to adjust the parameters of the feed system according to the physical configuration of the metallurgical vessel, which affects the relationship between the surface level of the molten metal bath, the position of the front end of the optical core wire at which the measurement sequence is initiated, and the reach position of the front end of the optical core wire for obtaining the measured values.

[0164] By applying the method according to the invention, the immersion depth can be selected such that the optical core wire is immersed below the surface of the molten metal bath and thus the amount consumed is minimized. Therefore, the amount of the optical core wire consumed during the measurement sequence can be further minimized.

[0165] It has been observed that various parameters applied to obtain temperature values during the application of the measurement profile result in various measurement qualities. The measurement quality of the measurement profile refers to different measurement accuracies compared to the measured values obtained using a fixedly installed standard thermocouple. The concept underlying the present invention is the adaptation of a specific measurement profile to the situation existing in the metallurgical vessel at the time when the measurement is made.

[0166] FIG. 8 is a schematic view of a system 30 according to an embodiment of the present invention. The system 30 is configured to execute the method according to the present invention. In particular, it is configured to provide a data set that associates data regarding the furnace tilt with a measurement profile that provides an optimal measurement quality for each configuration of the furnace. The system 30 is further configured to determine the configuration of the furnace, i.e., the tilt value. In addition, the system 30 is configured to select a measurement profile from the provided data set. Furthermore, the system 30 is configured to apply this measurement profile to obtain the temperature.

[0167] The system comprises an apparatus 40, which includes an optical core wire and a detector. Furthermore, the system comprises a module 50. The apparatus 40 and the module 50 are adapted to interact with each other. That is, the module is configured to execute the method according to the present invention using the apparatus 40, resulting in the measurement of the temperature value of the molten metal bath.

[0168] Figure 9 shows the schematic diagram of module 50 in more detail. Module 50 includes a memory unit S, a processing unit P, and a control unit C.

Description of symbols

[0169] 1, 1‘, 1‘‘, 1‘‘‘ optical core wire 2‘, 2‘‘, 2‘‘‘ optical fiber 3‘, 3‘‘, 3‘‘‘ metal tube 4‘‘, 4‘‘‘ second metal tube 5‘‘, 5‘‘‘ gap between metal tubes 6 equipment 7 molten metal bath 8 coil 9 opposite end (end of the core wire connected to the detector) 10 detector 110, 110’, 110’’, 110’’’ furnace 11, 11’, 11’’ container; metallurgical container 12 moving means 13 guide tube 14 entrance 15 front end of the optical core wire MBS surface of the molten metal bath 17 slag layer 18 blowing lance 19 part of the core wire immersed in the molten metal bath 20 part of the core wire exposed to the high-temperature atmosphere and slag 22 removable lid 23 electrode 24 platform 30 system 40 device 50 module S memory unit P processing unit C control unit LC length of the optical core wire immersed in the molten metal bath LD length of the optical core wire located inside the container Total length of the optical core wire fed into the LT container p1 Initial position of the front end of the optical core wire p2 Reaching position where the front end of the optical core wire is fed below the surface of the molten metal bath AP Pivot axis AT Tilting axis PH Horizontal plane

Claims

1. A method for measuring the temperature of a molten metal bath in a furnace using a device comprising an optical core wire and a detector, wherein the furnace has a furnace tilt, the furnace tilt indicating the degree to which the furnace tilts, and the tilt being defined with respect to a pivot axis A P and the method comprises: (a) providing a data set associating a furnace tilt value FI with a corresponding measurement profile MP; (b) determining a furnace tilt value FI(n) at a time point t(n); (c) selecting a measurement profile MP(n) corresponding to the furnace tilt value FI(n) from the provided data set associating the furnace tilt value FI with the corresponding measurement profile MP; (d) applying the measurement profile MP(n) at the time point t(n) to obtain a measured temperature value; and the measurement profile MP defines at least one step of providing a front end of the optical core wire at a first position p1 above the surface of the molten metal bath and at least one step of sending the front end of the optical core wire from the first position p1 towards the molten metal bath to a second position p2, the data set associates the definition of at least one parameter in at least one step of the measurement profile MP with the furnace tilt value FI, the parameter being the position and velocity of the front end of the optical core wire defined in at least one step as defined in the measurement profile MP, and the time point, and the step (c) of selecting the measurement profile MP(n) positions the front end of the optical core wire at a certain depth below the surface of the molten metal bath.

2. The method according to claim 1, wherein the second position p2 is at an immersion depth i1 below the surface of the molten metal bath.

3. The method according to claim 1 or 2, wherein the distance between the first position p1 and the second position p2 in the measurement profile MP(n) is related to the furnace tilt value FI(n).

4. The distance between the first position p1 and the second position p2 is adjusted by the same length for each inclination of the furnace in the first direction and the second direction from a predetermined initial position, according to any one of claims 1 to 3.

5. The distance between the first position p1 and the second position p2 is adjusted by a first length for each inclination of the furnace in the first direction from a predetermined initial position, and is adjusted by a second length for each inclination of the furnace in the second direction, according to any one of claims 1 to 3.

6. The distance between the first position p1 and the second position p2 is adjusted by 2 cm to 20 cm, preferably 5 cm to 15 cm, and most preferably 8 cm to 12 cm for each inclination of the furnace from a predetermined initial position, according to any one of claims 1 to 5.

7. The measurement profile MP defines at least one process during the stationary time within two time points t0 and t2, during which the feed of the front end of the optical core wire is temporarily stopped, or the front end of the optical core wire is fed at a low speed, according to any one of claims 1 to 6.

8. The measurement profile MP defines at least one process for acquiring temperature information during the measurement time within two time points t0 and t2, according to any one of claims 1 to 7.

9. The measurement profile MP defines at least one feed speed v at which the front end of the optical core wire is fed from the first position p1 towards the molten metal bath to the second position p2 fed according to any one of claims 1 to 8.

10. The dataset provided in step (a) further associates the level of the surface of the molten metal bath with the measurement profile MP, according to any one of claims 1 to 9.

11. The method according to any one of claims 1 to 10, wherein the dataset provided in step (a) further associates the position of the front end of the optical core wire with the measurement profile MP.

12. A system for determining the temperature value of a molten metal bath in a furnace, the furnace having a furnace tilt, the furnace tilt indicating the degree to which the furnace tilts, the tilt being defined with respect to a pivot axis A P The system comprises a device and a module, the module being adapted to interact with the device, the device including an optical core wire and a detector, The module includes a storage unit S, a processing unit P, and a control unit C, and the storage unit S - A storage element S1 for providing a dataset associating a furnace tilt value FI with a corresponding measurement profile MP including The measurement profile MP defines at least one step of providing the front end of the optical core wire at a first position p1 above the surface of the molten metal bath, and at least one step of sending the front end of the optical core wire from the first position p1 to a second position p2 towards the molten metal bath, The dataset associates the definition of at least one parameter in at least one step of the measurement profile MP with the furnace tilt value FI, the parameter being the position, velocity, and time point of the front end of the optical core wire defined in at least one step as defined in the measurement profile MP, The processing unit P - A processing element P1 for determining a furnace tilt value FI, - A processing element P2 for selecting a measurement profile MP(n) corresponding to the furnace tilt value FI(n) from the provided dataset associating the furnace tilt value FI with the corresponding measurement profile MP, including By the processing element P2 that selects the measurement profile MP(n), the front end of the optical core wire is positioned at a certain depth below the surface of the molten metal bath, The control unit C - A control element C1 for obtaining a measured temperature value by applying the measurement profile MP(n) A system comprising the same.

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