Weight measuring device, automated system for controlling the introduction of charge material into a furnace, apparatus using said system, and corresponding method - Patents.com

Abstract

1. An apparatus for measuring the weight of charge material fed into an electric arc furnace, comprising a plurality of supports each having an upper plate, a lower plate, and a weight measuring element disposed between and in contact with the two plates, at least one of the weight measuring elements being a column-type load cell, each of the supports having two connection elements perpendicular to each other, each connection element having a tie rod, the tie rods connected to at least one upper terminal connected to the upper plate and at least one lower terminal connected to the lower plate.

Description

[Technical field]

[0001] The embodiments described herein relate to a gravimetric measuring device, an automated system for controlling the introduction of charge material into a melting furnace using the gravimetric measuring device, an apparatus using the system, and a method for controlling the introduction of charge into a melting furnace using the apparatus.

[0002] The weight measuring device which is the subject of the present invention is used to measure the weight of a furnace, its contents and all the elements installed in said furnace, in particular but not exclusively, during the progress of the introduction of charge material into a melting furnace using a continuous charge system.

[0003] The control system is used to control the operating parameters in the melting furnace of the metal charge using information and signals coming from the weighing device provided on the furnace itself.

[0004] The above-mentioned weighing devices, control systems, devices and methods can be suitably used in the steel industry in the production of steel and other metals, or in the production of glass materials, including, but not limited to, electric arc furnaces, ladle furnaces, submerged arc furnaces, melting furnaces, smelting furnaces, induction melting furnaces, or induction heating furnaces. [Background technology]

[0005] Plants for converting and melting metallic materials are known which comprise an electric arc furnace arranged to cooperate with a system for feeding the charge material, which can be continuous, for example with a conveyor belt, or discontinuous, for example with baskets. The electric furnace comprises at least one vessel or shell, which is covered by a roof, through which holes the electrodes for starting and maintaining the melting of the charge material are introduced.

[0006] It is also known to use gravimetric measurement systems to obtain information used in controlling the operating parameters of the furnace operation, such gravimetric measurement systems being of the direct or indirect type, the latter for example based on measuring the level of a liquid bath.

[0007] Systems are known which periodically weigh the furnace to detect the amount of steel contained therein, and which also measure the temperature of the liquid bath substantially continuously, and which gravimetrically detect the rate at which charge material is discharged from the furnace and adjust the discharge rate to maintain the temperature of the liquid bath being formed constant near a predetermined target value.

[0008] Systems and methods are also known that use measurements of the weight of the furnace and the charge material introduced into the furnace to determine the rate at which a charge is introduced into the furnace.

[0009] Furthermore, systems are known in which the device for carrying out the weighing of a furnace also serves as a support for said furnace or for a structure supporting said furnace.

[0010] One drawback of the prior art is that such weighing devices must be able to withstand significant weight and therefore significant mechanical stress.

[0011] Another drawback of the prior art is that the significant weight and mechanical stresses described above tend to limit the accuracy of the data provided by the weighing devices.

[0012] JPH1032575 describes a weight measuring device equipped with a load cell that can be used in food plants, water treatment plants or tanks.

[0013] It is therefore an object of the present invention to provide an optimized weighing device, system, apparatus and method that provides improved, more reliable and more accurate weight measurement results.

[0014] Another object of the present invention is to provide more efficient control of the furnace charge and maximize the energy contribution delivered to the furnace.

[0015] Another object of the present invention is to provide improved control of the level of molten metal in a furnace.

[0016] Another object of the present invention is to improve the quality of the bath of molten metal in a furnace.

[0017] Another object of the present invention is to increase the mechanical stability of the furnace itself during all steps of the melting cycle.

[0018] Applicant has conceived, tested and embodied the present invention to overcome the shortcomings of the prior art and to achieve these and other objectives and advantages. Summary of the Invention

[0019] The invention is defined in the independent claims and is characterised in that the dependent claims define further innovative features of the invention.

[0020] The present invention relates to a gravimetric measuring device, a control system, an apparatus and a method for controlling a melting process in an electric furnace.

[0021] In one aspect of the invention, a weighing device for charge material fed into a melting furnace comprises a plurality of supports, each of which comprises an upper plate, a lower plate and a weighing element disposed midway between and in contact with the two plates, the upper plate and the lower plate being arranged parallel to each other in use.

[0022] At least one of the weight measuring elements is a column-type load cell, and each of the supports has two connection elements perpendicular to each other, the connection elements being located on a plane parallel to a plane defined by the upper plate and the lower plate, and each of the connection elements has a tie rod, which is connected to at least one upper terminal connected to the upper plate and at least one lower terminal connected to the lower plate.

[0023] In one preferred solution of the present invention, the upper plate is configured to contact the furnace and the lower plate is configured to contact and be attached to a horizontal swivel base that supports the furnace.

[0024] In the present invention, the upper plate is arranged to slide against the side or bottom wall of the furnace, for example against the bottom wall of the furnace shell, and the lower plate is welded or otherwise fixed to the top surface of the horizontal swivel bed on which the furnace rests.

[0025] The number of supports is at least three, more advantageously four, and is distributed over the periphery of the bottom of the shell.

[0026] The weighing element is arranged to compress upon any change in the weight of the furnace, which may be due, for example, to the receipt of a quantity of charge material in the form of scrap metal, briquettes, sponge iron, or mixtures thereof, or due to the tapping of molten metal.

[0027] The above-described configuration of the weight measuring element, together with the provision of connecting elements to stabilise the positioning of the weight measuring element by pressing the support element into contact with the furnace and the horizontal swivel base, enables the weight measuring element of the present invention to record weight variations with excellent accuracy and sensitivity.

[0028] Each weighing element acts as a rod that is pushed under compression based on the weight fluctuations, thereby determining the relative movement of the furnace and the horizontal swivel bed.

[0029] By providing a suitable, preferably evenly and / or symmetrically distributed, plurality of supports on the periphery of the bottom of the furnace, numerical values ​​corresponding to the number of supports can be obtained, which can be compared with each other to obtain information both on the weight of the discharged material and on its distribution within the furnace itself. In this way, it may also be possible to manage the operation of the discharge means so as to prevent local accumulations and / or non-optimal distribution of the discharged charge material within the furnace.

[0030] In one solution of the present invention, a processor receives and processes information regarding a plurality of weight values ​​detected by the individual weight measuring elements, thereby adjusting the discharge speed of the charge material in the furnace, particularly when continuous discharge is performed using a belt or the like.

[0031] Knowledge of localized weight variations can also reduce the risk of material discharged into the furnace impinging on and damaging structural support elements that are at least partially present within the furnace, such as electrodes, burners, lances, tuyere, etc.

[0032] This auxiliary element has in particular the function of supplying the furnace with an additional force, for example of chemical type, in addition to the electrical power supplied by means of the electrodes.

[0033] In another aspect of the invention, the weighing element configured as described above is capable of self-adapting in the event of misalignment of the furnace base, the support and / or the platform.

[0034] Furnace leveling can be achieved by means of tie rods mounted to motorized adjustment means managed by an automatic control system.

[0035] In another embodiment of the invention, each support is provided with a cooling shell for controlling the temperature of the weight measuring element associated with it.

[0036] In another example of the invention, the cooling shell is a hollow cylindrical shell at least partially surrounding the central rod, a cooling liquid circulates within the hollow cylindrical shell, the cooling liquid being introduced into the cooling shell by an inlet nozzle and expelled from the cooling shell by an outlet nozzle.

[0037] In yet another embodiment of the invention, the at least one column-type weighing element comprises a central rod supporting at least a portion of the weight of the furnace and its contents and at least a portion of the weight of all elements installed in the furnace.

[0038] In another embodiment of the invention, the central rod is equipped with at least two strain sensors.

[0039] In another embodiment of the invention, the central rod is removably or non-removably attached to the lower plate.

[0040] Another aspect of the invention provides an automated system for controlling the introduction of charge material into an electric arc furnace, the automated system comprising a weighing device of the above type, the support being sandwiched between the furnace and a horizontal swivel bed, and a processor configured to control the amount of charge material introduced into the furnace based on weight information generated by the weighing device and in dependence on the value of energy supplied to the bath.

[0041] In one example of the invention, the value of the energy supplied to the bath corresponds to the sum of the value of the power supplied to the electrodes during the dissolution sequence and the value of the chemical power supplied by the auxiliary device.

[0042] In this way, the incremental amount of charge material introduced into the furnace always correlates accurately with the total amount of energy delivered to the furnace.

[0043] Another aspect of the invention provides an apparatus comprising an electric arc furnace, comprising an automated system as described above for controlling the introduction of charge material into said furnace.

[0044] Another aspect of the invention provides a method for controlling the input of charge material to an electric arc furnace during a melting sequence by an automatic control system, the method including the steps of: determining a plurality of weight values ​​of the furnace, its contents, and all elements installed in the furnace at a plurality of different times using the gravimetric measuring element, obtaining a total energy value delivered to the bath using the processor, and controlling, using the processor, an amount of charge material introduced into the furnace using the charge material transport element based on the total energy value and the weight values.

[0045] In one embodiment of the invention, the method includes the step of deriving the total energy value based on a value of the power supplied to the electrodes and a value of the chemical power supplied by the auxiliary device.

[0046] In another embodiment of the invention, the method includes using the processor to adjust a speed of the charge material transport means based on a weight value provided by the weight measuring device and a total energy value supplied into the furnace.

[0047] An advantage of the weighing device, system, apparatus and method is that due to the structure and configuration of the weighing device, actions for controlling the charging of the electric arc furnace are automatically performed based on very accurate weight values.

[0048] These and other aspects, features and advantages of the invention are apparent from the following description of some embodiments, given as non-limiting examples, with reference to the attached drawings, in which: [Brief description of the drawings]

[0049] [Figure 1]FIG. 1 shows an apparatus used to control the charging of an electric arc furnace, the apparatus comprising said furnace, a platform for supporting said furnace, and a system for weighing the furnace and charging the charge material. [Diagram 2] FIG. 2 is a projection view of a support for an electric arc furnace. [Diagram 3] FIG. 2 is an exploded view of a support for an electric arc furnace. [Figure 4] FIG. 2 is a cross-sectional view of a weight measuring element included in a support of an electric arc furnace. [Diagram 5] FIG. 1 is a simplified diagram of a processing section of an apparatus with an electric arc furnace. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0050] For ease of understanding, the same reference numbers have been used, where possible, in the drawings to refer to identical common elements, and it should be understood that elements or features of one embodiment may be readily combined or incorporated into other embodiments without the need for detailed description.

[0051] The present invention will now be described in detail with respect to possible embodiments, one or more examples of which are illustrated by way of non-limiting example in the accompanying drawings, in which the language and terminology used herein are also intended to be illustrative and non-limiting.

[0052] 1, the embodiment described herein relates to an apparatus 10 comprising a furnace 100, in this example an electric arc furnace 100, having a shell 110 for containing charge material 210 to be melted and / or a molten metal charge, a cover roof 120, an inlet passage 130 through which the charge material 210 is introduced into the furnace 100, and a slag discharge passage 140 through which the slag is discharged at the end of the melting process. The furnace also has a known tap, commonly referred to as EBT, at the bottom of the shell 110, which is not shown in the drawings.

[0053] The furnace 100 also includes one or more electrodes 150 inserted into the furnace 100 through the cover roof 120 and configured to provide energy to melt the charge material 210 in the shell 110 (furnace 100) to produce an electric arc between the electrodes 150 if the furnace is powered with AC power, or between the electrodes 150 and the bottom of the shell if the furnace is powered with DC power.

[0054] The one or more electrodes 150 are removably mounted in the furnace 100 so that the one or more electrodes 150 can be inserted or removed from the furnace 100 depending on process requirements and / or to prevent damage to the one or more electrodes 150 or the furnace 100. The one or more electrodes 150 are connected to a power supply system (not shown). The one or more electrodes 150 can be electrically connected or disconnected from the power supply system based on the process or safety considerations during various steps of the charge material 210 loading, molten metal charge discharge, slag removal, or tapping process.

[0055] The power supplied to the electrodes 150 can be varied over time from a minimum power until it reaches operating power by increasing the power supplied to the electrode(s) 150 depending on the amount of charge material 210 and / or bath 200 present in the furnace 100.

[0056] Furnace 100 further includes auxiliary elements (not shown) such as burners, oxygen lances, pulverized coal injectors, and similar elements that can enhance the melting process within furnace 100 by providing additional energy, primarily from chemical-type reactions.

[0057] The apparatus 10 further includes a horizontal swivel platform 160, a moving element 180 for tilting the horizontal swivel platform 160, and a weight measurement system or device including a plurality of supports 170 sandwiched between the horizontal swivel platform 160 and the furnace 100.

[0058] 1, the moving element 180 is shown as a roller sandwiched between the horizontal swivel platform 160 and a base platform 190 resting on the ground / floor. It will be apparent to one skilled in the art that the moving element 180 can be made of any element capable of tilting the horizontal swivel platform 160 to a particular angle relative to the horizontal, and is not limited to the rollers shown in FIG.

[0059] The furnace 100 is mechanically connected to the horizontal swivel base 160 by supports 170, which cause the furnace 100 to tilt whenever the horizontal swivel base 160 tilts.

[0060] During operation of the furnace, ie, during the melting sequence, the horizontal swivel base 160 is oscillated by the moving means 180 at an angle of approximately -5 to +5 degrees relative to the horizontal, thereby oscillating the furnace 100 at an angle of approximately -5 to +5 degrees relative to the horizontal.

[0061] Optionally, the moving means 180 tilts the horizontal swivel platform 160 at an angle of approximately -1 to -15 degrees relative to the horizontal during the slag removal step, thereby tilting the furnace 100 at an angle of approximately -1 to -15 degrees relative to the horizontal.

[0062] Optionally, the moving means 180 tilts the horizontal swivel platform 160 at an angle of approximately +5 to +20 degrees relative to the horizontal during the tapping step, thereby tilting the furnace 100 at an angle of approximately +5 to +20 degrees relative to the horizontal.

[0063] If the charge material 210 is being charged in a discontinuous manner, such as by using one or more baskets to discharge the charge material 210 into the furnace 100, at least a portion of the roof 120 is opened or removed and the electrodes 150 are removed and disconnected from the power supply.

[0064] The charge material 210 may be charged in a continuous manner using a transport 135, such as a conveyor belt disposed in a preheat tunnel, that continuously discharges the charge material 210 into the furnace 100.

[0065] Continuous and discontinuous modes of processing for charging the charge material 210 into the furnace 100 can be combined in series or in parallel. In particular, a discontinuous charging mode can be used to initiate a melting sequence, during which the discontinuous charging mode can be replaced by a continuous mode based on considerations regarding the temperature in the furnace 100 or the power supplied to the electrodes 150, or based on considerations regarding the total energy supplied to the charge material 210 or bath 200 contained in the furnace 100.

[0066] With such a continuous charging scheme, the charge material 210 may be continuously discharged into the furnace 100 during the melting sequence, interrupted only during the slag removal step or tapping of the molten material.

[0067] In the present invention, the furnace 100 is placed on the horizontal swivel base 160 by a weighing device, which comprises a number of supports 170 arranged along the lower periphery of the furnace 100 or shell 110, and the supports 170 are sandwiched between the furnace 100 and the horizontal swivel base 160. The majority of the furnace 100 rests on the supports 170, and the weight of the furnace 100 is rested on the horizontal swivel base 160 only by the supports 170. Preferably, the number of supports 170 is at least three. It is clear to a person skilled in the art that the number of supports is not limited to the number shown in FIG. 1, and that the supports of the present invention can be more than three, without compromising the field of protection.

[0068] Each support 170 comprises one or more weighing elements 171 and two connecting elements 173 that allow the furnace 100 to be mechanically connected to the horizontal swivel base 160. At least one of the weighing elements 171 is a column-type load cell that comprises a central rod 171a that supports the weight of the furnace, its contents, and all elements installed in the furnace 100.

[0069] The central rod 171a is equipped with at least two strain sensors (not shown) that are capable of detecting strain in the central rod 171a caused by compression along the vertical axis or compression having a component along the vertical axis, in other words, strain in the central rod 171a caused by fluctuations in the weight applied to the rod 171a.

[0070] Optionally, the temperature of the weight measuring element 171 or each weight measuring element 171 is controlled by a cooling shell 177 .

[0071] The two connecting elements 173 are perpendicular to each other, thereby constraining the movement of the furnace 100 and the horizontal swivel base 160 in two axes.

[0072] 2 and 3, each support 170 includes a weighing element 171 sandwiched between an upper plate 172a and a lower plate 172b. The upper plate 172a of the support 170 is configured to contact the lower surface 100a of the furnace 100, while the lower plate 172b is configured to contact the upper surface 160a of the horizontal swivel bed 160.

[0073] Those skilled in the art will appreciate that the top plate 172 a of the support 170 can also contact the side 100 b of the furnace 100 or the side 100 b of the shell 110 .

[0074] The attachment of the lower plate 172b of the support 170 to the upper surface 160a of the horizontal swivel base 160 may be by means of an attachment means or may be permanently attached, such as by welding.

[0075] 1, 2 and 3, the upper plate 172a and the lower plate 172b are shown as flat plates. In use, the upper plate 172a and the lower plate 172b are disposed substantially parallel to one another. One skilled in the art will appreciate that the upper plate 172a and the lower plate 172b may have any shape that matches the shape of the lower surface 100a and / or the side surface 100b of the furnace 100 and the upper surface 160a of the pedestal 160.

[0076] If the plates 172a, 172b have a non-planar shape, then the shape will necessarily ensure that the parallelism is at least partially maintained during use.

[0077] The weight measuring element 171 of the support 170 is inserted between an upper plate 172a and a lower plate 172b, which are connected to each other by means of two connecting elements 173. The two connecting elements 173 are arranged perpendicular to each other and are on a plane substantially parallel to the plane defined by the upper plate 172a and the lower plate 172b. Each connecting element 173 includes a tie rod 173c and an upper terminal 173a and a lower terminal 173b arranged at the end of the tie rod 173c.

[0078] The upper terminal 173a is configured to be mechanically connected only to the upper plate 172a, and the lower terminal 173b is configured to be mechanically connected only to the lower plate 172b. In other words, the tie rod 173c is mechanically connected to the upper plate 172a by the upper terminal 173a, and is mechanically connected to the lower plate 172b by the lower terminal 173b.

[0079] The mechanical connection between the tie rod 173c and the upper terminal 173a and the lower terminal 173b is ensured by a connecting element 173d such as a joint, a hinge, a pin, etc. It is obvious to a person skilled in the art that any connecting element that can mechanically connect two mechanical elements and allows relative movement between the two elements can be used as the connecting element 173d in the present invention.

[0080] Threaded mounting elements (not shown) may be used to mechanically connect upper terminal 173a to upper plate 172a and lower terminal 173b to lower plate 172b. Optionally, upper terminal 173a and lower terminal 173b are permanently attached, such as by welding, to their respective plates.

[0081] The two connection elements 173 are perpendicular to each other, thereby restricting the relative movement of the upper plate 172a and the lower plate 172b in two axes. The arrangement of the two connection elements 173 in this manner can also restrict the movement of the furnace 100 on two axes to absorb or eliminate shear forces along the two axes.

[0082] Additionally, the connecting elements 173 may be used to align and / or level the furnace 100 to a predetermined position or to align and / or level the shell 110. Such adjustment, alignment and / or leveling of the furnace 100 may be accomplished using the conventional act of lengthening or shortening the length of the tie rods 173c of the connecting elements 173.

[0083] Weight measuring element 171 is sandwiched between furnace 100 and horizontal swivel base 160 and supports, i.e. measures, only the weight of top plate 172a, furnace 100, the contents of furnace 100, and all elements installed in furnace 100. The element installed in furnace 100 is, for example, electrode 150 if electrode 150 is installed in furnace 100 and its weight is applied to furnace 100.

[0084] The weight of the top plate 172a is several orders of magnitude less than the weight of the furnace 100 or any other object being weighed, and therefore the weight value of the top plate 172a can be ignored in any calculation involving weight values ​​detected by the weight measuring element 171.

[0085] One skilled in the art can determine that, when the components installed in the furnace 100 are the same, the difference between the two weight measurements of the furnace 100 can provide an indication of a change in the contents of the furnace, i.e., whether any charge material 210 has been introduced into the furnace and / or whether at least a portion of the bath 200 has been removed from the furnace 100, for example by tapping.

[0086] Optionally, each of the plurality of supports 170 comprises the same type of weight measuring element 171. In another example, at least one of the plurality of supports 170 comprises a weight measuring element 171 consisting of a column-type load cell with a central rod 171a, which is preferably permanently connected to the lower plate 172b and is configured to support the weight of the furnace 100, its contents and all elements installed in the furnace 100.

[0087] The rod 171a is provided with at least two strain sensors (not shown), as described above, optionally perpendicular to each other, capable of measuring the strain induced in the rod 171a under the influence of the weight of the furnace 100, its contents and all elements installed in the furnace 100. Optionally, the rod 171a is provided with four strain sensors, pairwise perpendicular to each other, in an electrical configuration forming a Wheatstone bridge.

[0088] The at least two strain sensors generate electrical signals based on the strain caused by the load (weight) applied to the rod 171a. The electrical signals generated by the strain sensors are sent to a processing unit 300 (only shown in FIG. 5) for processing the measured values. The processing unit includes at least a processor 310, a memory 320, and a communication unit 330 for transmitting and receiving electrical signals to and from the outside, i.e., each element of the furnace 100 or a control unit (not shown), the control unit being operable by an operator. The processor 310, the memory 320, and the communication unit 330 are connected to each other using a physical support or wirelessly, and can communicate with each other.

[0089] In the following description, reference is made to the processing unit 300 without specifying which elements perform which individual functions, as such matters are believed to be well known and commonly known in the art. Additionally, the processing unit 300 may control the power supply of the electrodes 150. Alternatively, the power supply of the electrodes 150 is controlled by a power supply (not shown) that is optionally connected to the processing unit 300.

[0090] In one embodiment of the invention, the electrical signal is sent to the processing unit 300 using at least one electrical cable 176. In another embodiment of the invention, the electrical signal is processed and sent to the processing unit 300 using a wireless connection. In another embodiment of the invention, the electrical signal generated by the strain sensor is pre-processed by a processing unit (not shown) located near the load cell and the pre-processed signal is sent to said processing unit using a physical medium, cable, wire, etc. or in a wireless mode.

[0091] Optionally, the processing unit 300 receives one signal resulting from processing of multiple signals from each strain sensor, or in another example, the processing unit 300 receives as many electrical signals as there are strain sensors, raw or pre-processed electrical signals generated by the strain sensors.

[0092] Weight measuring element 171 operates by detecting the strain of rod 171a under compression, which is proportional to the load placed on weight measuring element 171. In this manner, weight measuring element 171 is able to monitor in real time the weight of furnace 100, the contents of furnace 100, and all elements mounted or installed in furnace 100.

[0093] The support 170 is mounted in the vicinity of the furnace 100 and is therefore exposed to high temperatures generated by the melting or bath 200 of the charge material 210. To ensure that the strain sensor provided on the rod 171a does not malfunction or is not affected by any phenomena caused by the high temperatures, the weighing element 171 is provided with a cooling system comprising a cooling shell 177 at least partially surrounding the rod 171a.

[0094] The cooling shell 177 is a substantially hollow cylindrical shell or a portion thereof. A cooling liquid 177c (optionally water) can be circulated within the cooling shell 177 to control the temperature of the rod 171a. The cooling liquid is introduced into the cooling shell 177 through an inlet nozzle 177a and exits the cooling shell 177 through an outlet nozzle 177b. The inlet nozzle 177a and the outlet nozzle 177b are formed on the outer surface of the cooling shell 177, and each nozzle can be connected to a conduit (not shown) through which the cooling liquid can flow and a conduit through which the cooling liquid can flow out.

[0095] The cooling liquid 177c discharged from the cooling shell 177 by the outlet nozzle 177b is cooled by a cooling unit (not shown) and reintroduced into the cooling shell 177 at an appropriate temperature by the inlet nozzle 177a. Optionally, each cooling shell 177 is connected to a cooling unit. Alternatively, the cooling shells 177 of all the weight measuring elements 171 are connected to one cooling unit.

[0096] By controlling the temperature of the weight measuring element 171, the effect of temperature on the weight measurements of the furnace 100, its contents, and all elements installed in the furnace 100 can be minimized or eliminated.

[0097] Data regarding the furnace 100, its contents, and the weight of all elements installed in the furnace 100 is used by the processor 300 to determine the amount of charge material 210 to be introduced into the furnace 100. The charge material 210 is transported and introduced into the furnace by a transport means 135, which transports the charge material 210 from outside the furnace 100 to the inlet channel 130 and then into the furnace 100. For example, the transport means 135 can be a conveyor belt, but it will be apparent to one skilled in the art that any means of transportation capable of introducing the charge material 210 into the furnace 100 can be used without detracting from the objectives of the present invention.

[0098] The transport means 135 is connected to the processing unit 300, which controls the introduction of the charge material 210 in the furnace by controlling the movement of said transport means 135 based on instructions pre-set by an operator or based on instructions pre-recorded in the memory of the processing unit 300. In one example of the invention, the processing unit 300 controls the movement of the transport means 135 based on data received from sensors, such as for example a strain sensor of the weighing element 171 or a temperature detection sensor (not shown) measuring temperature values ​​in the furnace and / or its contents, or based on operating parameters, such as for example the power supplied to the electrodes 150.

[0099] In one example of the present invention, at least one of the following values ​​detected by sensors not shown is used to obtain the value of the total energy supplied to the charge material 210 or bath 200 present in the furnace 100, such values ​​being, for example, the temperature value of the interior and / or contents of the furnace 100, the chemical detection sensor value, the pressure value, the value of the power supplied to the electrode 150, and the value of the chemical force resulting from the reaction occurring in the furnace.

[0100] Optionally, the value of the total energy supplied to the charge material 210 or bath 200 considers both the value of the power supplied to the electrode 150 and the chemical forces generated by reactions caused by the introduction of solid or gaseous substances using the auxiliary elements described above.

[0101] In another example of the present invention, the total energy value obtained from the processing unit 300 is combined with a weight value measured by at least one of the multiple weight measuring elements 171 and transmitted to the processing unit 300 to determine how to adjust the amount of charge material 210 introduced into the furnace 100 based on the force supplied within the furnace.

[0102] To control the amount of charge material 210 introduced into the furnace 100 , the processor 300 controls the transport means 135 to supply additional charge material 210 and / or stop / slow down the introduction of the charge material 210 into the furnace 100 .

[0103] Furthermore, by arranging at least three supports 170 on the periphery of the furnace 100, the distribution of the weight of the charge material 210 in the furnace 100 can be determined. In this case, the weight values ​​detected by the weight measuring elements 171 of the supports 170 are processed by the processing unit 300 to determine the geometric distribution of the weight of the contents of the furnace 100. The processing unit 300 can also determine said geometric distribution based on data on the inclination of the furnace 100 relative to the horizontal direction, taking into account the displacement of the contents of the furnace 100 when the furnace 100 is tilted by the horizontal swivel 160.

[0104] In one example of the present invention, data regarding the distribution of the weight of the charge material is used by the processing unit 300, alone or in combination with the above data, to determine not only the amount of charge material 210 to be added to the furnace 100, but also the distribution of the charge material 210 and / or bath 200 within the furnace 100.

[0105] Optionally, the processor 300 also controls the direction in which the charge material 210 is discharged by the transport means 135 based on the data of the distribution of the charge material 210 .

[0106] Data regarding the distribution of the weight of charge material 210 can be used by processor 300 to prevent non-optimal buildup and / or distribution of charge material 210 that can affect melting efficiency, which is the amount of energy used to melt charge material 210 and / or to maintain or complete the melting of bath 200, and the time required to achieve melting of charge material 210. Additionally, this can prevent charge material 210 from being mispositioned within furnace 100 or from contacting or colliding with sensitive structures and / or components located within the furnace, such as electrodes 150, burners, lances, tuyere, etc.

[0107] Optionally, weighing of the furnace 100, its contents, and all elements installed in the furnace 100 is repeated periodically over a period of time. By examining the trend in weight values ​​measured at different times, the amount of bath 200 contained within the furnace can be determined.

[0108] Assuming that the weight of the furnace 100 and all the elements installed in the furnace 100 are values ​​that do not vary over time, the difference between the weight values ​​obtained from the weight measuring element 171 depends only on how much charge material 210 has been introduced into the furnace or how much bath 200 has been removed from the furnace 100. This is especially true when the weight measurements are taken at time intervals that are short compared to the period during which the furnace 100 can be continuously used without any restoration or maintenance work being performed on the furnace 100.

[0109] Over an extended period of time, the difference between two weight measurements of the furnace 100, its contents or any element installed in the furnace 100, can provide data on the wear of the furnace 100, in particular on the wear of the inner walls of the furnace 100, or can also provide data on the presence of accumulated slag, which can in particular identify the start of the above-mentioned restoration or maintenance process.

[0110] In the embodiment described above, the processor 300 and support 170 form an automated system for controlling and determining the introduction of charge material 210 into the furnace 100 .

[0111] The purpose of the parenthetical signs in the accompanying claims is only to facilitate reading, and such parentheses shall not be considered as a limiting factor on the scope of protection recited in a particular claim.

Claims

1. A weight measuring device for measuring the weight of a charge material (210) introduced into an electric arc furnace (100) mounted on a horizontal rotating platform (160), comprising: a plurality of supports (170); Each of the supports (170) comprises an upper plate (172a), a lower plate (172b) and a weight measuring element (171) arranged midway between the two plates (172a, 172b) and in contact with the two plates (172a, 172b); In use, the upper plate (172a) and the lower plate (172b) are arranged parallel to each other; The weight measuring element (171) is a column-type load cell; Each of said supports (170) comprises two connecting elements (173) perpendicular to each other, the connecting element (173) lies in a plane parallel to a plane defined by the upper plate (172a) and the lower plate (172b); Each of the connection elements (173) includes a tie rod (173c), The tie rod (173c) is connected to at least one upper terminal (173a) connected to the upper plate (172a) and at least one lower terminal (173b) connected to the lower plate (172b). A weight measuring device comprising:

2. the top plate (172a) is configured to contact the furnace (100); the lower plate (172b) is configured to contact the horizontal swivel (160) that supports the furnace; The weight measuring device according to claim 1.

3. At least three of the supports (170) are evenly distributed among one another; 3. The weight measuring device according to claim 1 or 2.

4. Each of the supports (170) is provided with a cooling shell (177) for controlling the temperature of the weight measuring element (171) provided thereto.

4. A weight measuring device according to claim 1.

5. said at least one weighing element (171) comprises a central rod (171a) for supporting at least a part of the weight of said furnace (100) and its contents and at least a part of the weight of all elements installed in said furnace (100); 5. A weight measuring device according to claim 1.

6. The central rod (171a) is equipped with at least two strain sensors.

6. The weight measuring device according to claim 5.

7. The central rod (171a) is attached to the lower plate (172b).

7. The weight measuring device according to claim 5 or 6.

8. The cooling shell (177) is a hollow cylindrical shell that at least partially surrounds the central rod (171a); A cooling fluid (177c) circulates within the hollow cylindrical shell; The cooling liquid (177c) is introduced into the cooling shell (177) by an inlet nozzle (177a) and discharged from the cooling shell (177) by an outlet nozzle (177b). A weight measuring device according to claim 5 which recites claim 4.

9. 1. An automated system for controlling the introduction of a charge material (210) into an electric arc furnace (100) equipped with an electrode (150), comprising:

10. A weighing device according to claim 1, configured to weigh the furnace (100), its contents and all elements installed in the furnace (100), wherein the support (170) of the plurality of supports (170) is sandwiched between the furnace (100) and a horizontal swivel (160); a processing unit (300) configured to control the amount of charge material (210) introduced into the furnace (100) depending on the value of the energy supplied in the furnace based on information received from the weight measuring device; An automated system comprising:

10. the value of the energy supplied in the furnace (100) corresponds to a combination of the value of the power supplied to the electrodes (150) during the melting sequence and the value of the chemical power supplied to the molten metal charge bath (200) produced by auxiliary elements such as electrodes, burners, lances or tuyere; 10. The automated system of claim 9.

11. An apparatus (10) comprising an electric arc furnace (100), 11. Apparatus (10), characterized in that it comprises an automatic system according to claim 9 or 10 for controlling the introduction of charge material (210) into the furnace (100).

12. The support (170) is disposed along the periphery of the furnace (100). The device (10) of claim 11.

13. a transport element (135) for transporting and introducing the charge material (210) into the furnace (100); 13. Apparatus (10) according to claim 11 or 12.

14. 11. A method for controlling the input of charge material (210) into an electric arc furnace (100) during a melting sequence by an automatic control system according to claim 9 or 10, comprising: determining, at different times using the weighing element (171), a number of weight values ​​of the furnace (100), the contents of the furnace (100) and all elements installed in the furnace (100); obtaining, using said processing unit (300), a total energy value supplied to the bath (200) formed by said charge material in solution; using the processor (300) to control an amount of charge material (210) introduced into the furnace (100) using a charge material (210) transport element (135) based on the total energy value and the weight value; The method according to claim 1, further comprising:

15. obtaining a total energy value supplied to the bath (200) comprises obtaining said total energy value based on a value of the power supplied to one or more electrodes (150) during the melting sequence and on a value of the chemical power generated by auxiliary elements such as electrodes, burners, lances or tuyere, The control method according to claim 14.

16. controlling the amount of charge material (210) introduced into the furnace (100) includes controlling the speed of the transport element (135), which is a conveyor belt, using the processor (300); 16. The control method according to claim 14 or 15.

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