JP6070766B2 - Allocation plan creation method and allocation plan creation device for molten steel pan - Google Patents

Description

  The present invention relates to an allocation plan creation method and an allocation plan creation device for a molten steel pan that allocates a molten steel pan required for molten steel processing in a steelmaking factory to the outgoing steel charge.

  In the molten steel treatment in the steelmaking factory, the molten steel discharged from the converter is poured into a molten steel pan whose inner wall surface is covered with a refractory and adjusted to the desired components and temperature in the secondary refining equipment, It is poured from a molten steel pan into a continuous casting facility and cast into intermediate products such as slabs and billets. And the molten steel pan from which the molten steel was emptied is maintained and then transported to the converter again, and the same operation is repeated.

  In such molten steel processing, the molten steel pan can be used continuously as long as the lead time from the molten steel to the casting, that is, the time that the molten steel pan is occupied is the same for each of the outgoing steel charges. It is possible to easily grasp the number of molten steel pans necessary for the operation and which molten steel pan is allocated. Note that the steel output charge means a batch process in which blowing in the converter is a unit, in other words, molten steel that is output from the converter in a single steel output process.

  However, in actual molten steel processing, in order to produce a wide variety of steel products, the processing content in the secondary refining equipment and continuous casting equipment varies depending on the steel output charge. Therefore, the time required for molten steel to pass through the secondary refining equipment and continuous casting equipment varies depending on the steel output charge, and the lead time from the molten steel to the casting varies depending on the steel output charge. Therefore, for example, it was difficult to grasp the number of molten steel pans required per day and which molten steel pans can be allocated.

  In addition, the molten steel pan (empty pan) after emptying the molten steel needs to be quickly applied to the next steel charging while keeping the temperature as high as possible. This is because the higher the temperature of the molten steel pan that is allocated, the lower the steel output temperature, and it can be expected to reduce energy in the converter, extend the life of the converter, and the like.

  Therefore, a technique for efficiently allocating a molten steel pan to molten steel processing according to a steel production plan after satisfying these conditions is disclosed.

  For example, Patent Document 1 discloses a technique for assigning a molten steel pan to a steel output charge by a genetic algorithm. According to this method, the next steel charge can be applied in a short time after the molten steel pan is emptied.

  Further, Patent Documents 2 to 4 disclose a technique for attracting a molten steel pan to a steel output charge by heuristics. According to this method, the next steel charge can be applied in a short time after the molten steel pan is emptied.

Japanese Patent Laid-Open No. 10-143567 JP 2012-92400 A JP 2012-123772 A JP 2012-173838 A

  However, the genetic algorithm described in Patent Document 1 requires adjustment of parameters such as crossover and mutation location and occurrence probability, and whether or not an optimal solution exceeding a desired level can be obtained is determined by this parameter. It depends on the adjustment. In addition, in the techniques described in Patent Documents 2 to 4, it is only necessary to derive one feasible solution by repeating the operation of selecting a molten steel pan that can be allocated in the order of the steel start time, and the feasible solution is the optimal solution. That's not true.

  The present invention has been made in view of the above-described problems, and can efficiently allocate a molten steel pan to a molten steel treatment according to a steelmaking plan without requiring adjustment of parameters that determine the level of an optimal solution. It is an object of the present invention to provide an allocation plan creation method and an allocation plan creation device for a molten steel pan.

  In order to solve the above-mentioned problems and achieve the object, the method for preparing the allocation plan for molten steel pans according to the present invention associates the ladle numbers of the molten steel pans to be allocated to each of the outgoing steel charges arranged in the order of the outgoing steel start times. Is an allocation plan creation method for a molten steel ladle that creates the allocation arrangement as an allocation plan, and selects a steelmaking charge that has the earliest steeling start time among the steelmaking charges that have not yet been associated with the molten steel ladle number. Select one of the selection step and the allocation arrangement of a predetermined number or less that has not yet been associated with the ladle number of the ladle to be allocated to all or part of the steel bill charges arranged in the order of the steel mill start time. Allocation sequence selection step to be added, and the allocation sequence selected in the allocation sequence selection step are added to the allocation sequence and allocated to the outgoing steel charge selected in the outgoing steel charge selection step. An information update step of replacing each of the ladle numbers of one or more active ladles with one or more allocation arrays corresponding to each other, and updating information on the use history of each ladle of each replaced allocation array, When all of the allocation arrangements are selected in the allocation arrangement selection step and the processing of the information update step for each of the allocation arrangements selected is completed, a predetermined evaluation is performed on each of the allocation arrangements that are replaced. Adopting step of adopting a predetermined number or less of the allocation arrangement, and all of the outgoing steel charges are selected in the outgoing steel charge selecting step, and the allocation arrangement selecting step, the information updating step and the adopting for each selected outgoing steel charge When the processing of the step is finished, a predetermined number for each of the provision arrangements of the predetermined number or less adopted is used. Performing valence, and wherein the most or Rated high reserve sequences selected as provision plan, or containing, a provision planning step of a plurality selected from high allowance sequence evaluation.

  In order to solve the above-mentioned problems and achieve the object, the apparatus for creating an allocation plan for molten steel pans according to the present invention associates the ladle numbers of the molten steel pans assigned to each of the outgoing steel charges arranged in the order of the outgoing steel start times. Is a molten steel allocation plan creation device that creates the allocation arrangement as a provision plan, and selects a steelmaking charge that has the earliest steeling start time among the steelmaking charges that have not yet been associated with the molten steel ladle number. Select one of the selection arrangement and the allocation arrangement of a predetermined number or less that has not yet been associated with the ladle numbers of the ladle to be allocated to all or a part of the steel charging charges arranged in the order of the steelmaking start time. The allocation arrangement selecting means to be added, and the allocation arrangement selected by the allocation arrangement selection means can be added to the allocation arrangement and allocated to the outgoing steel charge selected by the outgoing steel charge selection means. Information updating means for replacing each of the molten steel ladle numbers of the upper ladle with one or more allocation arrays associated with each other, and updating information regarding the usage history of each molten ladle of each replaced allocation array, and the allocation array selection When all the allocation arrays are selected by the means and the processing by the information updating unit for each selected allocation array is completed, a predetermined evaluation is performed on each replaced allocation array, and the predetermined number or less is ordered in descending order of evaluation. All of the outgoing steel charges are selected by the adoption means adopting the allocation arrangement, and the allocation arrangement selecting means, the information updating means, and the adoption means for each selected outgoing steel charge. Is completed, a predetermined evaluation is performed on each of the adopted allocation arrays of the predetermined number or less, and the allocation array having the highest evaluation is used. Select the provision plan, or the provision planning means for a plurality selected from high allowance sequence evaluation, characterized in that it comprises a.

  According to the allocation plan creation method and the allocation plan creation apparatus of the molten steel pan according to the present invention, the molten steel pan is efficiently allocated to the molten steel processing according to the steel production plan without requiring adjustment of parameters that influence the level of the optimal solution. be able to.

FIG. 1 is a schematic diagram for explaining the flow of molten steel processing. FIG. 2 is a block diagram showing a configuration of an allocation plan creation apparatus that is an embodiment of the present invention. FIG. 3 is a diagram illustrating the structure of the steel output charge data according to the present embodiment. FIG. 4 is a diagram illustrating a configuration of molten steel pan data according to the present embodiment. FIG. 5 is a diagram illustrating a configuration of exchange time data according to the present embodiment. FIG. 6 is a flowchart showing the allocation plan creation processing procedure of the present embodiment. FIG. 7 is a diagram for explaining a fixed allocation array according to the present embodiment. FIG. 8 is a diagram for explaining an allocation plan creation process according to the present embodiment. FIG. 9 is a diagram illustrating an allocation plan created according to the present embodiment. FIG. 10A is a diagram for explaining the constraint condition of the present embodiment. FIG. 10B is a diagram for explaining the constraint condition of the present embodiment. FIG. 11A is a diagram for explaining the constraint condition of the present embodiment. FIG. 11B is a diagram for explaining the constraint condition of the present embodiment. FIG. 12A is a diagram for explaining the constraint condition of the present embodiment. FIG. 12B is a diagram for explaining the constraint condition of the present embodiment. FIG. 13 is a diagram illustrating an allocation plan created by an operator. FIG. 14 is a diagram illustrating an allocation plan created and selected according to the present embodiment. FIG. 15 is a diagram illustrating an empty pan time distribution in the present embodiment.

  Hereinafter, with reference to the drawings, a method for creating a steelmaking reserve plan for a ladle and an apparatus for creating a steelmaking reserve according to an embodiment of the present invention will be described. In addition, this invention is not limited by this embodiment. Moreover, in description of drawing, the same code | symbol is attached | subjected and shown to the same part.

[Flow of molten steel treatment]
First, with reference to FIG. 1, the flow of the molten steel process used as the process object of the allocation plan preparation method and allocation plan preparation apparatus of the molten steel pan which are one Embodiment of this invention is demonstrated.

  FIG. 1 is a schematic diagram for explaining the flow of molten steel processing. In FIG. 1, only the main steps are shown in order to simplify the description. As shown in FIG. 1, in the molten steel process in a steelmaking factory, first, the molten steel 2 discharged from the converter 1 is poured into a molten steel pan 3 whose inner wall surface is covered with a refractory. Next, the molten steel 2 poured into the molten steel pan 3 is adjusted to a target component and temperature in the secondary refining equipment (secondary refining). Specifically, in the secondary refining equipment, additives such as alloy iron and chemicals for component adjustment are added to the molten steel 2 through the introduction pipe 4 in accordance with the steel output components and specifications. Next, the molten steel 2 adjusted to the target component and temperature is transported to the continuous casting facility 5 in a state where it is put in the molten steel pan 3 and poured into the continuous casting facility 5 to produce intermediate products such as slabs and billets. Casting (continuous casting). After the molten steel 2 is emptied, the molten steel pan 3 is again put into the converter 1 after the inner wall is cured and the plate 6, the nozzle 7 and the porous 8 are maintained / replaced (empty pan maintenance). The same operation is repeated.

  In addition, each part of the plate 6 of the molten steel pan 3, the nozzle 7, or the porous 8 is replaced | exchanged whenever it uses each predetermined number of times. When replacing these parts of the plate 6, the nozzle 7, or the porous 8, after the casting is finished and the molten steel 2 is emptied, the molten steel pan 3 can be used for the next steel charging. Maintenance time is required. During this maintenance time, it is necessary to confirm the change in the bottom of the molten steel pan, remove clogs in the nozzle 7, insert sand to cover the nozzle 7, etc. In addition to the transfer time required for the above, a part replacement time that differs for each part is included.

[Configuration of the allocation plan creation device]
Next, with reference to FIG. 2, the structure of the allocation plan preparation apparatus which is one Embodiment of this invention is demonstrated. As shown in FIG. 2, the allocation plan creation device 10 of the present embodiment is configured by an information processing device such as a workstation, and includes a steelmaking database (DB) 11, a terminal interface 12, and a calculation unit 13.

  The steelmaking DB 11 stores steel production plan data planned in the steelmaking factory 20. The steel output plan data includes the number of steel output charges per predetermined time such as one day, data on each steel output charge (data output charge data), the number of molten steel pans, and data on each steel ladle (molten steel pan data).

  Charged steel charge data includes the time at which molten steel is discharged from the converter (starting time of molten steel), the time at which casting of the molten steel is completed (casting end time), and secondary refining for the molten steel discharged from the converter It includes at least data relating to the processing step (passing step) performed in the facility and the alloy component (steel type component) of the molten steel produced from the converter. Specifically, as shown in FIG. In correspondence with, information on steel start time, casting end time, steel type code, passage process code, titanium component (ppm), chromium component (ppm), and other components is included. Here, the steel type code means information for identifying a combination of steel type components. The passing process code means information for identifying the passing process. A titanium component, a chromium component, and other components mean content of each steel type component.

  As shown in FIG. 4, the molten steel ladle data includes at least information on the usage history of the number of times of porous use, the number of times of use of the plate, the number of times of nozzle use, and the next available time, and the molten steel pan No. Is associated with The next allocable time means a time when the corresponding molten steel ladle 3 can be allocated to the next steel charging. In this embodiment, at the end of casting of the steel charge that is currently being received or most recently received, the transport time from the casting machine to the pan center where the molten steel pan 3 is maintained, the maintenance time at the pan center, and the molten steel It is set as the time which added the conveyance time to the bottom of the converter of the pan 3.

  In addition, the conveyance time of the molten steel pan 3 is given by the constant. The maintenance time is given based on the replacement time data described later. The porous 8, the plate 6, and the nozzle 7 are prepared when the number of times of use reaches a predetermined number. The predetermined number of uses of the porous 8, the plate 6, and the nozzle 7 varies depending on the steel type of the steel output charge and the passing process. The number of uses of each part of the porous 8, plate 6, and nozzle 7 is updated each time it is used, and reset to zero when it is serviced.

  The steelmaking DB 11 also stores replacement time data indicating replacement time required for replacement of the parts of the molten steel pan 3. As shown in FIG. 5, for example, the replacement time data includes a combination of parts to be replaced (porous 8, plate 6, and nozzle 7) and a total replacement time (minutes) required for the replacement. In FIG. 5, each component is indicated by “◯” when it is replaced, and by “−” when it is not necessary to replace it.

  Data such as a steelmaking start time and a casting end time stored in the steelmaking DB 11 are rewritten via the terminal interface 12 when the operator operates the terminal device 21 connected to the allocation plan creation device 10, for example. be able to.

  The calculation unit 13 is configured by a calculation processing device such as a CPU. The calculation unit 13 loads the allocation plan creation program stored in the ROM (not shown) into the RAM, and executes the allocation plan creation program loaded in the RAM, so that the molten steel pan 3 necessary for the molten steel processing is obtained. Execute processing to allocate to the steel output charge. The calculation unit 13 can output the calculation result to the display device or output device of the terminal device 21 operated by the operator via the terminal interface 12.

  The allocation plan creation apparatus 10 having such a configuration creates an allocation plan for determining the molten steel ladle 3 to be efficiently allocated to the molten steel process by executing the following allocation plan creation process. Hereinafter, with reference to the flowchart shown in FIG. 6, the operation of the allocation plan creation apparatus 10 when executing the allocation plan creation processing will be described.

[Allocation plan creation process]
The flowchart shown in FIG. 6 starts at the timing when the operator operates the terminal device 21 to instruct the operation unit 13 to execute the allocation plan creation process via the terminal interface 12, and the allocation plan creation process is performed in step S1. Proceed to The operator instructs execution of the allocation plan creation process according to the present embodiment, for example, at the start of work.

  In the process of step S <b> 1, the calculation unit 13 reads a predetermined number of steel output charge data and molten steel ladle data to be processed from the steel output plan data stored in the steelmaking DB 11. Thereby, the process of step S1 is completed and the allocation plan creation process shifts to the process of step S2.

  In the process of step S2, the calculation unit 13 prepares predetermined N empty fixed allocation arrays. Thereby, the process of step S2 is completed, and the allocation plan creation process shifts to the process of step S3.

  Here, as shown in FIG. 7, the fixed allocation arrangement is configured by an arrangement of frames corresponding to the number of outgoing steel charges in which the outgoing steel charges that are the targets of the allocation plan are associated in the order of the outgoing steel start time. Is associated with the number of the ladle assigned to the steel charge of the frame. Each fixed allocation array is a candidate for an allocation plan. Moreover, the empty fixed allocation arrangement means that the steelmaking charge associated with each frame and the molten steel ladle number assigned to each steeling charge are unconfirmed. In the example shown in FIG. 7, this means that the number of ladle to be allocated is determined for each of the steel charges charged from the first (c = 1) to the c-th.

  In the process of step S3, the calculating part 13 sorts the steelmaking charge data acquired by the process of step S1 in order of the steelmaking start time, and associates it with the steelmaking charge frame of the fixed allocation arrangement in the order of the steelmaking start time. Thereby, the process of step S3 is completed, and the allocation plan creation process shifts to the process of step S4.

  Next, the calculation unit 13 calculates the c-th (c is an integer from 1 to the number of steel-out charges) in the i-th (i is an integer from 1 to N) fixed allocation array, The process (step S9-step S11) which confirms whether the nth (n is an integer from 1 to the number of molten steel pans in operation) can be allocated is performed.

  Specifically, the calculation unit 13 first sets 1 to the steel output charge number c (step S4). Then, the calculation unit 13 selects the i-th fixed allocation array as a confirmation target while performing a process of incrementing the fixed allocation array number i by 1 from 1 (step S5) for the c-th outgoing steel charge (step S15). (Step S6). As will be described later, the calculation unit 13 performs the process of incrementing the steel output charge number c by 1 from 1 (step S4) (step S21), and the i-th fixed allocation array for the c-th steel output charge. Repeat the process of selecting.

  Next, the calculating part 13 sorts molten steel ladle data in order of the next allocation possible time (step S7), and sets 1 to molten ladle number n (step S8). And the calculating part 13 selects the nth molten steel ladle as a confirmation object, performing the process which raises n by 1 so that it may mention later (step S9), and this molten ladle is the i-th fixed allocation. It is confirmed whether or not it can be allocated to the c-th steel charging in the array (step S10). Here, the calculating part 13 confirms whether the constraint conditions mentioned later are satisfied.

  When the n-th molten steel pan can be allocated to the c-th steel charging of the i-th fixed allocation array (step S10, Yes), the calculation unit 13 generates a temporary allocation array that does not set an upper limit on the number. The information of the selected i-th fixed allocation array is copied, and the ladle number n is stored in the c-th outgoing steel charge frame. At the same time, the calculation unit 13 updates information on the use history such as the next available time of the molten steel pan data, the number of times of porous use, the number of times of nozzle use, the number of times of plate use, etc. for the nth molten steel pan (step S11). Next, the calculation unit 13 increments n by 1 and repeats the confirmation process of steps S9 to S11 (step S12, No → Step S13 → Step S9).

  The calculation part 13 will perform the confirmation process of step S9-S11 about all the molten steel pans in operation (step S12, Yes), will select the i + 1th fixed allocation arrangement | sequence as a confirmation object, and will perform the confirmation process of step S7-S13. Repeat (Step S14, Yes → Step S15 → Step S6).

  When all of the fixed allocation arrays have been selected as confirmation targets and no information is stored in the (i + 1) th fixed allocation array (step S14, No), the arithmetic unit 13 generates the temporary allocation generated by the above processing. A process of selecting the array to a predetermined number N or less is performed. Specifically, when the generated temporary allocation array exceeds the predetermined number N (Step S16, Yes), the calculation unit 13 has a small number of molten steel pans that become cold pans for a certain period of time. In order, a selection process that adopts N temporary allocation arrays is performed (step S17). When the generated temporary allocation array is equal to or less than the predetermined number N (No at Step S16), the arithmetic unit 13 advances the process to Step S18.

  Then, the calculation unit 13 performs a process of rewriting the N or less temporary allocation arrays adopted to the same number of fixed allocation arrays (step S18). Specifically, the calculation unit 13 resets the information stored in the N fixed allocation arrays to be empty, and then copies the information of the N or less temporary allocation arrays adopted. . Thereafter, the calculation unit 13 deletes the temporary allocation array of the copy source (step S19). Thereby, N or less definite allocation arrangement | sequences by which the molten steel pan which can be allocated with respect to the steel-out charge until cth are matched are produced.

  The calculation unit 13 increments the steel output charge number c by 1 and repeats the above steps S5 to S19 (Step S20, No → Step S21 → Step S5). When molten steel pans that can be allocated for all steel charges are associated (Yes in step S20), N or less fixed allocation arrays that are associated with all steel charges are allocated plans. Created as a candidate. In that case, the calculation unit 13 selects an optimum fixed allocation array as the allocation plan from the prepared fixed allocation arrays of the predetermined number N or less (that is, selects the allocation sequence having the highest evaluation as the allocation plan) or evaluates A plurality of allocation arrangements having a high value are selected (step S22). As the optimum fixed allocation array, for example, as in the process of step S17, a fixed allocation array with a small number of molten steel pans that have been in the cold pan state for a certain period of time is selected. Thereby, the process of step S22 is completed and a series of allocation plan preparation processes are complete | finished.

  Moreover, when selecting the allocation array in steps S17 and S22, the allocation array may be evaluated by the number of molten steel pans used during the planning period, instead of the number of molten steel pans that have become cold pots. In this case, the smaller the number of molten steel pans used in the planning period, the higher the evaluation. In addition, the following index may be added.

(1) Number of times the molten steel pans to be used preferentially specified by the operator are allocated in the allocation array (2) Number of times to allocate the molten steel pans that have been serviced before the previously completed molten steel pans

  When the index (1) is added, the evaluation is increased as the number of times is increased, and when the index (2) is added, the evaluation is increased as the number of times is decreased. In addition, when adding at least one index as described above, the weighted linear sum may be used as a new evaluation, and the priority of the index is set, and the allocation array is sorted in descending order of the priority. The evaluation may be made higher from the higher allocation arrangement.

  In step S17, the discarded allocation array is stored in the memory area. If there is no temporary allocation array generated in step S16, N items are selected from the most recently stored allocation arrays. Proceed to S18. At this time, when the molten steel pans for the c-th outgoing steel charge are determined for each allocation arrangement selected, the allocation pan selection is started from the c + 1-th outgoing steel charge.

  Here, with reference to FIG. 8, the specific procedure of the above-described allocation plan creation processing will be described. In FIG. 8, among the N fixed allocation arrays (candidate for allocation plan) in which the molten steel pans to be allocated to the c-1 steel output charges are determined, the c-th steel output charge is determined for the i-th fixed allocation array. The number of molten steel pans that can be allocated was n = 7, 10, 12. Therefore, three temporary allocation arrays are generated from the i-th fixed allocation array. Similarly, for the (i + 1) th fixed allocation array, a plurality of temporary allocation arrays are generated in which molten steel pans that can be allocated to the c-th outgoing steel charge are associated with each other. In this way, when N or more temporary allocation arrays are generated in which the molten steel pans that can be allocated to the c-th steel charge are generated from the N fixed allocation arrays, N of them are adopted. To a new N fixed allocation array.

  FIG. 9 is a diagram exemplifying the fixed allocation array (allocation plan) selected in the process of step S22. The allocation plan shows a schedule of a plurality of steelmaking charges to be processed (steeling start time, casting end time, maintenance completion time) and molten steel ladle 3 assigned to each steeling charge. In the plan illustrated in FIG. 9, for each outgoing steel charge, whether to replace each part of the porous 8, the plate 6, and the nozzle 7, the maintenance time including the part replacement time, and the molten steel pan 3 are empty pans. Including empty pot time.

[Restrictions]
Next, a specific example of the constraint condition considered in the process of step S10 described above will be described. In addition, this constraint condition is not limited to the constraint conditions 1-4 illustrated below.

[Constraint 1]
First, as an example of the constraint condition, the molten steel pan 3 cannot receive the next steel output charge until the time when it can be allocated after maintenance is completed after the casting process of the steel output charge received. Is mentioned. Here, as described above, the allocation available time is the transfer time from the casting machine to the ladle center where the molten steel pan is maintained, and the pan at the end of the casting of the steel charge that is currently being received or most recently received. It is the time when the maintenance time at the center and the conveyance time to the bottom of the furnace of the molten steel pan are added. For example, as shown in FIG. 10A, the steel discharge charge C2 is started after the end of casting of the steel discharge charge C1 assigned to the molten steel pan N1, but before the maintenance of the molten steel pan N1 is completed. Since the steel is started, it cannot be attracted to the molten steel pan N1. Therefore, as shown in FIG. 10B, the steelmaking charge C2 is assigned to a molten steel pan N2 different from the steelmaking charge C1, so that this constraint condition is satisfied.

[Restriction condition 2]
Moreover, the constraint condition that the molten steel pan 3 (cold pan) which became the empty pan and was cooled cannot be allocated depending on the outgoing steel charge is illustrated. For example, FIG. 11A and FIG. 11B exemplify a case where there is a constraint that the steel output charge C3 cannot be attracted to a molten steel pan that has become a cold pan after time T has elapsed since it became an empty pan. Yes. Here, whether or not it is a cold pot is determined using the time T as a threshold value. Moreover, the specific steel-out charge which has such a constraint condition is determined by a passage process and a steel grade component. As illustrated in FIG. 11A, since the start of the steel start of this specific steel output charge C3 takes time T or more from the end of casting of the previous steel output charge C1 in the molten steel pan N1, the steel output charge C3 is changed to the molten steel. Cannot be applied to pan N1. Therefore, as illustrated in FIG. 11B, by assigning the steel output charge C3 to the molten steel pan N2 whose time from the end of casting of the previous steel output charge C2 to the start of steel output of the steel output charge C3 is less than time T. This constraint is satisfied.

[Restriction condition 3]
Moreover, the restriction | limiting condition that the steel type component of the outgoing steel charge which can be subsequently applied to this molten steel pan 3 is limited by the steel type component of the outgoing steel charge previously allocated to the molten steel pan 3 is illustrated. For example, FIG. 12A and FIG. 12B show the constraint that the titanium component of the previous steel charge C1 must be X ₁ % or more and the titanium component of the next steel charge to be allocated must be X ₂ % or more. A case is illustrated. For this reason, as shown in FIG. 12A, the molten steel pan N1 cannot receive a steel output charge C2 whose titanium component is less than X ₂ % after the steel output charge C1 whose titanium component is X ₁ % or more. On the other hand, as shown in FIG. 12B, the steel output charge C3 whose titanium component is X ₂ % or more can be attracted to the molten steel pan N1 following the steel output charge C1 whose titanium component is X ₁ % or more. Therefore, in FIG. 12B, among the steel output charges C2 and C3 subsequent to the steel output charge C1, the steel output charge C3 with the latest steel output start time is assigned to the molten steel pan N1, and the steel output charge C2 that starts the steel output first. This constraint is satisfied by assigning to another molten steel pan N2.

[Restriction condition 4]
Moreover, the restriction | limiting condition that the maintenance time of the molten steel pan 3 changes with parts to be replaced | exchanged is illustrated. For example, the number of times of use of each part of the porous 8, the plate 6, and the nozzle 7 increases every time the steel is charged. When the number of times of use exceeds a predetermined number, each part is replaced. The time required for parts replacement varies from part to part. Therefore, the maintenance time including the replacement time of parts varies depending on the parts to be replaced. The part replacement time is set by the calculation unit 13 with reference to replacement time data (see FIG. 5) of the steel making DB 11.

  In the present embodiment, an allocation plan that satisfies the constraints 1 to 4 is extracted in the process of step S10. In addition, in the process of step S10, when the interval between the steel start time of the selected c-th steel charge and the next available time of the n-th molten steel pan is equal to or greater than the predetermined time X, the restriction that the provision is impossible Conditions may be added. As a result, it is possible to prevent the preparation of an allocation plan that takes a long time from when the molten steel pan becomes an empty pan until it is allocated to the next steel charging. In addition, when there is a shortage of available molten steel pots, it is possible to secure the available molten steel pots by adjusting the length of the predetermined time X to loosen the constraint conditions.

  As is clear from the above description, in the allocation plan creation process by the allocation plan creation device 10 according to an embodiment of the present invention, the calculation unit 13 can determine whether the number of temporary allocation arrays exceeds a predetermined number N. The optimal solution is searched for while adopting N of them in the fixed allocation array as allocation plan candidates. The predetermined number N is determined to be as large as possible within a range that does not exceed the memory among a plurality of appropriate values. Further, when the calculation time becomes longer at the determined N, the value is adjusted to be appropriately small. For this reason, it is possible to prevent the allocation plan creation apparatus from exceeding the memory and increasing the calculation time of the optimal solution search due to the explosion of the number of temporary allocation arrays and the number of fixed allocation arrays. Thereby, the molten steel ladle can be efficiently allocated to the molten steel processing according to the steel output plan without requiring adjustment of parameters that determine the level of the optimum solution.

[Example]
FIG. 13 is a diagram illustrating an allocation plan created by an operator as in the past. Moreover, FIG. 14 is a figure which illustrates the allocation plan created by the allocation plan creation process of the molten steel pan of this invention. In addition, the number described in the outgoing steel charge shown by the band in each figure shows the identification information of the outgoing steel charge. As shown in FIGS. 13 and 14, the ladle No. used in the plan of FIG. 19 is not used in the allocation plan of FIG. FIG. 15 is a diagram illustrating the empty pan time distribution of the allocation plan shown in FIG. 13 and the empty pan time distribution of the allocation plan shown in FIG. In FIG. 15, in the empty pan time distribution of the allocation plan shown in FIG. 13, the average empty pan time was 2 hours and 37 minutes, whereas in the empty pan time distribution of the allocation plan shown in FIG. Was 2 hours and 15 minutes, shortened by 22 minutes. The value of N was 3000 and the calculation time was 5 seconds. Thereby, it was shown by this invention that empty pot time can be shortened and few molten steel pans can be operated efficiently.

  Although the embodiment to which the invention made by the present inventor is applied has been described above, the present invention is not limited by the description and the drawings that form a part of the disclosure of the present invention according to this embodiment. That is, other embodiments, examples, operational techniques, and the like made by those skilled in the art based on this embodiment are all included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Converter 2 Molten steel 3 Molten steel pan 4 Introducing pipe 5 Continuous casting equipment 6 Plate 7 Nozzle 8 Porous 10 Reserve plan preparation apparatus 11 Steelmaking database 12 Terminal interface 13 Calculation part 21 Terminal apparatus

Claims (5)

An allocation plan creation method for a molten steel pan, which creates an allocation array as an allocation plan that associates the ladle numbers of the molten steel pans to be allocated to each of the outgoing steel charges arranged in order of the outgoing steel start time,
A steel charging charge selection step for selecting the steel charging start number that has the earliest time of steelmaking among the steel charging charges that have not yet been associated with the molten steel ladle number;
Allocation array selection for selecting one of a predetermined number or less of allocation arrays to which the ladle numbers of the ladle to be allocated to all or a part of the steel charging charges arranged in order of the steelmaking start time are not yet associated Steps,
The allocation sequence selected in the allocation sequence selection step is added to the allocation sequence to correspond to each of the ladle numbers of one or more molten steel pans that can be allocated to the outgoing steel charge selected in the outgoing steel charge selection step. An information update step of updating the information regarding the use history of each molten ladle of each replaced arrangement array,
When all of the allocation arrangements are selected in the allocation arrangement selection step and the processing of the information update step for each of the allocation arrangements selected is completed, a predetermined evaluation is performed on each of the allocation arrangements that have been replaced. An adopting step of adopting the predetermined number or less of the allocation arrangement;
All of the outgoing steel charges are selected in the outgoing steel charge selection step, and when the processing of the allocation arrangement selecting step, the information updating step and the adopting step for each selected outgoing steel charge is completed, the predetermined used A predetermined evaluation for each of the number of allocation arrays below the number, and select the allocation array with the highest evaluation as an allocation plan, or an allocation plan creation step of selecting a plurality of allocation arrays with the highest evaluation;
A method for preparing an allocation plan for a molten steel pan, comprising:   In the information updating step, a predetermined constraint condition is satisfied based on the start time of the steel output and the time that can be allocated to the next steel charge included in the use history information of each molten steel pan. The molten steel ladle allocation method according to claim 1, further comprising: determining a molten steel ladle that can be allocated to the outgoing steel charge.   3. The method for creating an allocation plan for molten steel pans according to claim 1 or 2, wherein, in the adoption step and / or the allocation plan creation step, the evaluation is made higher as the number of molten steel pans used in the planning period is smaller.   In the recruitment step and / or the allocation plan creation step, after the casting of each steel charge is completed and emptied, the ladle time of the molten steel pan until the next steel charge is allocated becomes a predetermined threshold value or more. The method for preparing an allocation plan for molten steel pans according to claim 1 or 2, wherein the evaluation is made higher as the number of molten steel pans is smaller. An allocation plan creation device for a molten steel ladle that creates an allocation array as an allocation plan that associates the ladle numbers of the ladle to be allocated to each of the outgoing steel charges arranged in order of the outgoing steel start time,
Outgoing charge selection means for selecting the one with the earliest start time out of the outgoing steel charges not yet associated with the ladle number;
Allocation array selection for selecting one of a predetermined number or less of allocation arrays to which the ladle numbers of the ladle to be allocated to all or a part of the steel charging charges arranged in order of the steelmaking start time are not yet associated Means,
The allocation array selected by the allocation array selection means is added to the allocation array to correspond to each of the ladle numbers of one or more molten steel pans that can be allocated to the outgoing steel charge selected by the outgoing steel charge selection means. Information updating means for updating the information regarding the use history of each molten ladle of each replaced arrangement array,
When all of the allocation arrangements are selected by the allocation arrangement selection unit and the processing by the information updating unit for each of the allocation arrangements selected is completed, a predetermined evaluation is performed on each of the allocation arrangements that have been replaced. Adopting means adopting the predetermined number or less of the allocation arrangement;
All of the outgoing steel charges are selected by the outgoing steel charge selecting means, and the predetermined arrangement adopted when processing by the allocation arrangement selecting means, the information updating means, and the adopting means for each selected outgoing steel charge is completed. A predetermined evaluation for each of the number of allocation arrays below the number, and select the allocation array with the highest evaluation as the allocation plan, or an allocation plan creating means for selecting a plurality of allocation arrays with the highest evaluation;
An apparatus for preparing an allocation plan for a molten steel pan, comprising:

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