Rolling plan creation apparatus and rolling plan creation method

Abstract

To provide a rolling plan generation device and a rolling plan generation method capable of generating a rolling plan of hot rolling for guaranteeing the establishment of an operation.SOLUTION: A rolling plan generation device (10) is used for a synchronous operation of a steel making process performed by a continuous casting machine and a rolling process for hot-rolling, by a hot rolling machine, a slab cast by the continuous casting machine, and generates a rolling plan of hot rolling. This device comprises: an acquisition unit (11) that acquires input information including inventory information, casting information, heating information, rolling information, and facility information; and a calculation unit (12) that executes calculation for generating a rolling plan. The calculation unit generates the rolling plan by determining the interfering position of a directly fed material so as to satisfy physical distribution constraints for an initial rolling plan included in the rolling information, and determines whether to execute interference or temporary placing at a DHCR yard for a slab which has arrived at a turner.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a rolling schedule creation device and a rolling schedule creation method. In particular, the present disclosure relates to a rolling schedule creation device and a rolling schedule creation method for determining the rolling order of hot rolling in consideration of logistics.

Background Art

[0002] Many slabs (cast slabs) cast in the steelmaking process are stored in a yard (hereinafter, slab yard) where the slabs are stored while dissipating heat until they are rolled. The slabs are reheated in a heating furnace to a temperature at which they can be rolled after being incorporated into the rolling plan, and then rolled. Here, some slabs are directly sent to a dedicated heating furnace at a high temperature as direct feed materials without passing through the slab yard and are rolled. Rolling that charges the heating furnace at a high temperature is called DHCR (Direct Hot Charge Rolling). Also, an operation in which yard materials (non-direct feed materials), which are slabs passing through the slab yard, and direct feed materials are mixed is called a matching operation. The matching operation is useful not only for improving production efficiency but also from the viewpoint of energy saving by suppressing heat dissipation.

[0003] However, in order to execute the matching operation without omission, it is necessary to satisfy various constraints. For example, there are many constraints regarding the steel type, thickness, temperature, etc. of the slabs in the rolling order, and a technique for determining a rolling schedule so as to achieve a high rolling efficiency while satisfying these constraints is required. Also, in order to execute rolling without delay, a technique for controlling the logistics from casting to rolling is required. Furthermore, depending on the rolling situation and the logistics situation at the planning execution stage, a situation may occur where even a slab that can be subjected to DHCR has to be used as a non-direct feed material. A technique for appropriately selecting from slabs that can be subjected to DHCR and incorporating them into the matching schedule is necessary.

[0004] Patent Document 1 describes a method that enables DHCR in an order different from the casting order by performing rearrangement on a charging table for slabs placed on the charging table of the heating furnace in accordance with the casting order so that the difference in the finish rolling thickness of each slab becomes as small as possible.

[0005] The technology described in Patent Document 2 represents inventory slabs and direct slabs using a two-dimensional grid graph, and determines the shortest path by representing the distance between grids with attributes between slabs or waiting times. By determining the shortest path in this way, a rolling plan that takes into account overlapping operations can be created.

[0006] Patent Document 3 discloses a system for determining the rolling order during interlocking operations for high-temperature charging slabs and slabs that are temporarily placed in a storage area (slab cooling yard) to cool, and then, after adjusting the heating furnace charging order, are charged into a heating furnace for normal temperature charging. High-temperature charging slabs include slabs extracted from a continuous casting machine and directly charged into a heating furnace for high-temperature charging, and slabs extracted from a continuous casting machine, temporarily placed in a heat retention pit dedicated to high-temperature cast slabs, and then charged into a heating furnace for high-temperature charging. Patent Document 3 describes a method for deciding whether to charge a slab directly into the heating furnace or a slab temporarily placed in a heat retention pit, based on the number of interlocking slabs.

[0007] Patent Document 4 describes a method for predicting the timing of hot rolling arrival and rolling operation status for slabs from a steelmaking plant to a hot rolling mill using logistics simulations, and then optimizing the lot configuration based on the results. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2007-246994 [Patent Document 2] Patent No. 5466699 [Patent Document 3] Patent No. 6229632 [Patent Document 4] Patent No. 4987795 [Overview of the project] [Problems that the invention aims to solve]

[0009] However, the technology in Patent Document 1 only allows for rearranging the casting order on the charging table and is not suitable for operations that include temporary storage using a DHCR yard. Furthermore, it does not correspond to rolling plans for interim operations. The technology in Patent Document 2 creates rolling plans for interim operations, but does not consider rolling plans that allow for rearranging the casting order of slabs, and does not consider the rearrangement of slabs within the DHCR yard during interim operations. The technology in Patent Document 3 considers slabs temporarily stored in a heat retention pit, but does not consider logistical constraints before and after the heat retention pit, and may propose rolling orders that are difficult to implement in actual operations. The technology in Patent Document 4 predicts the arrival timing of hot rolling using simulation, but it schedules lot formation for slabs in stock arriving at the slab yard. Therefore, it does not create plans for interim operations and does not consider logistics from arrival timing to the heating furnace.

[0010] In view of these circumstances, the purpose of this disclosure is to provide a rolling plan creation device and a rolling plan creation method that can create a hot rolling plan that ensures the operation of the rolling mill. [Means for solving the problem]

[0011] (1) A rolling plan creation apparatus according to one embodiment of the present disclosure is A rolling planning device used in the synchronous operation of a steelmaking process using a continuous casting machine and a rolling process in which slabs cast by the continuous casting machine are hot-rolled in a hot-rolling mill, for creating a rolling plan for the hot-rolling process, An acquisition unit that acquires input information including inventory information, casting information, heating information, rolling information, and equipment information, It comprises a calculation unit that performs calculations for creating a rolling plan, The aforementioned arithmetic unit, The rolling plan is created by determining the insertion positions of the direct-shipped materials so as to satisfy the logistics constraints with respect to the initial rolling plan included in the rolling information. Logistical simulations for creating the aforementioned rolling plan determine whether to perform a direct insertion of the slab upon its arrival at the turner or to temporarily store it at the DHCR yard.

[0012] (2) As one embodiment of the present disclosure, in (1), The aforementioned logistics constraints include the ability to load the directly delivered material into a heating furnace for heating, The determination of whether or not the vehicle can be charged into the heating furnace is made based on at least one of the loading status of the traverse trolley and the operating status of the crane.

[0013] (3) In one embodiment of the present disclosure, in (1) or (2), The calculation unit determines the insertion position of the direct material so that the heating constraints are satisfied, The aforementioned heating constraints include the fact that the maximum slab width that can be charged into the heating furnace, calculated based on the heating furnace length, the spacing between slabs in the furnace, the number of slabs in the furnace, and the width of each slab, is equal to or greater than the width of the candidate slab, and that the time spent in the furnace is equal to or greater than the minimum time spent in the furnace.

[0014] (4) As one embodiment of the present disclosure, in (3), The calculation unit, when there are multiple rolling sequences that can be used interchangeably for the direct-shipped material, selects the rolling sequence that results in the earliest extraction time from the heating furnace.

[0015] (5) In one embodiment of the present disclosure, in any of (1) to (4), The system includes an output unit that outputs a logistics plan that satisfies the logistics constraints along with the created rolling plan.

[0016] (6) As one embodiment of the present disclosure, in (5), The output unit outputs information about the slab that is returned to the slab yard because the fitting has not been determined.

[0017] (7) In one embodiment of the present disclosure, in any of (1) to (6), The calculation unit creates the rolling plan when the slab is extracted from the heating furnace, when the slab arrives at the turner, or when the initial rolling plan is changed.

[0018] (8) The rolling plan creation method according to an embodiment of the present disclosure is used in the synchronized operation of a steelmaking process by a continuous casting machine and a rolling process in which the slab cast by the continuous casting machine is hot-rolled by a hot rolling mill, and is a rolling plan creation method executed by a rolling plan creation device that creates a rolling plan for the hot rolling, obtaining input information including inventory information, casting information, heating information, rolling information, and equipment information; executing calculations for creating a rolling plan, and the calculations include creating the rolling plan by determining the butting position of the direct feed material so that the logistics constraints are satisfied with respect to the initial rolling plan included in the rolling information; judging whether to carry out butting for the slab that has arrived at the turner and whether to carry out temporary storage in the DHCR yard by means of a logistics simulation for creating the rolling plan.

Effect of the Invention

[0019] According to the present disclosure, it is possible to provide a rolling plan creation device and a rolling plan creation method that can create a rolling plan for hot rolling that ensures the success of the operation.

Brief Description of the Drawings

[0020] [Figure 1] FIG. 1 is a diagram illustrating a production line to which the rolling plan creation method according to an embodiment of the present disclosure is applied. [Figure 2] FIG. 2 is a schematic diagram of the DHCR yard. [Figure 3] FIG. 3 is a diagram for explaining the butting of the direct feed material. [Figure 4] [[ID=ip10]]FIG. 4 is a diagram showing a configuration example of a rolling plan creation device and a flow of processing of a rolling plan creation method according to an embodiment of the present disclosure. [Figure 5] Figure 5 shows the processing flow for determining whether a move is successful. [Figure 6] Figure 6 shows the details of the process for determining the interlocking materials and interlocking locations. [Figure 7] Figure 7 shows the process flow for determining whether logistical constraints are met. [Figure 8] Figure 8 shows the process flow for determining whether the heating constraints are met. [Figure 9] Figure 9 is a diagram illustrating the rearrangement. [Figure 10] Figure 10 shows the process for determining how to handle slabs upon arrival at Turner. [Figure 11] Figure 11 shows the process for determining the temporary pile. [Figure 12] Figure 12 shows the stacking constraint determination. [Figure 13] Figure 13 is a diagram illustrating the difference in slab width. [Figure 14] Figure 14 is an example of information regarding the charging temperature over time. [Figure 15] Figure 15 shows the equipment specifications. [Figure 16] Figure 16 is a reference table regarding stacking constraints within the DHCR yard. [Figure 17] Figure 17 shows information about the slabs within the DHCR yard. [Figure 18] Figure 18 shows information regarding the casting plan when input information is acquired. [Figure 19] Figure 19 shows information regarding the hot rolling plan when input information is acquired. [Figure 20] Figure 20 shows the constraints on the consistency of the finished thickness of the rolled material. [Figure 21] Figure 21 shows the determined joint rolling plan. [Figure 22] Figure 22 shows a slab to be sent to the DHCR yard or the high-temperature charging furnace. [Figure 23]Figure 23 shows the crane transport plan for the DHCR yard. [Figure 24] Figure 24 shows the crane transport plan for the DHCR yard. [Modes for carrying out the invention]

[0021] A rolling plan creation apparatus 10 (see Figure 4) and a rolling plan creation method according to one embodiment of the present disclosure will be described below with reference to the drawings.

[0022] Figure 1 illustrates a manufacturing line to which the rolling plan creation method according to this embodiment is applied. Slabs obtained by casting from molten steel in a continuous casting machine move along a table and arrive at a turner. On the turner, it is possible to rotate the slab to change its direction of movement. If a slab that arrives at the turner is not to be sent directly to the hot rolling mill, it rotates 90 degrees and proceeds to the hot rolling mill via the steelmaking slab yard or finishing plant. If a slab that arrives at the turner is to be sent directly, it moves straight ahead and then proceeds to the hot rolling mill line by traverse cart. Each slab is heated in a heating furnace before being rolled in the hot rolling mill. At this time, slabs that do not arrive directly at the hot rolling mill are temporarily stored in the slab yard and are charged into a heating furnace for normal temperature charging. On the other hand, slabs that are sent directly are charged into a heating furnace for high temperature charging. Here, slabs that do not arrive directly at the hot rolling mill (hot rolling mill) are also called non-direct materials. Slabs that are delivered directly to the hot rolling mill (hot rolling mill) are also called direct-delivery materials.

[0023] Figure 2 is a schematic diagram of the DHCR yard. While the direct-shipped material moves from the turner to the heating furnace, there is a temporary storage and heat retention pit (hereinafter referred to as the DHCR yard) dedicated to high-temperature slabs, where slabs to be charged into the high-temperature charging furnace can be temporarily stored while maintaining their temperature. When temporarily stored, the slabs are transported by crane on a traverse trolley, placed into the DHCR yard through an open section of the lid, and stacked on one of the piles. At the appropriate time thereafter, the slabs are unloaded from the DHCR yard onto the traverse trolley by crane and charged into the heating furnace. This allows for the temporary storage of slabs at a high temperature even when the high-temperature charging furnace is full, suppressing heat loss in the slab yard, and also makes it possible to charge the high-temperature charging furnace in an order different from the order of arrival from the continuous casting machine. After being charged into the heating furnace, the slabs are heated to an appropriate temperature and then extracted from the heating furnace. At this time, slabs are extracted in a first-in, first-out order in each heating furnace, and each slab is merged into a single line before being hot-rolled. The hot rolling sequence must take various constraints into consideration, and the slabs must be charged into the furnace in an order that satisfies these constraints. When planning the rolling sequence, for example, the period from immediately after the final roll change in hot rolling to the next roll change is considered as one unit (cycle), and the slab configuration is created within each cycle. As shown in Figure 3, the slab configuration of non-direct materials that are normally charged into the furnace for high-temperature charging (hereinafter referred to as the base cycle) is created once, and the rolling plan is constructed by inserting direct materials into the base cycle in a way that satisfies the constraints of hot rolling and the furnace. However, slabs of direct materials that are not included in the rolling plan and remain for a long time, making high-temperature charging impossible, are returned to the slab yard at an appropriate time.

[0024] Figure 4 is a diagram showing an example configuration of the rolling plan creation device 10 according to this embodiment, and the arrows indicate the processing flow of the rolling plan creation method executed by the rolling plan creation device 10. As described above, the rolling plan creation device 10 is used in synchronous operation of a steelmaking process using a continuous casting machine and a rolling process in which slabs cast by the continuous casting machine are hot-rolled in a hot-rolling mill, and creates a rolling plan for hot rolling. The rolling plan creation device 10 comprises an acquisition unit 11, a calculation unit 12, and an output unit 13. The rolling plan creation device 10 may be a computer as its hardware configuration. The rolling plan creation device 10 may also have the following software configuration. One or more programs used to control the operation of the rolling plan creation device 10 are stored in a storage device accessible from the rolling plan creation device 10. When the program stored in the memory device is read by the processor (e.g., CPU) of the rolling plan creation device 10, the processor is made to function as an acquisition unit 11, a calculation unit 12, and an output unit 13.

[0025] The rolling plan creation device 10 is configured to communicate with a higher-level system 20. The higher-level system 20 is a system that manages and controls a manufacturing line, including, for example, continuous casting and hot rolling, and may consist of a different computer from the rolling plan creation device 10. The rolling plan creation device 10 acquires various data from the higher-level system 20, including the input information described later, which is necessary for the calculation (simulation) of the rolling plan creation. The rolling plan creation device 10 also outputs the calculation results, including the created rolling plan, to the higher-level system 20.

[0026] The acquisition unit 11 acquires input information. The input information includes inventory information, casting information, heating information, rolling information, and equipment information. Inventory information includes information such as slabs in the DHCR yard and slabs in transit. Casting information includes information such as the dimensions and steel type of the cast slabs. Heating information includes information such as the slabs in the heating furnace and the heating status. Rolling information includes the initial rolling plan and rolling constraints. The initial rolling plan corresponds to the parent cycle described above. The initial rolling plan may be created, for example, by a known planning method by the higher-level system 20. Equipment information includes the presence or absence of failures of each piece of equipment, equipment capacity specifications, and space constraints.

[0027] The calculation unit 12 performs calculations to create a rolling plan. In this embodiment, the calculations are mainly simulations, and the calculation unit 12 may be described as a simulator (logistics simulator). However, the calculations performed by the calculation unit 12 are not limited to simulations, and it may perform various calculations, judgments, and decisions related to the creation of the rolling plan. The input information acquired by the acquisition unit 11 is passed to the simulator. The simulator performs a collision determination calculation at a predetermined collision determination timing (rolling plan update timing) based on the logistics simulation. In this embodiment, the simulator determines whether to perform a collision on the slab that has arrived at the turner or to perform temporary storage at the DHCR yard.

[0028] The output unit 13 outputs the results of calculations performed by the calculation unit 12. The results include the rolling plan and logistics plan created by the calculation unit 12. The rolling plan created by the calculation unit 12 is an updated rolling plan in which direct material is substituted for the initial rolling plan (corresponding to the base cycle). In this embodiment, the output unit 13 outputs the rolling plan along with a logistics plan that satisfies the logistics constraints described later. The higher-level system 20 receives the updated rolling plan and performs hot rolling control according to the updated rolling plan, thereby improving manufacturing efficiency and saving energy by suppressing heat dissipation. Here, as will be explained in a later embodiment, there may be slabs that are temporarily placed in the DHCR yard and returned to the slab yard without a slab substituted (slabs that cannot be substituted). The output unit 13 may include information on slabs that cannot be substituted in the output results.

[0029] Figure 5 shows the processing flow for collision detection. The collision detection process is performed using a logistics simulator. First, information about the base cycle to be collided is obtained from the initial rolling plan included in the rolling information. For the base cycle, collision detection is performed on slabs that have already been charged into the high-temperature charging furnace. Next, collision detection is performed on slabs that can be charged into the high-temperature charging furnace. In other words, calculations and determinations regarding collision positions, etc., are performed preferentially for slabs that have already been charged into the high-temperature charging furnace. Then, the collision material is included in the initial rolling plan, and the overall rolling plan is updated. Here, collision material refers to the slabs used for collision. In this example, collidable slabs (slabs that are candidates for collision material) include slabs temporarily stored in the DHCR yard, slabs that have arrived at the turner, and slabs included in the logistics route from the turner to the traverse trolley. Furthermore, the timing for updating the rolling plan (i.e., the timing for creating the rolling plan in the calculation unit 12) can be, for example, when the slab is extracted from the high-temperature charging furnace, when the slab arrives at the turner, when the rolling cycle of the base material is changed, or at any other time at the user's discretion.

[0030] Figure 6 shows the details of the process for determining the interlocking material and interlocking position. As shown in Figure 6, for all candidate slabs, it is determined whether the logistics constraints, rolling constraints, and heating time are met, and the interlocking material and interlocking position are determined. Figure 7 shows the flow of the process for determining whether the logistics constraints are met by logistics simulation. All direct-shipped materials require a traverse trolley to reach the heating furnace. Since it is impossible to load a new slab while other slabs are loaded on the traverse trolley, the loading status of the traverse trolley is checked. However, for slabs that have already been heated in the furnace, the possibility of loading them onto the trolley is not considered. Next, it is determined whether the crane in the DHCR yard is operational. The crane is installed at the top of the DHCR yard, as shown in the schematic diagram of the DHCR yard in Figure 2, and can deliver slabs from the DHCR yard to the traverse trolley. However, for slabs that are heated in the furnace without passing through the DHCR yard, the possibility of crane operation is not considered. In this way, at least one of the loading status of the traverse trolley and the operating status of the cranes in the DHCR yard is predicted based on the results of the logistics simulation, and a decision is made as to whether or not the direct shipment materials can be loaded into the heating furnace.

[0031] Next, constraints on hot rolling are determined. These constraints are numerous. For example, materials with strict quality requirements must be processed before the surface condition of the rolling rolls deteriorates. Also, the rolling rolls wear down in a stepped manner depending on the width of the slab being processed. To prevent this stepped wear of the rolling rolls from affecting quality, a constraint is needed to process narrower slabs after wider slabs. There may also be limitations on the types of steel that can be used for the preceding and succeeding slabs, as well as operational constraints on slabs with small finishing thicknesses (thin materials). These constraints are loaded into the simulator, and it is determined whether the constraints are satisfied for the joint position.

[0032] Finally, heating constraints are determined. Figure 8 shows the flow of the process for determining whether the heating constraints are met. Let L be the length of the heating furnace and d be the spacing between slabs inside the furnace. The maximum slab width (W) that can be charged into the heating furnace is calculated in the logistics simulator using the following equation (1).

[0033]

number

[0034] Here, N is the number of slabs in the furnace, and ω is the width of each slab. If the maximum slab width that can be loaded into the heating furnace is greater than or equal to the width of the candidate slabs, it is guaranteed that all slabs in the heating furnace will be installed at the predetermined intervals. The heating constraints include the fact that the maximum slab width (W) that can be loaded into the heating furnace is greater than or equal to the width of the candidate slabs and that the requirements for furnace dwell time, described below, are met.

[0035] The extraction time of the interlocking material from the heating furnace is set so that the interlocking material is placed between the slabs before and after the interlocking position. Here, the extraction time of the leading slab in the furnace in Figure 8 is the extraction time of the leading slab located at the very end of the heating furnace for high-temperature charging. Since slabs are extracted in a first-in, first-out manner in the heating furnace, it is necessary that the extraction time be later than all leading slabs (satisfying the "≧" in the inequality expression in Figure 8, which is greater than or equal to). Finally, the time spent in the furnace is determined. The minimum time spent in the furnace is calculated from the target extraction temperature of the slab and the temperature at the time of charging, and is determined based on the minimum required heating time. The minimum time spent in the furnace varies depending on the heating pattern, but is set to, for example, 60 minutes. The time spent in the furnace of a slab can be calculated from the difference between the extraction time from the heating furnace and the charging time into the heating furnace.

[0036] When there are multiple possible rolling sequences (candidate insertion positions) for a given slab, the rolling sequence that results in the earliest extraction time from the high-temperature charging furnace is selected. This selection minimizes the heating constraint imposed by the extraction time of the preceding slab in the furnace. Furthermore, when there are multiple possible slabs with the same extraction time, the priority order may be slabs being transported by the traverse cart, slabs arriving at the turner, and slabs in the DHCR yard. Among the slabs in the DHCR yard, priority may be given to slabs stacked on the pile on the traverse cart side and stacked higher on the pile to reduce crane operating time. Slabs being transported by the traverse cart and slabs arriving at the turner are at a higher temperature than slabs in the DHCR yard, and are therefore given priority as they reduce the operating time of the crane and traverse cart. In this manner, the slab to be charged into the high-temperature charging furnace is determined, and the insertion rolling sequence is updated.

[0037] Figure 10 shows the process for determining how to handle slabs that have arrived at Turner (e.g., fitting determination). In the "DHCR possible" determination based on logistics simulation, slabs requiring finishing processes are excluded based on casting information. In the "fit determination" based on logistics simulation, slabs that do not meet the constraints and are determined not to be fitted are then determined to be able to be temporarily stored in the DHCR yard. Slabs that cannot be temporarily stored in the DHCR yard are temporarily stored in the slab yard.

[0038] Figure 11 shows the process for determining the temporary storage pile. After determining the logistics constraints according to Figure 7, when the slabs are transported from the traverse trolley and temporarily stored in the DHCR yard, the pile to which they will be temporarily stored is determined taking into account various stacking constraints. The temporarily stored slabs are then dispensed onto the traverse trolley again by a crane at the appropriate time. If the dispensed slab is not at the top of the pile, it is necessary to rearrange it as shown in Figure 9. When rearranging, the destination pile is determined in the same way as when the slabs are temporarily stored in the DHCR yard, taking into account various stacking constraints, following the flow shown in Figure 11. Here, in the case of rearranging, the traverse trolley is not used, so the acceptance or rejection of the traverse trolley is not considered. Figure 12 shows the stacking constraint determination. When storing products and semi-finished products in stacks, there are generally constraints on the height and width difference of the piles due to the risk of collapse, etc. The width difference of the slabs is calculated as "ω1-ω2" using the width of the uppermost slab (ω1) and the smallest slab width among the lower slabs (ω2), as shown in Figure 13. The constraint is that this width difference must be less than or equal to the given maximum allowable width difference.

[0039] Based on the above constraints, if there are multiple candidates for temporary storage and relocation sites, the site with the shortest crane operating time will be selected. Here, crane operating time, in the case of receiving at the DHCR yard, is the time from when the crane starts moving until the slab is placed on the temporary storage site and the crane is hoisted up. In the case of relocation, crane operating time is the time from when the crane starts moving until the relocation is carried out, the material to be delivered is placed on the traverse trolley, and the crane is hoisted up.

[0040] The effects of this disclosure will be described in detail below based on the examples, but this disclosure is not limited to these examples.

[0041] (Example 1) Figure 15 shows the equipment specifications. Figure 16 shows the standard table for stacking constraints in the DHCR yard. There are a maximum of seven stacks in the DHCR yard, and the names of the stacks are defined as D1, D2, ..., D7, starting from the traverse trolley side. A maximum of nine slabs can be stacked in one stack. There are a total of three heating furnaces, of which the high-temperature charging furnace is designated as furnace No. 3 (heating furnace number 3). Figure 17 shows the slab attributes and slab location information in the DHCR yard at the time of input information acquisition. Slabs are distinguished by a slab number, which is a unique number for each slab. For example, a slab with slab number 5 is written as slab "5". In this embodiment, the input information is assumed to have been acquired at 15:57:00 on 2022 / 8 / 31. The stacking order of slabs in a stack is such that the bottom layer is 1. For example, in a certain stack, the stacking order of the third slab from the bottom is 3.

[0042] Figure 18 shows information regarding the casting plan at the time of input data acquisition. Here, the finishing code is a code assigned to each slab finishing method. For example, code 60 means "no finishing required, DHCR possible," and code 70 means "partial surface finishing required, DHCR not possible." Figure 19 shows information regarding the hot rolling plan at the time of input data acquisition (corresponding to the initial rolling plan, i.e., the matrix cycle). The "DHCR Direct / Temporary" column is "Direct" if direct material is charged without going through the DHCR yard, "Temporary" if direct material is inserted via the DHCR yard, and blank if it is not direct material. From Figure 19, the current slab condition in the heating furnace can be reproduced through simulation. In addition, the simulation can perform adjustment calculations (calculations to update the initial rolling plan), and adjustment calculations were performed at 90-second intervals in addition to when a new slab arrived at the turner and when a slab was extracted from the high-temperature charging heating furnace.

[0043] The handling of slabs arriving at the turner is determined according to Figure 10. For example, when slab "11" in Figure 18 arrives at the turner, slab "11" is determined to be DHCR-compatible and suitable for interlocking, and its interlocking position is determined. The determination of the interlocking position is performed using Figure 19 and the process shown in Figure 6. The interlocking position is determined similarly for slabs in the DHCR yard in Figure 17. The rolling order for interlocking is determined by prioritizing the slab with the earliest extraction time and following the priority order described above. In this embodiment, since slab "5" in the DHCR yard has the earliest extraction time, slab "11" is determined to be temporarily placed (interlocking position is later than slab "5"), and it is decided that it will be received at pile D1 in the DHCR yard.

[0044] Figure 20 shows an example of a rolling constraint, specifically a constraint on the continuity of the finished thickness of rolled material (an example of a rolling constraint). When the slab to be rolled immediately before the interlocking slab (interlocking material) is designated as the "front material" and the interlocking slab as the "back material," each record in the constraint is searched from top to bottom. If a record is found in the search, it is determined that the constraint is satisfied; if no record is found, it is determined that the constraint is violated and interlocking in that rolling order is not possible. Furthermore, when the interlocking slab is designated as the "front material" and the slab to be rolled immediately after it as the "back material," each record in the constraint is also searched from top to bottom. If a record is found in the search, it is determined that the constraint is satisfied; if no record is found, it is determined that the constraint is violated and interlocking in that rolling order is not possible. The rolling constraints are read, and only interlocking positions that satisfy all rolling constraints are selected.

[0045] Furthermore, to calculate the charging temperature necessary for determining heating and rolling constraints, information on the charging temperature over time, as shown in Figure 14, is read. Here, charging lead time refers to the time from torch cutting to charging into the high-temperature charging furnace. Based on the graph in Figure 14, the temperature at the corresponding charging lead time can be set as the charging temperature.

[0046] Figure 21 shows the rolling plan for the interposition determined by the method described above. It shows the slabs to be interposed, the charging time, and the extraction time. Figure 22 shows the slabs that will be sent to the DHCR yard or the high-temperature charging furnace from among the cast slabs. The "DHCR Direct / Temporary" column allows for the identification of slabs that will be sent to the high-temperature charging furnace and those that will be sent to the DHCR yard.

[0047] (Example 2) While Example 1 created a rolling sequence including interlocking materials, Example 2 shows an example of the output logistics plan. In Example 2, the crane transport plan for executing the interlocking is created as shown in Figure 23. Figure 23 shows the time of issuing the transport plan command, the transport route (work, From, To), and the slab to be transported. The transport plan in Figure 23 includes the information necessary to create commands for temporary storage and unloading at the DHCR yard. By controlling the crane according to Figure 23, interlocking rolling can be performed according to the rolling plan in Figure 21.

[0048] (Example 3) Example 3 shows another example of the output logistics plan. Example 3 considers the case where slabs that have been temporarily stored in the DHCR yard and whose loading schedule has not been determined are returned. In this example, slabs that have been sitting in the DHCR yard and whose loading lead time has exceeded 10 hours are returned to the slab yard. Additional constraints are set to prevent slabs from being temporarily stored on top of slabs that are to be returned. The additional constraint is that no new slabs should be temporarily stored in a pile that contains slabs whose loading schedule has not been determined and whose loading lead time has exceeded 9.5 hours. For example, slab "1" in Figure 17 will have exceeded its loading lead time of 10 hours at 16:06 on 2022 / 8 / 31 and will be subject to return to the slab yard. Figure 24 shows the crane transport plan for the DHCR yard, including the case of returning slabs from the DHCR yard to the slab yard. The items in Figure 24 are the same as in Figure 23. After slab "1" is confirmed as subject to return, the crane is ordered to perform the return operation. Furthermore, no new slabs are temporarily placed in D1, which includes slabs to be returned. By distributing slab "1" onto the traverse trolley according to Figure 24, slab "1" can be returned to the slab yard without interfering with other slabs, etc.

[0049] As described above, the rolling plan creation apparatus 10 and rolling plan creation method according to this embodiment can create a hot rolling plan that guarantees the success of operations through the above configuration and process. By following a rolling plan that guarantees the success of operations, it is possible to avoid operational adjustments due to logistics capacity bottlenecks during actual operations, and efficient steel product manufacturing becomes possible. Furthermore, the created rolling plan is a plan for interim operations that takes into account the logistics plan from casting to rolling. By performing interim operations, it is possible to improve manufacturing efficiency and save energy by suppressing heat dissipation.

[0050] While embodiments relating to this disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art will find it easy to make various modifications or alterations based on this disclosure. Therefore, it should be noted that these modifications or alterations are included within the scope of this disclosure. For example, the functions included in each component or step can be rearranged in a logically consistent manner, and multiple components or steps can be combined into one or divided. Embodiments relating to this disclosure can also be realized as programs executed by a processor in the device or as storage media recording such programs. These should also be understood to be included within the scope of this disclosure. [Explanation of Symbols]

[0051] 10. Rolling plan creation device 11 Acquisition Department 12 Arithmetic section 13 Output section 20 Higher-level systems

Claims

1. A rolling planning device used in the synchronous operation of a steelmaking process using a continuous casting machine and a rolling process in which slabs cast by the continuous casting machine are hot-rolled in a hot-rolling mill, for creating a rolling plan for the hot-rolling process, An acquisition unit that acquires input information including inventory information, casting information, heating information, rolling information, and equipment information, It comprises a calculation unit that performs calculations for creating a rolling plan, The aforementioned arithmetic unit, The rolling plan is created by determining the insertion positions of the direct-shipped materials so as to satisfy the logistics constraints with respect to the initial rolling plan included in the rolling information. Logistical simulations for creating the aforementioned rolling plan determine whether to perform a direct insertion on the slab upon its arrival at the turner or to temporarily store it at the DHCR yard. The aforementioned logistics constraints include the ability to load the directly delivered material into a heating furnace for heating, The determination of whether or not the slab can be loaded into the heating furnace is made based on at least one of the loading status of the traverse trolley that transports the slab to the heating furnace and the operating status of the crane in the temporary storage and heat retention pit provided between the turner and the heating furnace for high-temperature slabs. A rolling planning apparatus in which the logistical constraints are satisfied includes at least one of the following: the traverse trolley being able to load the slab, and the crane being able to dispense the slab onto the traverse trolley.

2. The calculation unit determines the insertion position of the direct material so that the heating constraints are satisfied, The rolling plan creation apparatus according to claim 1, wherein the heating constraints include that the maximum slab width that can be loaded into the heating furnace, calculated based on the heating furnace length, the spacing of slabs in the furnace, the number of slabs in the furnace, and the width of each slab, is equal to or greater than the slab width of the candidate for interlocking, and that the time spent in the furnace is equal to or greater than the minimum time spent in the furnace.

3. The rolling plan creation apparatus according to claim 2, wherein the calculation unit selects the rolling sequence that results in the earliest extraction time from the heating furnace when there are multiple rolling sequences that can be exchanged for the direct-shipped material.

4. The rolling plan creation apparatus according to claim 1 or 2, further comprising an output unit that outputs a logistics plan that satisfies the logistics constraints along with the created rolling plan.

5. The rolling plan creation apparatus according to claim 4, wherein the output unit outputs information about the slab that is returned to the slab yard because the contact pattern has not been determined.

6. The rolling plan creation apparatus according to claim 1 or 2, wherein the calculation unit creates the rolling plan when the slab is extracted from the heating furnace, when the slab arrives at the turner, or when the initial rolling plan is changed.

7. A rolling plan creation method used in the synchronous operation of a steelmaking process using a continuous casting machine and a rolling process in which slabs cast by the continuous casting machine are hot-rolled in a hot-rolling mill, and which is executed by a rolling plan creation device that creates a rolling plan for the hot-rolling, To acquire input information including inventory information, casting information, heating information, rolling information, and equipment information, This includes performing calculations to create a rolling plan, The above operation is, The rolling plan is created by determining the insertion positions of direct-shipped materials so as to satisfy logistics constraints with respect to the initial rolling plan included in the rolling information. The logistics simulation for creating the rolling plan includes determining whether to perform a direct transfer of the slab upon arrival at the turner or to temporarily store it at the DHCR yard. The aforementioned logistics constraints include the ability to load the directly delivered material into a heating furnace for heating, The determination of whether or not the slab can be loaded into the heating furnace is made based on at least one of the loading status of the traverse trolley that transports the slab to the heating furnace and the operating status of the crane in the temporary storage and heat retention pit provided between the turner and the heating furnace for high-temperature slabs. A rolling plan creation method wherein the satisfaction of the logistics constraints includes at least one of the following: the traverse trolley being able to load the slab, and the crane being able to unload the slab onto the traverse trolley.

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