JP2007179519A - Method and device for creating production plan - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for creating a production plan, in which a plan for producing each of production lots through a plurality of production processes can be formed in an optimum manner. <P>SOLUTION: The method comprises reading data from a storage means storing data related to a plurality of production lots differed in lead time length of production process, producing the plurality of production lots differed in lead time length in one or more processing facilities, extracting production lots satisfying a preset restriction condition related to production order, selecting an optional lot from the extracted production lots while relatively reducing, when a production lot having a lead time length longer than a predetermined time is included in the extracted production lots, the probability of selecting a production lot with a longer lead time, to determine the production order, and determining time information of the production processes of the production lot based on a preset restriction condition related to time to form a production schedule. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a production plan creation method and apparatus for creating a plan for producing a variety of production lots through a plurality of production steps.

  Conventionally, steel production production plans depend on the production lot delivery time, processing constraints in each process, the components of the steel type of the production lot, and the amount of components in order to improve productivity, reduce manufacturing costs, and manufacture high-quality products. Based on the process constraints, the skilled person determines the processing timing through trial and error. That is, an expert in planning determines the manufacturing order so as to satisfy the delivery date while observing the constraints on planning. However, due to the increase and strictness of the constraints on the production order accompanying the increase in the production steel types and high quality products, the load when the skilled person makes a plan is increasing. For this reason, when formulating a plan, attention tends to be paid only to satisfying the constraints, and the optimality of the created plan is often insufficient. In view of this, a method for automatically formulating a plan and achieving optimality has been proposed (see, for example, Patent Document 1).

In this prior art (Patent Document 1), a continuous casting set (casting by connecting a plurality of converter charges) of a production lot that satisfies the constraints related to the manufacturing order is extracted, and the continuous casting set has already been determined. A cast set is continuously obtained as a candidate from the state of an empty (non-operating) position in the converter with the cast set. The above processing is repeated to determine the manufacturing order for one day, and the time information of the casting set is determined continuously based on the time-related constraints, thereby creating a manufacturing schedule. When the manufacturing schedule satisfies the evaluation standard (primary evaluation), it is set as a production plan candidate. Then, a predetermined number of candidates are created, and an optimal one is selected based on the evaluation criteria (secondary evaluation).
JP 2000-315109 A

  In the above-mentioned Patent Document 1, a continuous cast set of a production lot that satisfies the constraints related to the manufacturing order is extracted, and an empty position (unoperated) in the converter between the continuous cast set and the predetermined continuous cast set. If a continuous casting set that can fill the vacant position is obtained as the next candidate from the time zone) and this process is repeated to determine the manufacturing order for one day, the following problem occurs. In this case, it is considered that different continuous cast sets are not manufactured in the same time zone in all the subsequent facilities including the steel output in the converter.

  FIG. 9 is a diagram showing a boundary state when a manufacturing Gantt chart is created. In the case where there is a free time C in the converter process in the figure, in order to increase the operating state of the converter, it is rational in terms of production efficiency to create a plan by filling the position of C, which is an empty position. Is. The continuous casting set that can be arranged at the position C is a continuous casting set (09Z) with a long lead time cast by the equipment of casting 1 as shown in FIG. This is because if the continuous casting set has a long lead time, the processing after the converter tends to be delayed, so there is a probability that the manufacturing time zone will overlap even if the same equipment is used with the continuous casting set whose schedule has already been determined. Because it is low. Conversely, continuous casting sets with short lead times have a higher probability of overlapping in the same equipment in the lower process (especially the casting process). As a result, there is a tendency that the probability of selecting a continuous casting set having a long lead time becomes higher. In the figure, the alphanumeric characters before the start of casting are the ID numbers of the casting set. Here, the continuous casting set to be planned is composed of, for example, eight. In this example, the continuous cast sets cast by the casting facility 1 are 09Z, L258, 01Y, and L005, and the continuous cast sets cast by the casting facility 2 are 04Y, 03Y, 07Y, and 03Z. A normal continuous casting set is processed by the refining equipment 3, 4 or 6. 09Z is processed by refining equipment 1-2-4-3 and requires processing of 4 equipment. It is a continuous casting set with a longer lead time from converter to casting compared to other continuous casting sets.

  When continuous casting sets with long lead times and short continuous casting sets are mixed, even if it is arranged so that no extra free time is generated in the converter process, free time is required in the casting process. Become. In the casting process, the casting time of a continuous casting set is completed, and the idle time for the next continuous casting set to start casting is an operation referred to as equipment setup work, which is a predetermined time or longer (for example, 50 minutes or 1 hour) is required. As a result, time may be spent even in the steelmaking process in the converter. In this way, in Patent Document 1, the order of steel output is determined without considering the length of the lead time of the continuous casting set (manufacturing lot). On the other hand, there are continuous casting sets having different lead times during casting. When the operating rate of the converter is increased in a mixed state, and the casting set is continuously arranged from the empty position of the converter, FIG. 10 of the Gantt chart created by the conventional method shows the state of A (in the converter). A large waiting time) occurs.

  In addition, the continuous cast set arranged next to 09Z is a continuous cast set cast by a casting facility different from 09Z (usually, there are few material sources for the continuous cast set having a long lead time). For example, when a continuous casting set of 04Y having a short lead time is arranged, the position of the continuous casting set is determined in consideration of the casting setup time for casting 2, so that the state A in the figure occurs. As shown in FIG. 10, the continuous casting set 09Z is arranged, and the next continuous casting set is selected by setting up a time corresponding to the setup time B so that the casting 2 does not compete and the refining equipment does not compete. A free time is generated in the converter. Moreover, the only continuous casting set that can be arranged at the position C in FIG. 9 is 09Z, and the other seven continuous casting sets cannot be arranged in C. For this reason, the problem that the converter idle time of A of FIG.

  The present invention has been made to solve the above-described problem, and a production plan creation method capable of optimally creating a plan for producing a production lot through a plurality of production steps, and An object is to provide such a device.

The production plan creation method according to the present invention is a production plan creation method for creating a plan for producing a variety of production lots through a plurality of production steps, and a plurality of productions having different lead times in the production process. Constraints related to a preset manufacturing order by reading data from storage means storing data related to lots, manufacturing a plurality of manufacturing lots having different lead times using one or a plurality of processing facilities If a production lot satisfying the conditions is extracted and the extracted production lot includes a production lot whose lead time is longer than a predetermined time, the production lot having a long lead time Is set in advance by selecting an arbitrary production lot from the extracted production lots and determining the production order. To determine the time information of the production lot of the manufacturing process to create a production schedule based on the constraints applied between.
In addition, the production plan creation method according to the present invention includes a single converter, a plurality of refining facilities, and a continuous casting facility, and creates a plan for producing a variety of production lots through a plurality of production processes. In the production plan creation method, a first step of reading data from a storage means in which data relating to a plurality of production lots having different lead times from the converter to the continuous casting equipment is stored, and the data is read in the step. A second step of extracting a production lot that satisfies the constraints related to the production order from a plurality of production lots set in advance, and the length of the lead time is predetermined for the production lot extracted in the step If a production lot with a longer lead time is included, the probability of selecting a production lot with a long lead time is relatively low, and the extracted lot is extracted. A third step of selecting an arbitrary production lot from the production lots, determining the production order of the plurality of production lots by repeating the second step and the third step, and relating to a preset time Based on the constraint conditions, time information of the manufacturing process of the manufacturing lot is determined and a manufacturing schedule is created.
Further, in the production plan creation method according to the present invention, the length of the lead time varies depending on the number of facilities through which the production lot passes and / or the processing time at the refining facility of the production lot.
Further, in the production plan creation method according to the present invention, when a production lot having a long lead time is selected, the continuous casting equipment is different from the production lock having the long lead time, and a plurality of production lots are provided. Combine with production lots with short lead times that are connected and configured.
In the production plan creation method according to the present invention, the production lot with the short lead time has a casting time longer than the total time of the casting time and the setup time of the production lot with the long lead time. is there.

The production plan creation device according to the present invention includes a single converter, a plurality of refining facilities and a continuous casting facility, and a production for creating a plan for producing a variety of production lots through a plurality of production processes. In the plan creation device, storage means for storing data relating to a plurality of production lots having different lead times from the converter to the continuous casting equipment, and a first treatment for reading data relating to the production lots from the storage means; A second process for extracting a production lot that satisfies a restriction condition relating to a preset production order from the plurality of read production lots; and a lead time for the production lot extracted in the second process. If a production lot whose length is longer than the specified time is included, the probability of selecting a production lot with a long lead time is relatively low, A third process for selecting an arbitrary production lot from the extracted production lots is performed, and the second process and the third process are repeated to determine the production order of the plurality of production lots. And calculating means for determining the time information of the manufacturing process of the manufacturing lot based on the constraint condition relating to the current time and creating a manufacturing schedule.
The “preset time” of the present invention is the following time when determining the start and end times of production lots in each facility, and considers the following (1) and (2) It is a thing.
(1) Converter for each production lot (continuous casting set), refining equipment, casting processing time, and transfer time between equipments (2) Setup time for the same refining equipment (equipment interval time), continuous at each casting equipment Casting set-up time (casting interval)
Further, in the present invention, the following two points are factors that lead to a long lead time from the converter to the casting equipment.
(1) There are many refining facilities through which production lots pass from the converter to the casting facilities.
(2) There is one refining facility through which the production lot passes from the converter to the casting facility, and it takes time to move (pan transport time) when processing with a specific refining facility. For example, it is in a location far away from a certain refining facility.

  As described above, in the present invention, a plurality of manufacturing lots having different lead times are manufactured by one or a plurality of processing facilities, and manufacturing lots satisfying the constraints related to the preset manufacturing order are extracted. If the extracted production lot contains a production lot with a long lead time, the relative probability of selecting a production lot with a long lead time is selected from the extracted production lots. The production order is determined by selecting an arbitrary production lot and determining the time information of the production process of the production lot based on the constraints related to the preset time. As a result, the probability of selecting a production lot with a long lead time is reduced, and as a result, the adverse effect that the converter free time is inevitably generated as in the past can be avoided, and the optimum It is possible to automatically develop. For this reason, an operator's load can be reduced.

Embodiment 1. FIG.
FIG. 1 is a block diagram showing a configuration of a production planning apparatus according to Embodiment 1 of the present invention. The factory production management computer is composed of a host computer 10 and includes a production plan database determined based on orders and factory operating conditions, a product casting plan database for determining manufacturing contents, a master database for manufacturing standards, and the like. These databases constitute storage means of the present invention. The production plan database is data including information such as orders, components, quantities, delivery dates, equipment downtime, etc. The product casting plan database is the components of each production lot, passing process, size (width, thickness, etc.), The master database is data including information on the manufacturing conditions, the slab cutting position, and the like, and the master database includes information on the converter, each refining equipment, each casting processing time, and the moving time between equipment. In addition, a production plan of a production lot to which specific time information is added is created on a distributed computer (not shown) such as a personal computer. The material data and master data necessary for creation are transmitted from the host computer 10 to the planning computer 20. The planning computer 20 constitutes the computing means of the present invention.

The production plan of the production lot created by the planning computer 20 is returned to the host computer 10 and becomes a manufacturing instruction to each factory. The host computer 10 and the distributed computer are connected via a LAN, a dedicated communication line, or the like, so that data can be transmitted and received. The material data is data having information on each charge of the production lot, and includes, for example, the following items.
1) Charge ID number (identification number for identifying each charge)
2) Continuous casting set number
3) Continuous casting set order (indicates the order in which the charge is located in the continuous casting)
4) Width, thickness
5) Casting equipment
6) Delivery date (customer delivery date or estimated date of converter steelmaking obtained retroactively from customer delivery date)
7) Refining equipment passing process
8) Processing start and end times for each facility (time information added to the planned charge up to the previous day)

  FIG. 2 is a conceptual diagram of the continuous casting set of the present invention. A continuous casting set of production lots is a series of sets that are processed by flowing into the refining equipment and continuous casting equipment in the pan after the blowing process in the converter is completed, and pass through the converter, refining equipment, and continuous casting equipment. Has process information. In addition, the line segment of the horizontal part of FIG. 2 represents processing time, and the inclined line segment represents movement time. In the example of FIG. 2, the converter is an example of 2 charges, but depending on the production lot, there are cases where it becomes 1 charge, 3 charges, etc.

FIG. 3 is a flowchart showing a procedure for creating a plan according to this embodiment.
The planning computer 20 acquires planned material sources up to the previous day and material source data to be planned for the day before starting the processing of FIG. For the material data subject to the same day plan, the data corresponding to a predetermined number of days after the delivery date (scheduled date of steelmaking for the converter calculated retroactively from the customer delivery date) is extracted from the material data. And get.

  The planning computer 20 selects a candidate for a continuous casting set to be arranged next from the material sources to be planned on that day based on the planning state up to the previous day (the previous day). At this time, as a candidate that can be arranged in a portion where there is a free time in the converter, a continuous casting set in which the refining equipment and the casting equipment do not compete with each other is selected. These equipment competition conditions are determined based on the master (constraint conditions) (STEP 1). Here, the “planned state until immediately before” represents a continuous casting set with time information on the left side of FIG. Actually, there is a plan for 24 hours on the further left side (not shown) of FIG. 9, and the start of continuous casting set is started on the previous day. Without changing the position of these continuous cast set parts, select one material source (material source without time information) to be planned for the day, and satisfy the time-related constraints To determine the position on the schedule. In addition, the determination of whether or not there is free time, from the start and end of each converter of the continuous casting set to which time information is added, the "end time of the previous converter" next to the converter on the time axis The difference from the “next converter start time” is determined to be vacant with a threshold of several minutes or more, and the next continuous casting set converter is replenished to the vacancy.

That is, the idle time Δt (i) of each converter is calculated by the following formula.
Δt (i) = {converter start time of (i + 1) -th continuous casting set} − {i-th continuous casting set
Converter end time} (1)
Then, it is determined that the casting set is continuously replenished because there is a free time when Expression (2) is satisfied.
Δt (i)> th (predetermined time) (2)

In addition, the equipment competition conditions determine time information (start time and end time of equipment) so as to satisfy the following (3) and (4).
(3) Do not treat each equipment (converter, refining equipment, casting equipment) at the same time.
(4) Refining equipment and casting equipment require setup time (equipment interval).
Note that the setup time indicates a time zone in which the processing is interrupted in the continuous casting as shown in FIG.

  Next, the planning computer 20 determines whether or not there is a continuous casting set selected as the above-mentioned candidate (step 101). If there is no candidate, the process proceeds to step 105, and the process proceeds to the next available time. On the other hand, if there is a candidate, it is determined whether the continuous casting set having a long lead time and the short continuous casting set are mixed, that is, whether the continuous casting sets having different lead times are mixed. (Step 102). Here, whether the lead time is long or short may be determined by the number of refining facilities through which the selected candidate continuous casting set passes. For example, a continuous cast set that passes through only one refining facility may have a short lead time, and a continuous cast set that passes through two or more refining facilities may be determined to have a long lead time. Whether there is a continuous casting set having two or more refining facilities is defined in the item of the refining facility passing process of “material data” as to which refining facilities are used. For example, in the continuous casting set of 09Z in FIG. 10, there is information on the passing process of equipment 1-equipment 2-equipment 4-equipment 3, and based on this information, it can be seen that the four refining equipment is passed through. Judgment is based on the information.

  If only a short continuous casting set is used, the process is the same as that of the prior art, and the process proceeds to STEP2. On the other hand, when a continuous casting set having a long lead time is included as a candidate, a selection probability process using the selection probability Ps is executed (step 103). In step 103, the material source selection probability Ps is a preset value, and it is determined whether or not to select based on this value. Here, the material source selection probability Ps is a continuous casting with a long lead time defined by the lead time being longer than a predetermined time in the next time position (time position on the schedule). It is a numerical value for reducing the probability that the set is selected from a plurality of consecutive cast sets. That is, as described above, a continuous casting set having a long lead time is a condition that easily satisfies the constraint condition, and thus tends to be a candidate. On the other hand, if the selection is made too much, a free space is likely to occur. Therefore, the priority is lowered in order to prevent selection more than necessary. As a result, the converter free space state such as “A” in FIG. 10 is not generated.

  The Ps is in the range of 0 to 100%, for example, several tens of percent, and is set so as to be selected with the lowest possible probability. If there is no candidate for a continuous casting set having two or more refining facilities, one continuous casting set is selected from them. Here, when selecting from candidates, a random number from 1 to 100 may be generated and a candidate corresponding to the selection probability range including the value may be selected. For example, if there are four candidates and the continuous casting set has a short lead time, the continuous casting sets A, B, C, and D are set to 1/4 of the same selection probability (= 25%). ), 1 to 25 are assigned to A, 26 to 50 are assigned to B, 51 to 75 are assigned to C, and 76 to 100 are assigned to D. Then, for example, if 45 is obtained from the random number generation value, B corresponding to the range of 25 to 50 is selected. Conversely, when A is a continuous casting set with a long lead time, for example, the selection probability of B, C, and D remains 25%, A is 10%, and the remaining 15% is any of A to D. Suppose that it is not selected. In this case, if it corresponds to 15% in which none of A to D is selected, the next converter free time zone on the schedule time is assigned to the target converter free time without assigning a continuous casting set. Transition to target processing. Alternatively, the selection probability of A is 10%, and other B, C, and D are 30%, and 1 to 10 are assigned to A, 11 to 40 are assigned to B, 41 to 70 are assigned to C, and 71 to 100 are assigned to D. As a result, the probability that A will be selected is another third, and it is difficult to select A. Also, if the selected item is only a continuous casting set with a long lead time, it is determined whether or not to select it, the selection probability is set to 20%, for example, and the random number value is 1 to 20 is selected, but if it is 21 to 100, it is not selected. As a result, it is possible to make it difficult to select continuous casting sets having a long lead time. In this way, it is possible to set the number of consecutive cast sets having a long lead time to an appropriate value.

  If any of the candidates processed and extracted in STEP 1 is selected as the processing result of STEP 103 (Step 104 / Yes), the process proceeds to STEP 2 and none of them are selected (Step 104 / No). In the idle time zone of the converter steel that has been examined, the casting set is not replenished (allocated) continuously, and the next free zone time zone (incrementing i described above, Δt (i + 1)) The process proceeds to the target process (step 105).

  The basis for determining the threshold value of the Ps parameter is determined by the following investigation. As shown in FIG. 4, it is effective to examine the rate at which 09Z occurs at the same position when the selection probability is changed, and to select the material source selection probability such that the occurrence frequency is about several tens of percent. . In the example of FIG. 11 described later, this is a case where Ps is 5%. (In FIG. 10, Ps is equivalent to 100%, because the length of the lead time is not taken into consideration when selecting).

  The planning computer 20 performs the same processing as that described in Patent Document 1 after the above processing. In a plurality of continuous casting set groups selected in the above-described process, the overlapping degree between each candidate converter and the already disposed converter is calculated (STEP 2). As shown in FIG. 5, for example, when any example of candidates 1 to 3 is given, the overlap state is that each candidate 1 to 3 has been selected 2 and overlapped in the converter. Suppose that the sum for each candidate for the part is divided by the number of charges in the continuous casting set of candidates. Specific overlaps of candidates 1 to 3 are expressed by equations (5) to (7).

(Overlapping condition of candidate 1) = (total of converter wrap portion 1) / 3 (5)
(Overlapping condition of candidate 2) = (total of converter wrap part 2) / 3 (6)
(Overlapping condition of candidate 3) = (total of converter wrap portion 3) / 1 (7)

  Next, the degree of overlap of all candidate converters is calculated, and the upper M pieces are left in order from the smallest degree of overlap, and one is selected from the M pieces using, for example, random numbers (STEP 3).

  Here, if the given material source and all the continuous casting sets are selected, the process proceeds to STEP5. If the material source remains, the target is shifted to the next converter free time, and the process returns to step 1 to search for the next candidate, and from step 1 to step 4 until all the material sources (for one day) are exhausted. The calculation process is continued (STEP 4). For example, when case 2 is selected in the example of FIG. 5, the candidate 2 continuous casting set becomes the selected continuous casting set 3, and all material sources for one day except for the already selected material sources. The above calculation process is repeated in the same manner until is selected.

  Next, the planning computer 20 determines the steel start time of the converter, the processing start time at the refining equipment, and the processing start time of the continuous casting equipment based on the order of the continuous casting set (STEP 5). At this time, the respective start times are determined so as to satisfy the following constraint conditions. If the following constraint conditions cannot be satisfied simply by adjusting the processing start time of each equipment in the entire cast set unit, the processing start time is delayed in the refining equipment. That is, the constraint condition is satisfied by adjusting by giving a waiting time until the processing is started.

[Restrictions for determining the processing start time]
・ Lap removal in converter ・ Refining equipment lap removal ・ Continuous casting maintenance ・ Casting interval ・ Steeling time designation material

  FIG. 6 is a view showing an example of converter wrap removal. 6A shows that when a continuous casting set is arranged in order from the continuous casting sets 1 to 3, an attempt is made to insert the continuous casting set 2 converter between the continuous casting set 1 converter and the converter. However, since the interval is shorter than the processing time of the converter, the portion of the converter wraps as shown by the arrow ↓. Similarly, the same applies when the continuous casting set 3 is placed after the continuous casting set 2. For this reason, as shown in FIG. 6B, in order to eliminate the converter lap and maintain the casting continuously, a waiting time (□ in the figure) is given before the start of the refining equipment. To create a practical schedule. In FIG. 6B, only the continuous casting sets 1 to 3 are shown, but at this stage, the continuous casting sets for one day are selected.

After the planning computer 20 determines the sequence of casting sets and the processing start time of each facility,
-Number of cups in the converter-Waiting time at the refining equipment-If the time at which the specified steel output time is within the allowable range given in advance, it will be a candidate for the plan result solution. If any of the above three conditions is not satisfied, the process returns to STEP 1 and the order of successive casting sets is determined again (STEP 6: primary evaluation).

  The planning computer 20 determines whether or not the number of solution candidates for the planning result is a predetermined number (STEP 7). If the number is the predetermined number (in this case, a timing chart for one day is displayed). A predetermined number will be completed.), It progresses to STEP8. . Otherwise, return to STEP1.

The planning computer 20 evaluates whether the plan result solution candidates are, for example, the following: • Variety balance • Balance in a predetermined time unit • Refining equipment balance is within a predetermined range It selects as a result and makes it a schedule result (STEP8: secondary evaluation). The selection of the optimum plan result may be performed automatically or by the operator's selection. Here, the variety balance is a balance of production amounts of different varieties such as thin plates, thick plates, pipes, etc., and the balance in a predetermined time unit is, for example, in units of 8 hours when the unit is 8 hours. It is the balance of equipment utilization rate, steel output, etc. The refining equipment balance is for grasping the uniform operation of a plurality of refining equipment, and is excluded when each refining equipment is not operating uniformly.

  One manufacturing schedule candidate is completed by the series of processes described above. Further, a predetermined number (for example, 1000 or 10,000) of production schedule patterns is created, and, for example, an optimum production schedule having the largest number of steel-making cups, for example, based on the number of steel-making cups. Is determined as the production schedule for the day.

  As described above, in the present embodiment, a plurality of continuous casting sets having different lead times are manufactured using one or a plurality of processing equipments, and continuous casting satisfying the constraints related to the preset manufacturing order. When a set is extracted and a continuous casting set with a long lead time is included in the extracted continuous casting set, a production lot with a long lead time is selected from the extracted continuous casting set. The process order is determined by selecting an arbitrary continuous cast set with a relatively low probability, and the time information of the continuous casting set manufacturing process is determined based on a preset constraint on time. Since the production schedule was created, the probability that continuous casting sets with long lead times were selected was reduced, and as a result, there was an adverse effect that the converter idle time was always generated as in the prior art. Avoidance can, it is possible to automatically develop an optimal plan.

  In addition, although the above-mentioned embodiment is an example about continuous casting, this invention is not limited to it, and if it is what produces many kinds of manufacturing lots through several manufacturing processes, respectively, it is object. It becomes.

Embodiment 2. FIG.
In the first embodiment, the example in which the production order is determined by relatively reducing the probability of selecting continuous casting sets having a long lead time has been described. An example in which a cast set is selected and a continuous cast set with a long lead time and a short continuous cast set coexist will be described as a second embodiment.

  FIG. 7 is an explanatory diagram showing an example of a case where a continuous casting set having a long lead time and a short continuous casting set are mixed. In the example of case 1 in FIG. 7, when a continuous casting set with a long lead time (A-1) and a continuous casting set with a short lead time (B-1, A-2) are combined, the continuous casting set of A-2 is By taking the setup time for casting in the same continuous casting equipment 1 as the continuous casting set of A-1, the idle time of the converter is generated. Similarly, in the case of the case 2, unlike the case 1, in the continuous casting set of B-2 which is cast by the continuous casting facility 2, the time required for the converter is generated in order to take the setup time of the continuous casting facility 2. It will be. FIG. 13 shows a specific plan example of case 2. In cases 1 and 2 of FIG. 7, the converter free time is generated by combining a continuous casting set (A-1) with a long lead time and a continuous casting set (B-1) with a short lead time. Even if A-2 manufactured by the same continuous casting equipment 1 and B-2 manufactured by the continuous casting equipment 2 are arranged in a continuous casting set thereafter, it is not possible to eliminate the empty space in the converter.

  Therefore, in the second embodiment, when a continuous casting set with a short lead time is combined with a continuous casting set with a long lead time (A-1), the casting is performed with different continuous casting equipment, for example, B-3. In addition, the number of converter cups is large (multiple production lots are connected), and it is longer than the combined time of “casting time in continuous casting equipment 1 and setup time of continuous casting equipment 1”. This is dealt with by combining casting sets with continuous casting time. That is, when a continuous casting set (A-1) with a long lead time is the target of planning, a continuous casting set such as B-3 is prepared at the same time to prepare a plan, thereby freeing up the converter. prevent. As shown in a specific plan example, as shown in FIG. 11 described later, it is possible to prevent the converter from being vacant by combining with a continuous casting set of Y04.

As an embodiment of the present invention, an example of creating a subsequent schedule from the boundary state of FIG. 9 will be described with reference to the flowchart of FIG. First, let us consider a case where there are six consecutive cast sets as shown in FIG. The breakdown is divided into the following three patterns of continuous casting sets according to the passing process: (A) 2 pieces, (B) 2 pieces, and (C) 2 pieces.
(A) Converter → No. 3 refining → No. 1 casting (B) Converter → No. 1 refining → No. 2 refining → No. 4 refining → No. 3 refining → No. 1 casting (C) Converter → No.6 refining → No.2 casting

  Among these, the continuous cast set (B) is a continuous cast set having a long lead time because it passes through a plurality of refining facilities. Fig. 9 shows that (B) pattern continuous casting set extends from the refining equipment to No. 1 casting, and (C) pattern continuous casting set extends from converter to No. 2 casting from the previous day. It is assumed that the line is shown. First, a search is made for the idle time in the converter steel that has the earliest time, and “C” in FIG. 9 is extracted. In the following explanation, first, the procedure of the process of continuously replenishing the casting set to “C” will be explained.

  First, in STEP 1 of FIG. 3, candidates that can be assigned to the position C are extracted. For example, in FIG. 9, if an attempt is made to put the pattern (A) in the “C” position, equipment competition with the pattern (B) from the previous day occurs in No. 1 casting, and thus it is not extracted as a candidate. Next, when the pattern (B) is put into “C”, there are competing in the refining and casting equipment, so they are extracted as candidates. Next, the (C) pattern is not extracted as a candidate because the refining or casting equipment competition occurs in the (C) pattern that continues from the previous day. As a result, the continuous casting set having the conditions that can be assigned to the position of “C” becomes two patterns (B).

  In this state, if the process goes to step 101, there is a candidate, and the process proceeds to step 102. Since a continuous casting set with a long lead time is included, the selection process with the selection probability Ps is performed at step 103. Here, as described above, since only continuous casting sets having a long lead time are included, the selection probability thereof is set low, and as a result, the continuous casting sets may not be selected. If a continuous casting pattern is selected, step 104 is YES and the process proceeds to STEP2. The subsequent processing in this case is the same as that of the prior art (Patent Document 1). On the other hand, if not selected, a continuous casting set is not assigned to the position of “C”, but the idle time is left as it is, and the process of considering the continuous casting set assignment in the next empty time zone is entered. .

  In the method of the prior art (Patent Document 1), since the casting set is always assigned to the idle time, the continuous casting set having a long lead time is assigned to “C”. Then, among 1000 or 10,000 production patterns that are repeatedly created, a production pattern in which casting sets are not continuously assigned is also created at a ratio corresponding to the set selection probability.

  A case where no casting set is continuously assigned in the above “C” will be described below. The next free time zone to be examined next is “D”, although the free time is short. No candidates for “D” were selected when “C”, so six remained. In the case of “D”, unlike “C”, even if all consecutive casting sets are arranged, equipment competition in refining and casting does not occur, so all are extracted as candidates (STEP 1). Thereafter, the processing from step 101 · Yes to step 102 · No to step 103 to step 104 is performed in the same manner as described above. In this case, one of the patterns (A) to (C) (step 104 · Yes) or none of the patterns (step 104 · No) is selected, and four arrangement cases occur probabilistically.

  “D” has a short vacant time zone, but when the selected continuous cast set is placed in the converter steel, “C” to “C” are used because the “C” position is vacant. Since the process of “D” can be operated by moving forward in time, the process is changed so as to be moved on the schedule, and is arranged at the “D” position. In the present invention, it is possible to create a production schedule to be arranged in “D” without being arranged in “C”. On the other hand, in the prior art, since only a fixed manufacturing schedule in which continuous casting sets having long lead times are always arranged at the position “C” can be created, variations in manufacturing patterns are limited.

  FIG. 11 shows an example of creating a plan by the method of the present invention which is not arranged in such “C”. FIG. 10 shows an example of a plan created by the conventional method. In the “C” position, a continuous casting set having a long lead time is arranged. As a result, the converter free time and casting As a result, only about 41 cups can be obtained per day (7:30 to 7:30 on the next day). On the other hand, in the present invention, a manufacturing schedule comparable to that of the prior art can be obtained, but a manufacturing schedule not arranged in “C” can be created. FIG. 11 shows an example in which a large number of outgoing steel cups are selected from a large number of production schedules, and 43 outgoing steels can be output. According to the method of the present invention, it is possible to create a plan in which a long converter free time is eliminated and the number of outgoing steel cups is increased by two.

  In this embodiment, in order to avoid the state of A in FIG. 10, the positional relationship between 09Z and 04Y can be arranged as shown in FIG. 11, and 09Z is cast by casting 1. In FIG. 11, in order to fill the converter position, the one with a large number of charges in the casting set is arranged so that the casting end of 04Y cast in casting 2 is after the end of casting of 09Z. This is an example.

It is the figure which showed the structure of the production plan preparation apparatus which concerns on Embodiment 1 of the structure of this invention. It is a conceptual diagram of a continuous casting set. It is the flowchart which showed the process of production plan preparation. It is the characteristic view which showed the relationship between material source selection probability and occurrence frequency. It is the figure which showed the example which searched the continuous casting set which can be arrange | positioned from the next of the planned schedule from the production lot of the plan object. It is the figure which showed the example of the lap removal of a converter. It is explanatory drawing when the continuous casting set with a long lead time is selected. It is explanatory drawing of a plan object material source. It is a figure showing the boundary state at the time of creating a manufacturing Gantt chart. It is the figure which showed the example of plan preparation by a prior art. It is the figure which showed the example of plan preparation by this invention. It is the figure which showed the example of plan preparation of the example which sets up setup time in this invention. It is the figure which showed the example of plan preparation when there is converter free time.

Claims (6)

In a production plan creation method for creating a plan for producing a variety of production lots through a plurality of production processes,
One or a plurality of processing facilities for reading a plurality of production lots having different lead times by reading the data from storage means storing data relating to a plurality of production lots having different lead times in the manufacturing process A production lot that satisfies the constraints related to the preset production order is extracted, and the extracted production lot includes a production lot whose lead time is longer than a predetermined time. In this case, the probability of selecting a production lot having a long lead time is relatively low, and an arbitrary production lot is selected from the extracted production lots to determine the production order, and is set in advance. A production plan creation method, comprising: producing a production schedule by determining time information of a production process of a production lot on the basis of a constraint condition relating to a given time. In a production plan creation method comprising a single converter, a plurality of refining facilities and a continuous casting facility, and creating a plan for producing a variety of production lots through a plurality of production processes,
A first step of reading the data from a storage means in which data relating to a plurality of production lots having different lead times from the converter to the continuous casting facility are stored;
A second step of extracting a production lot satisfying the constraints related to the preset production order from the plurality of production lots read in the step;
When the production lot extracted in the above process includes a production lot whose lead time is longer than a predetermined time, the probability that a production lot having a long lead time is selected is relatively low. And a third step of selecting an arbitrary production lot from the extracted production lots,
The second step and the third step are repeated to determine the manufacturing order of the plurality of manufacturing lots, and the time information of the manufacturing process of the manufacturing lot is determined based on the constraint conditions related to the preset time. A production plan creation method characterized by creating a schedule.   3. The production plan creation method according to claim 2, wherein the length of the lead time varies depending on the number of facilities through which the production lot passes and / or the processing time at the refining facility of the production lot. When a production lot with a long lead time is selected,
The continuous casting equipment is different from the long production time production lock and is combined with a short production time production lot constituted by connecting a plurality of production lots. Production plan creation method.   5. The production according to claim 4, wherein the production lot with the short lead time has a casting time that is longer than the total time of the casting time and the setup time of the production lot with the long lead time. Planning method. In a production plan creation device, which comprises one converter, a plurality of refining facilities and a continuous casting facility, and creates a plan for producing a variety of production lots through a plurality of production processes,
Storage means for storing data on a plurality of production lots having different lead times from the converter to the continuous casting facility;
A first process for reading data relating to the production lot from the storage means; and a second process for extracting a production lot satisfying a restriction condition relating to a preset production order from the plurality of read production lots. If the production lot extracted in the second process includes a production lot whose lead time is longer than a predetermined time, the probability that a production lot having a long lead time is selected is selected. And a third process of selecting an arbitrary production lot from the extracted production lots, and repeating the second process and the third process to produce the plurality of production lots. Computation means for determining the order and determining the time information of the production process of the production lot based on the constraints related to the preset time and creating a production schedule Production planning apparatus according to claim.

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