JPH05314140A - Production planning system in batch plant - Google Patents

Abstract

PURPOSE:To dispense with the assistance of an expert, to extend production planning up to production sequence, and to reduce the manhours of configuration of a system. CONSTITUTION:The name of a working device and exclusive time in each process are stored in a product master storage part 11 conforming to a product, and a job generating part 12 generates a job at every device to be used in each process to manufacture the product specified by an order when it is issued, and also, decides the application time of the job, and a job developing part 13 generates a load table 14 by arranging the job on two-dimensional space in which a device name in one direction and a period spanned with prescribed time in the other direction are arranged considering the working device and the application time and an operation ratio monitoring part 15 finds an operation ratio in each period of the device by the load table, and a re-arranging part 16 sets the operation ratio at a value less than a preset value by re-arranging a prescribed job at another spatial position, and a production planning decision part 17 decides the production planning in a batch plant based on the load table.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a product production planning system for a batch plant, and more particularly to a product production planning system for a batch plant that automatically creates an optimum product production plan.

[0002]

2. Description of the Related Art In recent years, with the increase of product types and shortening of production delivery time, the tendency of high-mix low-volume production has been strengthened in the manufacturing industries such as petroleum plants and chemical plants, especially in batch plants. There is. In addition, a batch plant is a plant that manufactures products according to a batch method.When the work of a certain process is completed, the contents of the tank of the current process are transferred to the tank of the next process to perform the next process work. Is to produce.

FIG. 13 shows an example of a batch plant in the chemical industry. As a process, a raw material mixing process, a polymerization process for chemically reacting raw materials, a recovery process for recovering unreacted raw materials, and a product (liquid) obtained by polymerization. ) Is stored in a tank, a drying step of drying a product into a solid material, and a packaging step of packaging a solid material. Each step is provided with several tens of tanks Tij. The work of each process is performed according to a predetermined schedule, and finally the product of the quantity corresponding to the order is manufactured in time for the delivery date.

In such a batch plant, depending on the method of use and the order of use of each device (tank), a large difference occurs in the result of production cost and production time. For this reason,
It is necessary to make an optimal product production plan, and most companies (1) leave the work to a specific expert, and (2) some companies use OR as a schedule problem. Create an optimal production plan using (3) examine the algorithm for each manufacturing site and use the conventional procedural language (Fault Run, Cobol) to build an original system.

[0005]

However, in the first method, since the know-how is concentrated too much on individuals, the know-how is concealed, and the production plan cannot be established without a specialist. .. Further, although the second method can calculate an optimal solution of resource allocation within a rough time, determining a more detailed order of each work requires a huge amount of calculation, which is unrealistic. However, in the third method, it is necessary to individually create each system, which requires too many man-hours / costs, and there is a high possibility that the system needs to be rebuilt due to changes in products / equipment and the like.

[0006] From the above, the object of the present invention is to provide a product production planning method in a batch plant which does not need to rely on a specialist, can perform production planning up to the production sequence, and can reduce the number of system construction steps. That is.

[0007]

FIG. 1 illustrates the principle of the present invention. Reference numeral 11 is a product master storage unit that stores the name of the device used in each process, the occupied time of the device in each process, and the like in order to manufacture the product specified by the order. A job generation unit 13 that generates a job for each device used in each process and determines the submission time of the job is arranged in one direction with the device name and in the other direction with a period spanned by a predetermined time width. A job development unit for arranging the job in the two-dimensional space in consideration of the apparatus used and the time of input, 14 is a load table created by arranging the job in the two-dimensional space, and 15 is arranged at a predetermined position. An operating rate monitoring unit that monitors the operating rate, which is the ratio of the total occupation time of all jobs to the maximum operating time of the apparatus at that position, 16 is a job rate of the jobs arranged in the two-dimensional space Out of which Rearrangement unit for rearranging the job to a different spatial position, 17 load Te was created - a - (g Gantocha) 18 to create a production plan determination unit product production plan in a batch plant based on Bull.

[0008]

The name of the device used in each process and the occupied time of the device in each process are stored in advance in the product master storage unit 11 in correspondence with the product, and when the order is given, The job generation unit 12 generates a job for each device used in each process to manufacture the product specified by the order, and determines the job submission time. The load table 14 is created by arranging each job in a two-dimensional space constituted by a period spanned by a predetermined time width in consideration of the apparatus used and the time of input.
The operating rate monitoring unit 15 obtains an operating rate which is a ratio of the total occupation time of all jobs arranged at a predetermined position in the two-dimensional space and the maximum available time of the apparatus at the position, and the rearrangement unit 16 sets the operating rate. Of the jobs arranged in the two-dimensional space position equal to or more than the value, a predetermined job is rearranged in another space position so that the operation rate is less than the set value, and the production plan determination unit 17 determines the batch plant based on the load table. Determine product production plan. According to this method, it is possible to make a relatively rough production plan in units of time spanned by a predetermined time width (provisional allocation), and to make a detailed production plan in daily units based on the production plan (main allocation), It is not necessary to rely on an expert, and the production plan can be planned up to the production sequence, and further, the system construction man-hours can be reduced. In addition, production planning (load
Bullet), Gantt chart 1 so that the process job of each product is satisfied in the order of the products with the earliest
Since it is arranged on the 8th, a highly accurate product production plan can be performed.

[0009]

【Example】

(a) Overall Configuration FIG. 2 is a configuration diagram of an embodiment of a product production planning system in a batch plant of the present invention, and the same parts as those in FIG. 1 are designated by the same reference numerals. In the figure, 11 is a product master-storing unit for storing the name of the device used in each process, the occupied time of the device in each process, the attribute of the product, etc. in correspondence with the product, and 12 is specified by the order. A job generation unit that generates a job for each input device used in each process to manufacture a product and determines the input time of the job, and the like. 13 is a device name in one direction and a period spanned by a predetermined time width. A job development unit for arranging the jobs in a two-dimensional space in which the jobs are arranged in the other direction in consideration of the device used and the time of input, and a load table created by arranging the jobs in the two-dimensional space. Bull, 15 is an operating rate monitoring unit that monitors the operating rate, which is the ratio of the total occupation time of all jobs placed at a predetermined position to the maximum operating time of the apparatus at that position, and 16 is an operating rate monitoring unit that has an operating rate equal to or greater than a set value. Place in 3D space Rearrangement unit for rearranging the predetermined job to another spatial location of the job,
Reference numeral 17 is a production plan determination unit that creates a product production plan in a batch plant on a daily basis based on the created load table, and 18 is a Gantt chart that expresses the created product production plan, each process in the vertical direction. The two-dimensional space configuration is such that the device names used in step 1 are arranged in order and the date and time are arranged in the horizontal direction, and jobs are arranged at the intersections.

The production plan determination unit 17 refers to the created load table (production plan for temporary allocation), and generates a job queue for generating an allocation sequence (job queue) in the order of products ordered earlier. A creating unit 17a, a constraint queue creating unit 17b that refers to the attribute data of the product, and finds and arranges constraint conditions that must be satisfied in manufacturing the product;
A constraint condition storage unit 17c that stores constraint conditions for each attribute,
A Gantt chart creating unit 17d for allocating jobs (process jobs) of respective orders on the Gantt chart so as to determine a product production plan so as to satisfy the constraint conditions is provided.

The product master stored in the product master storage unit 11 has a data structure diagram shown in FIG. 3, and (1) manufactures a product corresponding to each of the products A, B, ... (2) Number of charges in each process, (3) Occupancy time in each process to manufacture the product, (4) Name of equipment that can be charged in each process, (5) To each charging device The distribution rate (priority) for distributing the occupied time, (6) product attribute data, are stored. It should be noted that the number of charges (the number of divisions of the order batch) and the occupied time are for a predetermined unit amount of product, and the order is given in this unit. Further, the attribute data determines the constraint condition at the time of manufacturing the product and will be described later.

(B) Overall operation job generation When the job generation unit 12 receives an order (including a product name, delivery date, and quantity), the order is generated based on the order and the product master. A job is generated for each input device used in each process to manufacture the product specified by the item d, and the device occupation time and the input date of the job are determined.

The device occupation time of each job can be calculated by multiplying the process occupation time by the device distribution rate, and
The input date is sequentially determined from the job of the subsequent process in consideration of the delivery date, the device occupation time of each process, and the maximum operable time of the device in one day. For example, the delivery date is September 20,
Occupied time of the device used in the final step is 10 hours,
Assuming that the maximum operable time of the device in one day is 12 hours (known), September 19 to which the time obtained by subtracting 10 hours from the delivery date belongs to 12 days is determined as the input date.
If the apparatus occupies 10 hours in the next process, the charging date is similarly determined to be September 18. In addition, the raw material and the like are products used in other processes, and must be produced before the introduction of the product using the raw material. For such raw materials, it is necessary to set the delivery date to the input date of the product using the raw material and determine the input date. ,

As described above, a job is generated for each input device used in the process, and the job information including the device occupation time and the input date of the job is determined. FIG. 4 is a diagram for explaining the jobs, where the product names of the respective orders are A and B and the delivery dates are September 20 and September 22, respectively, and the jobs OD11 to OD11 for each device used in each process. OD14, OD21-OD
26 is generated, and the occupation time, the input date, etc. are determined as the job information.

Job development and load table creation (provisional allocation
The load table 14 is configured to have a two-dimensional space in which device names of all processes are arranged in the vertical direction in the order of processes, and periods spanned by a predetermined time width are arranged in the horizontal direction. FIG. 5 is an example of a two-dimensional space, and monthly periods (upper, middle, late) are arranged in the horizontal direction. At each intersection (box with thick frame), there is a column to enter the total occupied time, maximum available time, operating rate, piled job name, allocation job name. Is becoming The total occupied time is the sum of the occupied time of all jobs placed in the box, and the maximum available time is the maximum time that the device can operate during the period of the box.
The operating rate is a value obtained by dividing the total occupied time by the maximum available time, the pile job is a job arranged (stacked) in the box, and the allocation job is a job finally allocated to the box.

Therefore, the job expanding section 13 stores each job in two.
When arranging in the three-dimensional space, (1) the placement box in the two-dimensional space is decided in consideration of the device used and the time of input of the job, and then (2) the device occupation time of the job is the total occupation time of the relevant box. (3) The job name is registered in the pile job column by adding to (the initial value is zero), so that each job is piled up in each box, and after all the jobs are piled up, (4) The operation rate calculation unit 15 Calculate the operation rate in each box and enter it in the specified column.

As described above, for example, the jobs shown in FIG. 4 are arranged in the two-dimensional space, and the load table shown in FIG.
In other words, the temporary job allocation table is generated. In FIG. 6, the pile job and allocation job columns are omitted, and the maximum operable time of each box is 240 hours (24 hours / day). The period of each box is set to upper, middle, and late, but the accuracy of provisional allocation can be improved by shortening the span of the time width.

When the generation of the rearrangement load table 14 is completed, the rearrangement unit 16 reads the operating rate of each box and checks whether there is a box having a preset value (for example, 100%) or more. If it exists, the job having the lower priority among the jobs arranged in the box is rearranged in another box.

FIG. 7 is a flow chart of the rearrangement process of the rearrangement unit 16. First, it is checked whether or not there is a box whose operating rate is equal to or higher than the set value (step 101), and if there is not, a whole pile job is promoted to an allocation job (step 10)
2) The rearrangement process (temporary allocation process) is completed.

However, if there is a box whose operating rate is equal to or more than the set value in step 101, the priority of jobs piled up in the box is determined (step 103). Priorities are decided by considering the following (1) to (4). That is, (1) work in progress jobs are assigned to the box with the highest priority, and (2) jobs corresponding to products for which the delivery date is specified are likely to have a short allocation target period, and the time selection range is wide. Because it is small, it has a higher priority than jobs of products with no delivery date. (3) Depending on the product, the distribution rate to the device is high, and only certain devices can be used, and the jobs of such products have a high priority, (4) Some jobs are generated for each process according to the product, but if the operating rate of the box to which other process jobs related to the process job whose priority you want to determine belongs is high,
Increase the priority of the job. In (3) and (4), the following equation R = Σ (operating rate / distribution rate) / number of processes is calculated from the operating rate and distribution rate of the box to which each process job according to the product Priority is decided according to size. Then, the piled job with the highest priority is selected (step 104), and the maximum available time of the box ≧ the occupation time of the job ··· (1) is checked (step 105), and if it is satisfied, The target pile job is registered in the allocation job column of the box (step 106).

Thereafter, the occupied time of the job is subtracted from the maximum operable time of the box, the subtraction result is set as the maximum operable time of the box, and the occupied time of the job is calculated from the total occupied time of the box. Subtract and use the result of the subtraction as the total occupied time of the box (step 1
07).

When the updating of the maximum available time and the total occupied time is completed, the operating rate is calculated (step 108), the process returns to the beginning and the subsequent processes are repeated. If the operating rate of the specified box exceeds the set value (100%), step 1
The operation rate is further increased by the processing of 07, and the box becomes the target box again in step 101, and step 101
The subsequent processing is repeated until the maximum available time is exhausted, and equation (1) is no longer satisfied, and unassigned jobs remain in the target box.

In this case, since "NO" is determined in the step 105, another box that can be allocated is selected and registered in the allocated job column (step 109). In other words, the box with a smaller operation rate among the boxes to which the unassigned job belongs (boxes whose operating rate exceeds the set value) and the boxes of other devices that can execute the work of the unassigned job Select (1)
Allocate after confirming that the formula is satisfied. If the equation (1) is not satisfied for all destination boxes, the backward box of the unallocated job is considered.

After allocation, the occupied time of the allocated job is subtracted from the maximum available time of the allocation destination box,
The subtraction result is set as the maximum available time of the allocation destination box, the occupation time of the job is subtracted from the total occupation time of the original box, and the subtraction result is set as the total occupation time of the original box (step 110). .. After that, the operating rate is calculated (step 108), the process returns to the beginning and the subsequent processes are repeated. As a result, the operating rate of all boxes is 100.
If it becomes less than or equal to%, the temporary allocation process ends.

The production plan determination (main allocation) load table 14 stores the temporary allocation position of each job. However, since the temporary allocation is arranged from the job in the post process based on the delivery date and the device occupation time as described above, the jobs are gathered near the delivery date, and the one that is earlier in time (near the production start date) ) Tends to have a margin,
Moreover, there is a possibility that the cleaning time and the constraints before and after the job are not satisfied.

From the above, the production plan determination unit 17 (FIG. 2) attaches importance to the position of each job in the temporary allocation according to the flow chart shown in FIG. Gantt job for manufacturing process jobs
Allocate a book on the platform (creating a Gantt chart). That is, each job (process job) temporarily assigned to the load table is an order to which the job belongs (called an order job).
An order job queue for main allocation is generated on the Gantt chart (step 201), and jobs are sequentially extracted from the order job queue (step 202). If there are no target order jobs, all orders
Assuming that the main job allocation process has been performed, the main allocation process is terminated (step 203). If the target order job exists, a constraint queue for the target order job is created (step 204), and then the target order job is created. -Each process job that constitutes a job is allocated on the Gantt chart (step 20).
5) determine whether all constraint conditions are met (step 20
6) If there is a constraint that is not satisfied, relax the constraint as necessary (step 207), and assign
The processing is repeated so that the constraint condition is satisfied, and thereafter the processing returns to step 202 and the same processing is repeated for the next target order job.

In the temporary allocation, if the operating rate is high and the jobs are concentrated in a certain period and the delivery time is broken, the job group is allocated in advance (to be described later) in the allocation process and is operated. When the rate is low and the allocation space has a margin, the temporary allocation position is emphasized and allocation is performed according to the temporary allocation position.

The job queue creation load table 14 stores the temporary allocation result for each process job. The job queue creating unit 17a represents each job (process job) by the name of the order to which the job belongs (order job), and extracts and arranges the order jobs in order from the box with the earliest input time. -Is created (step 201 in FIG. 8). For example, if the contents of the load table using the order job names A, B, C, D, E, F, G are as shown in FIG. 9, the order jobs are extracted in order from the beginning. Then, the jobs are created by arranging them in the order of delivery date, then extracting the order jobs in the order of middle and late, and arranging them in the order of delivery date. Therefore, in the example of FIG. 9, the delivery date at the beginning is B, C, A, and the delivery date at the middle is D,
E, if the late delivery date is G, F, the job queue is B,
It becomes C, A, D, E, G, F.

Generation of constraint queue Product master-Product master stored in storage unit 11
Contains product attribute data. For example, in FIG.
As shown in, the product master-PMT has a value (A, resident / nonresident, used / unused / not used) according to various attributes (cleaning attribute, resident / nonresident attribute, refrigerant use attribute, etc.) for each product. ··)It is included. On the other hand, the constraint condition storage unit 17
As shown in FIG. 9, the constraint condition extraction rule RSR corresponding to each attribute value and the constraint condition RSC are stored in c.

Therefore, before allocating each process job of a predetermined order on the Gantt chart, the constraint queue creating unit 17
b is an attribute value corresponding to the product of the order, which is a product master-PM.
The constraint condition corresponding to the attribute value is read from T, read from the constraint condition storage unit 17c, and arranged side by side to generate a constraint queue (step 204 in FIG. 8).

Allocation Process FIG. 11 is a flow chart of the process (step 205) of allocating each process job of a predetermined order on the Gantt chart.
The Gantt chart creating unit 17d obtains the process jobs constituting the target order job extracted from the job queue and the device using them (step 301), and then obtains the free time list of each device on the Gantt chart (step 302). FIG. 12 is a diagram showing the relationship between the Gantt chart and the free time list.

Then, it is determined whether the allocation is performed by the left-justification or the left-justification (step 303), and when the allocation is performed by the left-justification, the process jobs are sequentially allocated from the upper process of the target order job to the idle time (step 30).
4) It is checked whether each constraint condition of the constraint queue is satisfied (step 305), and if not satisfied, the rearward free time is reallocated so as to satisfy the constraint condition (step 306). Then, it is checked whether all process jobs have been allocated (step 307), and if the allocation of all process jobs is completed, the main allocation process for one order job is completed. The process of is repeated. Note that the next process job has the end time of the previous process job as the start time, and when the process job is moved by the constraint condition, the constraint condition is checked by going back to the upper process.

On the other hand, when the allocation is carried out by the last-justification, the process jobs are sequentially allocated from the lower process of the target order job to the vacant time (step 308), and the constraint queue is added.
It is checked whether each constraint condition (1) is satisfied (step 309), and if it is not satisfied, reallocation to the forward free time is performed again so that the constraint condition is satisfied (step 31).
0).

Next, it is checked whether all process jobs have been allocated (step 311), and if the allocation of all process jobs is completed, the main allocation process for one order job is completed, and if not completed, the next higher process is executed. Step 30
The processing from 8 onward is repeated. When the preceding process job has the start time of the subsequent process job as the end time and is moved by the constraint condition, the constraint condition is checked by going back to the lower process. If all the constraint conditions cannot be cleared, the constraints are removed from the constraint queue in the order of weak constraint conditions so that the allocation is successful.

Summarizing the operation of the product production planning system shown in FIG.
When the order is given by pre-storing the name of the device used in each process, the occupied time of the device in each process, the attribute data, etc. in advance in the product master storage unit 11 in association with the product. The job generation unit 12 generates a job for each device used in each process for manufacturing the product specified by the order, and also determines the device occupation time and job input time of the job.

The job development unit 13 arranges each job in a two-dimensional space constituted by a device name and a period spanned by a predetermined time width in consideration of the device used and the time of input, and loads the job.
Bull 14 is created. The operating rate monitoring unit 15 obtains an operating rate which is a ratio of the total occupation time of all jobs arranged at a predetermined position in the two-dimensional space and the maximum available time of the apparatus at the position, and the rearrangement unit 16 sets the operating rate. Of the jobs arranged in the two-dimensional space position equal to or larger than the value, a predetermined job is rearranged in another space position so that the operating rate is set to the set value or less. ... Temporary allocation

When the temporary allocation is completed, the production plan determination unit 17
Emphasizes the provisional allocation position of the load table, allocates process jobs for manufacturing the ordered products on the Gantt chart in order of the order of the earliest input time, and plans the product production in the batch plant. To decide.
... More book allocation

[0038]

As described above, according to the present invention, a relatively rough production plan is made for each period spanned by a predetermined time width, and a detailed production plan for each day is made based on the production plan. Therefore, it is not necessary to rely on an expert, and the production plan can be made up to the production sequence, and further, the man-hours for constructing the system can be reduced.

Further, according to the present invention, since the process jobs of each product are arranged on the Gantt chart so that the constraint conditions are satisfied in the order of the products having the earliest loading time in the load table, the accuracy of the accuracy is improved. High product production planning can be done.

Further, according to the present invention, it is possible to prepare a feasible schedule plan in a short time for a problem having a complicated process such as a batch plant and severe restrictions. Moreover, if the user's restrictions are increased, it is possible to construct a system with more severe restrictions and a planning result containing more user's know-how.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a configuration diagram of an embodiment of the present invention.

FIG. 3 is a data configuration diagram of a product master.

FIG. 4 is a diagram illustrating a job.

FIG. 5 is an explanatory diagram of a two-dimensional space of a load table.

FIG. 6 is an explanatory diagram of a load table.

FIG. 7 is a flowchart of a rearrangement process.

FIG. 8 is a flowchart of a production plan determination process.

FIG. 9 is an explanatory diagram of a job queue.

FIG. 10 is an explanatory diagram of a constraint queue.

FIG. 11 is a flowchart of an allocation process.

FIG. 12 is a relationship diagram between a Gantt chart and a free time list.

FIG. 13 is a process explanatory diagram of a batch plant.

[Explanation of symbols]

 11-Product master-storage unit 12-Job generation unit 13-Job development unit 14-Load table 15-Operating rate monitoring unit 16-Relocation unit 17-Production plan determination unit 18- Gantt chart

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Ishikawa 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Zeon Co., Ltd. (72) Minoru Inuzuka 1-2-1, Yokou, Kawasaki-ku, Kawasaki-shi, Kanagawa No. ZEON Corporation (72) Inventor Koji Aragaki 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Fujitsu Limited

Claims (3)

[Claims] 1. In a product production planning method in a batch plant for manufacturing a product through a plurality of processes, the name of the device used in each process and the occupied time of the device in each process are stored in association with the product. The job is generated for each device used in each process to manufacture the product specified by the step and order, and the job input time is determined based on the occupied time of the device and the delivery date of the order. A step of deciding, a step of arranging each job in a two-dimensional space in which device names are arranged in one direction and periods spanned by a predetermined time width are arranged in the other direction, in consideration of the device used and the time of input. A step of obtaining a two-dimensional spatial position having an operating rate which is a ratio of a total occupation time of all jobs arranged at a predetermined position and a maximum operable time of the apparatus at the position, the two-dimensional space position; Relocating a predetermined job among the jobs arranged in the position to another space position to reduce the operating rate to a set value or less, and a product production plan in a batch plant based on the rearranged load table And a step of determining a product production planning method in a batch plant. 2. The step of deciding the product production plan determines the allocation order using the load table in the order of earliest input time, and a job for manufacturing the product of each order according to the order. 2. The product production planning method in a batch plant according to claim 1, wherein the product production planning is determined by allocating to the Gantt chart. 3. A product attribute is stored in association with each product, and product manufacturing constraint conditions are defined in association with the attributes, and jobs are placed on the Gantt chart so that the constraint conditions are satisfied. The production planning method for a product in a batch plant according to claim 2, wherein