JPH08287149A - Production planning generating method - Google Patents

Abstract

PURPOSE: To generate a production planning of a plant which has processes including branching and returns by setting a unit whose time frame has a constant value and giving the unit time order in facility line units, and adjusting the difference in load time between a unit which is currently in process and a unit of next time of a next process. CONSTITUTION: Operation schedule information by production lines and days as units is registered as input data (step 100) and passing reference days by processes which are measured from the date of delivery are calculated (step 102). Then the schedule days of the foremost process products A and C to be passed and a product B are determined at to a line A and a line B respectively according to the passing reference days (step 104), and the schedule days of the respective processes are determined in the order from the 2nd process to the final process on the basis of the foremost process schedule days by the products in consideration of the distribution lead time between processes. When there is an express progress material to be processed preferentially to ordinary processes, a man adjusts the schedule days (step 108).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a production plan, and in particular, a production plan capable of systematically producing a product manufactured through complicated steps such as branching and returning. It is about how to create.

[0002]

2. Description of the Related Art Generally, in a production plan of a plant which manufactures products through a plurality of processes, the required amount and schedule of an intermediate process are determined on the basis of the required amount and schedule of a final process.

At this time, as proposed in Japanese Patent Laid-Open No. 6-52175, a process control unit time is set, the processing time is captured by an integral multiple of this time, and an integer multiple of this process control unit time is used in the future. The elapsed time is delimited, and in the near future, this integer is set to a small value to manage finely, and in the far future,
A process control method that sets this integer to a large value and roughly manages it, grasps and predicts the process status such as the movement of goods and the estimation of equipment load for each division, and suppresses production based on this is considered. Has been.

According to this process control system, there is no branching or returning and it is effective for a simple plant in which the product flows in one direction.

[0005]

On the other hand, there are complicated processes in which branching and returning exist, for example, there are multiple lines of equipment having the same function, and there are different steps such as intermediate steps and final steps with the same equipment. In a plant that is processed, it is difficult to set a schedule for each facility unless the waiting time between processes (lead time L / T) is accurately determined. We couldn't improve the prediction accuracy and the schedule was insufficient,
There were problems such as material deficiency, increase in work in progress, unachieved and exceeded plan for throughput.

The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to make it possible to create a highly accurate production plan even in a plant having a complicated process including branching and returning. And

[0007]

According to the present invention, in a production planning method of a plant for manufacturing a product through a plurality of steps, units having a fixed time frame are set, and each unit is set as a time unit for each equipment line. In order to prevent the processing order from being reversed, the load time is received and paid between the unit currently in process and the unit in the next time of the next process, and the load time is accumulated in each unit The above object is achieved by determining the load time and the treatment amount of the above, and making a schedule collectively for the materials having the same treatment conditions according to the material constitution in each unit.

[0008]

In the present invention, a unit whose time frame has a constant value is set, and each unit is provided in the equipment line unit in the order of time, and the load is placed between the unit currently in process and the unit at the next time of the next process. Since the time is paid and received, even in a complicated process including branching and returning, the processing order is not reversed and a highly accurate production plan can be made.

Further, the load time is accumulated in each unit to obtain the load time and the processing amount of each unit, so that the load time and the processing amount of each unit can be accurately predicted. it can. Therefore, it is possible to optimize the operation plan of each line, reduce the amount of work in progress before each line, and prevent unplanned suspension. Further, by improving the accuracy of the completion date of each material, it is possible to prevent shipment (delivery date) delay.

Further, since the materials having the same processing conditions are put together by the material composition in each unit, rational production without waste can be performed.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

In this embodiment, for example, as shown in FIG. 1, two pretreatment lines A-1 and A-2, which have basically the same function and are arranged in parallel, and two pretreatment lines, which are also arranged in parallel, are provided. Belt grinding lines B-1 and B-2, four rolling lines C-1 to C-4 also arranged in parallel, and three annealing lines D-1 to D-3 also arranged in parallel. The annealing lines D-1 to D- are applied to a production plant for steel products having two refining lines E-1 and E-2 that are also arranged in parallel.
Part of the product that has gone through any of No. 3 is returned to either the belt grinding line B-1 or B-2, and the other of the products that has also gone through any of the annealing lines D-1 to D-3. The section includes a returning step of returning to any one of the rolling lines C-1 to C-4.

Therefore, this plant has two branched pretreatment lines A- for carrying out essentially the same pretreatment.
1 and A-2, branched belt grinding lines B-1 and B-2 for basically performing the same belt grinding, and four branched rolling lines for basically performing the same rolling. Line C-
1 to C-4, 3 branching annealing lines D-1 to D-3 for basically performing the same annealing, and 2 branching lines for basically performing the same tempering treatment. Heat treatment line E-
1 and E-2 are included.

Returning from any of the annealing lines D-1 to D-3 to any of the belt grinding lines B-1 and B-2 or any of the rolling lines C-1 to C-4. Since there is a product that flows into any one of the annealing lines D-1 to D-3 again, the annealing lines D-1 to D-3 are the intermediate steps (1
It has two kinds of functions: the second time) and the final process (second time).

The production plan in this embodiment is shown in FIG.
It is performed according to the flow chart as shown in FIG.

That is, in the first step 100, operation schedule information for each process (line) and for each day which is a unit of the embodiment is registered as one of the input data. The registration frequency can be set, for example, once a month, but it can be corrected at any time due to external factors such as occasional fluctuations in orders and fluctuations in material supply. An example of registration is shown in FIG. In this embodiment, one unit is set from 7:00 am to 7:00 am on the next day. Therefore, for example, the A line on September 1 will be shut down for construction from 7:00 to 11:00, and 2
From 3 o'clock to 3 o'clock the next morning, it indicates that the line is stopped due to "vacant team" with no people on the line. Lines B and C on September 1 and lines A to C on September 2 all indicate 24 hours of operation.

Next, in step 102, the process-based plate passing reference date, which is delayed from the delivery date, is calculated. As shown in FIG. 4, which shows one of the input data, that is, the required amount of processing, the passing process differs for each product. For example, in FIG. 4, product A is line A
And C, product B passes lines B to D, and product C passes lines A to D. Therefore, for each product,
Delivery date (September 10 for products A and B, September 11 for product C)
Day) to calculate the reference date for passing each process. Here, the passing date is calculated by the following formula, for example.

Sheet passing reference date = delivery date−Σ (sheet passing lead time for each sheet passing step) (1)

Here, the threading lead time (L / T) for each passing of the threading step is pre-input as shown in FIG. 5 as one of the input data, for example.

FIG. 6 shows an example of the data (conversion program data) of the plate passing reference date for each product obtained by using the equation (1).

Then, the process proceeds to step 104 and step 1
For the earliest step (the line A for products A and C, the line B for product B) calculated by 02 for each product, the planned date is determined according to the plate passing reference date. At that time, the planned date is automatically determined if it is on the standard date, but the standard date is already in the past, the plan is passed in advance to prepare for future line suspension, and the line processing capacity If there is a margin, the preceding passage and the like can be set as a planned date different from the reference date by a human instruction. The "A line" in FIG. 7 shows an example of conversion program data in which the planned date of the earliest process is determined according to this step, and further, the processing time of the earliest process (A line in this case) is tabulated for each planned date. .

Then, the process proceeds to step 106 and step 1
Based on the earliest process plan date for each product determined in 04, considering the physical distribution lead time between each process, the planned date of each process in order from the second process to the third process ... decide. The determined planned date is in the format shown in Fig. 6,
The date is partly shifted. Examples of the conversion program data processed in step 106 are "B line" to "D line" in FIG. In this example, similar to the case of the A line, the result of totalizing the processing time for each planned date is shown.

Next, in step 108, when there is an express progress material to be processed prior to the normal process, a person adjusts the planned date in consideration of this planned date. Specifically, it is checked whether the final process planning date for each product determined in step 106 satisfies the delivery date. We will examine the possibility of late delivery products, extract the express progress materials that can not be delivered late, accelerate the earliest process planning date, and shorten the logistics lead time between each process as emergency transportation,
The steps 104 and 106 are repeated to adjust the production date to the production date on time.

Next, in step 110, the load time is accumulated in a unit for each process (a fixed time frame to be the lead time, for example, in units of 1 day), and the accumulation calculation for all the plate passing processes is executed. Specifically, step 104 described above.
Based on the planned date for each product determined in ~ 108, the load time accumulation calculation is performed for each planned date for all the processes of the strip products, considering the processing capacity and operation schedule that differ depending on the line. A line with a processing capacity (line operating time> load time) or a line calculated to exceed the processing capacity (load time> line operating time) is extracted, and if there is a corresponding line, steps 104 and 106 are repeated,
Adjust so that the plan is consistent with the processing capacity and operation schedule of each line. Figure 7 shows the adjusted state.
Is.

Here, the load time accumulated in the unit is calculated for each product and each process by the following equation.

Load time = Product mass / (Processing amount per unit time of the process) (2)

In this embodiment, the product quantity is the product mass, but it may be the product quantity.

Next, various constraints are checked on the basis of the accumulated calculation result. Specifically, step 11
In step 2, it is determined whether the processing amount of each process by planned date does not exceed the processing capacity of each process by planned date. In step 114, it is determined whether the express progress material satisfies requirements such as delivery date.
In step 16, it is determined whether or not the lead time constraint between each process is satisfied, and in step 118, it is determined whether or not the inventory amount limit (inventory constraint) of each process is satisfied, and in step 120, each process, especially the neckline. To determine if the productivity is maximized. If the determination result in step 120 is negative, the materials having the same processing conditions are put together in the material configuration in each unit to improve productivity.

If the result of the determination in step 120 is positive, the process proceeds to step 122, and it is determined whether or not the final process planning date is before the final process passing reference date.

If any of the judgment results of steps 112 to 122 is negative, the process returns to step 104 again,
Readjust the plan.

If the result of the determination in step 122 is positive, the process proceeds to step 124, and the established production plan is finally and comprehensively evaluated. From the viewpoint of evaluation, there are roughly three points: production volume, inventory volume, and delivery rate achievement rate. Figure 8
It shows the transition of inventory by line and by planned date for the inventory quantity which is one of the evaluation targets.

In the above embodiment, the time unit is set to one day, and the present invention is applied to the steel product production plant, but the length of the time unit and the object to which the present invention is applied are not limited to this. .

[0033]

As described above, according to the present invention,
Since the accuracy of load prediction is improved, each line operation plan is optimized, the amount of work in progress before each line is reduced, and resources can be saved. Further, it is possible to reduce energy loss in line operation due to unplanned suspension. Further, by improving the accuracy of the completion date of each material, it is possible to prevent the production user from delaying the production activity or the confusion due to the shipment delay.

[Brief description of drawings]

FIG. 1 is a process diagram showing a production process of a steel product production plant, which is an example of an application target of the present invention.

FIG. 2 is a flowchart showing a processing procedure of an embodiment for creating a production plan according to the present invention.

FIG. 3 is a diagram showing an example of line-by-line operation information that is one of input data when creating a production plan.

FIG. 4 is a diagram showing an example of a required processing amount which is one of input data.

FIG. 5 is a line diagram showing an example of a strip running lead time for each strip running process which is one of input data.

FIG. 6 is a diagram showing an example of a plate passing reference day which is also one of conversion program data.

FIG. 7 is a diagram showing an example of a line-by-line processing amount which is also one of conversion program data.

FIG. 8 is a diagram showing an example of line-by-line stock quantity which is one of output data.

[Explanation of symbols]

 A-1, A-2 ... Pretreatment line B-1, B-2 ... Belt grinding line C-1-4 ... Rolling line D-1-3 ... Annealing line E-1, E-2 ... Tempering line

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masuo Tasaka 1-50 Asanagi-cho, Nishinomiya-shi, Hyogo Kawatetsu Information System Co., Ltd. Headquarters office (72) Inventor Ko Nishikawa 1-50 Asagi-cho, Nishinomiya-shi, Hyogo Prefecture Kawatetsu Information System Co., Ltd. Head Office

Claims (1)

[Claims] 1. A method for producing a production plan for a plant that manufactures products through a plurality of processes, in which units having a fixed time frame are set, and each unit has a unit in the order of time, and the processing order is In order not to reverse, the load time is received and paid between the unit currently in process and the unit at the next time of the next process, and the load time is accumulated in each unit to obtain the load time and the throughput of each unit. A production plan creation method characterized in that materials having the same processing conditions are put together in a schedule according to the material composition in each unit.