JP3360638B2 - Casting operation plan formulation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for creating a schedule for a tapping date for each casting set in a series of steelmaking processes in which continuous casting is performed through a converter and a secondary refining process.

[0002]

2. Description of the Related Art In the steelmaking process in the steel industry,
After the steel is discharged from the converter, the steel is processed by one or more secondary smelting facilities determined for each type of steel to be produced, and then cast by a continuous casting facility.

[0003] The planning of each day from the planning frame for several days is performed manually by a skilled operator, and the balance between the required date of tapping of the type of product to be produced, the load on the secondary refining equipment, and the type of product to be cast. It is created while taking into account.

[0004] As a specific example of a method for automatically creating a casting schedule plan up to several days in the future, Japanese Patent Application Laid-Open No. H6-126436 has proposed a casting plan creation support system for casting with a stationary mold. ing. In this method, a load calculation is performed for each core machine with respect to a casting plan created by the knowledge processing, and the casting plan is corrected based on the result to improve the accuracy.

The configuration is based on a means for temporarily determining a casting date and the number of castings for each product up to several days ahead for each product with reference to a manufacturing lead time on a daily demand basis, and a casting lot summarizing knowledge in a knowledge data section. Means for determining the casting date and the number of castings by assembling the casting lots with reference to the temporary casting date and the casting number data for each product. Further, a process-specific load such as a load man-hour for each core machine for the casting schedule data for each product determined by the means is displayed for each casting date, and the casting schedule is corrected in an interactive manner based on the load man-hour. Characterized by comprising:

[0006] Further, as a specific example of a plan in consideration of a time axis in a steelmaking process including a converter, a secondary refining facility, and a continuous casting machine, an operation schedule of molten steel distribution is disclosed in Japanese Patent Application Laid-Open No. 9-235610. A system has been proposed. This is based on the continuous casting schedule,
An operation schedule that takes into account distribution interference can be easily and accurately created.

As a procedure, based on the casting schedule of the continuous casting machine, the time axis and the process are traced from the casting process to the upper process. Considering the first step of tentatively determining the operation schedule and the blowing schedule of the steelmaking process obtained from the first step, the downstream The method is characterized in that the second step of verifying the effect of the processing steps on the operation schedule and recalculating the operation schedule is combined.

[0008]

In formulating a casting operation plan, creating a plan for several days is important information in formulating an operation plan for a lower process after casting.
This is necessary in formulating work plans for rolling, surface treatment, and the like in the lower process. It is also important in reducing inventory in slabs and billets.

[0009] In order to meet these demands, it is necessary to consider the load of the secondary refining equipment and the balance of the type of casting from the given few days (about one week) of the material source, and determine the date of request for tapping. Each sunrise steel plan that is as satisfying as possible is needed.

As a method for automatically creating a casting schedule plan up to several days in the prior art, a casting plan creation support system for casting with the above-mentioned stationary mold has been proposed. There was no scheduling.

As described above, since the plan for each schedule is not determined from the plan frame up to several days ahead, the time axis up to several days ahead in the steelmaking process up to the converter, the secondary smelting facility, and the continuous casting machine is set. A plan that takes into account could not be formulated.

Further, in order to formulate a plan for each schedule from a plan frame up to several days in advance, a continuous casting set in which the load distribution of the bottleneck equipment and the type distribution request date for tapping is limited.
When there are many types of casting widths and diameters, differences in casting time for the same converter (difference), differences in the number of continuously cast cups, differences in the number of cast sets that can be processed in a day, etc. Must be considered. In such a case or when casting a special steel type, it must be taken into consideration that a continuous casting set of a predetermined steel type needs to be processed before and after processing the continuous casting set. However, the prior art could not meet these demands. If time information is forcibly taken in without considering these requirements, there has been a problem that physical distribution interference and changes in the operation schedule frequently occur when planning the time information.

The present invention has been made in order to solve such problems, and it has been made possible to plan an optimum tapping date for each casting set and to automate a production plan. The purpose is to provide a planning method.

[0014]

The above-mentioned object is achieved by the following invention.

According to a first aspect of the invention, there is provided a casting operation plan formulation method for preparing an operation schedule of a steelmaking process having a converter, a secondary refining facility, and a continuous casting machine. A first step of determining the type balance of the casting and the load condition of the secondary smelting equipment, a second step of determining the state of the type of the casting to be cast each day, and the load state of the secondary smelting equipment on each day. The third step to be judged, the judgment result of the second step and the third step, the date of request for tapping of the cast set,
A fourth step of successively moving or exchanging casting sets is sequentially performed to formulate an operation plan for several days.

According to the present invention, in the first step, the number of charges, the type balance, and the load condition of the secondary smelting facility are determined from a plan frame for several days. At this stage, the operation plan is still in a tentative decision stage, but the first step makes it possible to handle a plan frame for several days as an optimization target.

Next, in a second step and a third step, it is determined whether the kind to be cast and the number of casting sets in the secondary refining equipment are excessive or insufficient. In the fourth step, the number of types and the number of charges of the secondary refining equipment are determined in advance in accordance with the result of these determinations, that is, the combination of the excess or deficiency of the type to be cast and the excess or deficiency of the continuous casting set in the secondary refining equipment. The casting set is moved or replaced one after another so that it falls within the set range.

In this way, by repeating the second to fourth steps, the excess or deficiency of the variety and the excess or deficiency of the continuous casting set in the secondary refining equipment are successively eliminated, and a plan for several days is obtained. The casting operation plan can be optimized for the frame.

According to a second aspect of the present invention, in the fourth step, the continuous casting set, the continuous casting length,
And determining whether or not to plan on the same day based on a combination with another casting set.

The present invention specifies a method for selecting candidates for successively moving and replacing cast sets in the fourth step. First, if the tapping request date is limited, another candidate is searched. In addition, a continuous casting set in which the sum of the processing time of continuous casting and the preparation time of casting is within 24 hours is selected. Further, a combination with another continuous casting set is also considered.

For example, when the selected continuous casting set is sent to the previous day's plan, the remaining continuous casting sets which cannot be processed because they are to be cast in combination with the continuous casting set are not available. appear. In such a case,
Search for other candidates by leaving the cast set. In this way, it is possible to reduce distribution interference and changes in the operation schedule.

The third invention is characterized in that, in the fourth step, the steel casting set is moved or replaced with respect to the desired tapping date of the continuous casting set within a predetermined schedule deviation. It is a casting operation plan formulation method of the first or second invention.

According to the present invention, the movement and replacement of the cast sets are limited to a schedule close to the desired tapping date. Actually, first, the transfer / replacement is attempted on the schedule before and after the steel tapping request date, and if not possible, the schedule is as close as possible to the schedule before and after that. In this way,
Casting can be performed as close as possible to the date of tapping as much as possible, and it is possible to optimize the casting operation plan for several days.

According to the present invention, in the above-mentioned fourth step, the continuous casting set is moved or replaced within a predetermined schedule deviation with respect to the required tapping date. Therefore, the difference between the requested date and the planned date (the steel tapping date) can be suppressed within a preset range.

A fourth invention is a method for formulating an operation plan for casting according to the first to third inventions, wherein a plan for an operation plan for several days is created from the first day or the last day.

According to the present invention, a plan is created through the first to fourth steps sequentially from the first day or the last day.
Since the plan is created sequentially from the first day or the last day, the operation plan is also determined in order of the schedule, and when the final day or the first day is determined, the operation plan for several days is determined.

As described above, in the operation schedule creation system for the steel making process having the converter, the secondary refining equipment, and the continuous casting machine, the number of charges for each day, the type balance to be cast, the secondary balance, Determine the load conditions of the refining equipment, determine the state of the type of casting to be cast on each day and the load state of the secondary refining equipment, and formulate an operation plan for several days that takes into account the date of request for tapping of the type of product to be produced. . This makes it possible to accurately plan work such as rolling and surface treatment in a lower process, and to reduce inventory in a slab or billet state.

Further, in the steelmaking process up to the converter, the secondary refining facility, and the continuous casting machine, a planning frame for each schedule is determined in consideration of load distribution and product distribution of bottleneck facilities. Furthermore, a continuous casting set with a limited tapping date is required. If there are many types of casting widths and diameters, the casting time in the same converter is different. The number of continuous casting sets that can be processed in a different manner, or when casting a special steel type, it is necessary to process a continuous casting set of a predetermined steel type before and after processing the continuous casting set, etc. A planning frame is determined. In this way, it is possible to formulate a plan that takes into account the time axis up to several days in advance, and also to formulate a plan that reduces distribution interference and changes in the operation schedule.

[0029]

FIG. 1 is a flowchart showing an embodiment of the present invention. In FIG. 1, in STEP1, a first step of determining the number of charges for each day, the type balance to be cast, and the load condition of the secondary smelting facility from a planning frame for several days is performed. Hereinafter, in STEP2, a second step of judging the state of the type of casting to be performed on each day, and in STEP3, a third step of judging the load state of the secondary refining equipment on each day.

Thereafter, in STEP 4, a fourth cast set is continuously moved or replaced in consideration of the judgment results of the second step and the third step and the request date of tapping of the continuous cast set.
Is carried out. In addition, when moving or exchanging successive cast sets, preferably, a continuous cast set in which the tapping request date is limited, and a continuous cast set length, and one continuous cast set is combined with another continuous cast set on the same date. Consider planning.

The specific processing of each step (STEPs 1 to 4) and the end condition of each day will be described below. Here, the types that become bottlenecks in planning will be described as types A and B, and the secondary refining equipment will be described as R1 and R2.

First step (STEP 1): Each kind, secondary refining equipment, and the average number of charges for each day are calculated. Confirm that the average of secondary refining equipment is below the maximum processing capacity. Temporarily arrange the given material source according to the tapping request date.

Second step (STEP 2): In this example, a plan for the n-th day is formulated one day at a time from the last day (N day) of planning the material sources allocated for each steel tapping request date. I will do it. For example, the corresponding state of (A type, B type) on the nth day is calculated from the table shown in Table 1. A for n days
Varieties, each of the total number of charges X _A and B varieties of X _B states are defined as follows.

The shortage: X _A <A ₁ ,Tekisetsu:A ₁ ≦X _A ≦A ₂ ,Kajo:X _A> A ₂ missing: X _{B <B 1, suitable: B 1 ≦ X B ≦ B} 2, excess: X _B > B ₂ Here, A ₁ , A ₂ , B ₁ , and B ₂ are constants that determine an allowable range of the appropriate number of charges.

[0035]

[Table 1]

Third step (STEP3): A plan for the nth day is formulated one day at a time from the last day (Nth day) of planning the material sources allocated for each steel tapping request date. For example, the corresponding state of (R1, R2) on the nth day is calculated from the table shown in Table 2. Here, the states of the total charge numbers X _R1 and X _R2 of R1 and R2 on the nth day are defined as follows.

The shortage: X _{R1 <R1 1, appropriate: R1 1 ≦ X R1 ≦ R1} 2,
Excess: X _{R1> R1 2} missing: X _{R2 <R2 1, suitable: R2 1 ≦ X R2 ≦ R2} 2, excess: X _R2> R2
_{2 where, R1 1, R1 2, R2} 1, R2 2 is a constant that determines the appropriate number of charges tolerance.

[0038]

[Table 2]

Fourth step (STEP 4): As shown in Table 3, cases are classified as shown in the following (1) to (3) due to excess or deficiency of varieties, and further classified according to excess or deficiency in the refining route. Then, the process of selecting and replacing the casting set is performed successively. Here, the selectable sets are targeted for sets in which the number of charges in the set is the same or within a predetermined range (± m charges). Hereinafter, the details will be described.

[0040]

[Table 3]

(1) When one or both varieties of A and B are excessive (Table 3 "Excess varieties"):
If either or both of R1 and R2 on day n are excessive (Table 3 “Route excess”), select a continuous casting set with refining routes from A and B to R1 and R2, and n-1 day To the plan. If one or both of R1 and R2 on day n are insufficient or appropriate (see Table 3 "Route shortage"
Or, select a continuous casting set having a refining route other than R1 and R2 on the nth day, and then proceed to the n-1th day plan.

(2) When one or both of the varieties are insufficient (Table 3 “insufficient varieties”):
If either or both of R1 and R2 on the nth day are excessive, a continuous casting set with refining routes other than R1 and R2 from A and B on the n-1th day is selected, and the plan for the nth day is made. Also, n days
From A and B, select a continuous casting set with R1 and R2 refining routes and make a plan for the n-1 day, select a continuous casting set with a refining route other than R1 and R2 from the n-1 day plan, and n Make a plan for the day.

If one or both of R1 and R2 on day n are insufficient, a continuous casting set having a refining route of R1 and R2 on day n-1 is selected. If R1 and R2 on day n are appropriate, a continuous casting set having a refining route other than R1 and R2 on day n-1 is selected.

In each operation, if there is no set corresponding to the (n-1) th day, a similar selection is made from the (n-2) th day.

(3) When the amounts of A and B are appropriate (Table 3
“Appropriate variety”): In this case, if either or both of R1 and R2 on day n are excessive, start from A and B on day n-1
Select a continuous casting set with a refining route other than R1 and R2, and n
A refining route having R1 and R2 is selected from the n-day plan, and the n-1 day plan is selected.

If one or both of R1 and R2 on the nth day are insufficient, a continuous casting set having a refining route other than R1 and R2 from A and B on the nth day is selected. As a plan, a refining route having R1 and R2 is selected from the plan for the n-1 day, and the plan for the n day is made.

In each operation, if there is no set corresponding to the (n-1) th day, a similar selection is made from the (n-2) th day.

As described above, in the fourth step (STEP 4), the casting sets are successively replaced according to the above (1) to (3). Preferably, as shown in FIG. The determination is made based on the combination with the continuous casting length and another continuous casting set. This means that, after confirming the following three conditions, the operation of exchanging n-1 days (n-2 days ...) and n days is performed as follows.

If a continuous casting set with a limited tapping date is selected and the continuous casting set moves to another scheduled date, another candidate is searched for.

The total of the processing time of each continuous casting and the casting preparation time is calculated for each continuous casting set, and the continuous casting set in a case where the total of one day on n days is within 24 hours is selected.

When the planned date of the selected continuous casting set changes, if there is an unprocessable continuous casting set for the remaining same planning date, another candidate is searched for.

End determination: After executing the fourth step as described above, here, a determination is made as to the end of the n-day plan creation. After the second to fourth steps, the condition for ending the creation of the plan for the nth day is a case where both the product type and the refining route have become appropriate.

(A type, B type) = (appropriate, appropriate) (R1, R2) = (appropriate, appropriate) When it is determined that the process is completed by the end condition, the process returns to STEP2, and the calculation is performed for the (n-1) th day. I do. If the termination condition is not satisfied, repeat Step 2 and later for n days.

The end of the plan for the entire schedule (several days) is the first day (n = 1 day), and ends when the above-mentioned end condition is satisfied.

As another embodiment, in STEP 4 in FIG. 1, a continuous casting set may be moved or exchanged within a predetermined schedule deviation with respect to a tapping request date. In this case, n-1
When selecting a continuous casting set from day or n-2 days, a continuous casting set that satisfies the condition of the following equation in addition to the condition of STEP4 is selected.

| Desired date−planned date | ≦ K Here, the constant K is an allowable value of the difference between the planned date and the desired date.

As yet another embodiment, as shown in FIG. 2, an operation plan may be created from the first day. In this case, in the above description, the first day (n = 1) and the last day (N) are exchanged, and n-1 day is replaced with n + 1 day, and n-2 day is replaced with n + 2.
It may be replaced with a day and executed in the same manner. Table 3 changes to Table 4 by this replacement.

[0058]

[Table 4]

[0059]

According to the present invention, a converter, a secondary refining facility,
In an operation schedule creation system for a steelmaking process with a continuous casting machine, the number of charges for each day, the balance of the type to be cast, and the load conditions of the secondary refining equipment are determined from the planning frame for several days, and the While judging the condition and the load condition of the secondary smelting equipment, it is possible to formulate an operation plan for several days in consideration of the date of request for tapping of the product to be produced. As a result, an accurate work plan such as rolling and surface treatment in a lower process, and a reduction in inventory in a slab or billet state can be achieved.

Further, in the steelmaking process up to the converter, the secondary refining equipment, and the continuous casting machine, the schedule frame for each schedule is determined in consideration of the load distribution and the kind distribution of the bottleneck equipment. In addition, the planning frame for each schedule is determined in consideration of the limitation of the steel tapping request date, the number of successive casting sets that can be processed in one day, or the combination of steel types of successive casting sets, etc. Considering the axis, a plan can be formulated to reduce logistics interference and changes in operating schedules.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing another embodiment of the invention.

FIG. 3 is a view showing another embodiment for a fourth step.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-9-235610 (JP, A) JP-A-10-235540 (JP, A) JP-A-62-296611 (JP, A) JP-A-62-96611 164811 (JP, A) JP-A-9-249903 (JP, A) JP-A-2000-176634 (JP, A) JP-A-6-126436 (JP, A) JP-A-2000-126862 (JP, A) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) B22D 11/16 C21C 5/28 C21C 7/00

Claims (4)

(57) [Claims] 1. A casting operation plan formulation method for creating an operation schedule of a steelmaking process having a converter, a secondary refining facility, and a continuous casting machine, the number of charges for each day from the planning frame for several days, the type of casting A first step of determining the load conditions of the balance and the secondary smelting facility, a second step of determining the state of the type of casting to be cast on each day, and a third step of determining the load state of the secondary smelting facility on each day. And the fourth step of successively moving or exchanging the casting set are sequentially executed, and the results of the judgments of the second step and the third step are successively performed. A method for formulating an operation plan for casting, comprising formulating an operation plan. In a fourth step, it is further determined whether or not it is possible to plan on the same day based on a combination with a continuous casting set, a continuous casting length, and another continuous casting set in which the tapping request date is limited. The method according to claim 1, wherein the determination is made. 3. The method according to claim 1, further comprising, in the fourth step, moving or replacing the requested date of tapping of the continuous casting set within a predetermined range of schedule deviation. Item 2. The casting operation plan formulation method according to Item 2. 4. An operation plan for several days is created from the first day or the last day.
4. The method for formulating a casting operation plan according to claim 3.