JPH06142724A - Blank layout method - Google Patents

Abstract

PURPOSE:To provide a blank layout method which can create an optimum blank layout plan in a short time capable of enduring practical use. CONSTITUTION:When one or more orders 0 are appropriated to each of plural slabs S to create the blank layout plan, this blank layout method is so constituted that the sequence of use of the slabs S and the appropriating sequence of the order 0 to the slabs S are recombined by the simulated annealing method SA, a blank layout plan about each combination code (x) is prepared and an evalution function E1 based on a prescribed condition is applied to this blank layout plan to determine the optimum blank layout plan. The optimum blank layout plan can be created by this constitution in the short time capable of enduring practical use.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate removing method, and more particularly to a material removing method for optimally combining a plurality of orders from a plurality of slabs such as metal.

[0002]

2. Description of the Related Art Conventionally, when a planing plan is created by allocating a plurality of orders to a plurality of slabs, a person in charge of planning prepares a combination of the plurality of slabs and the order information provided. I was erroneously asking for it, and was cutting it.

[0003]

The above-described conventional planing method in which a person makes a planing plan by seeking combinations by trial and error has the following problems. (1) Since the amount of information used in the planing plan is extremely large, the number of combinations of slabs and orders becomes enormous, but the number of combinations that can be manually obtained is limited. (2) Further, there are many restrictions on the planing, and it takes time and effort to find a combination satisfying this condition from the combinations obtained above. (3) Furthermore, it is difficult to evaluate the optimality of the final planing. It is an object of the present invention to improve a planing method in order to solve the problems in the related art and to provide a planing method capable of creating an optimum planing plan in a short time that can be put to practical use. It is what

[0004]

In order to achieve the above object, the present invention relates to the order of use of the plate materials and the plate materials when a plate cutting plan is prepared by applying one or more orders to each of the plate materials. The order of appropriation to the above is rearranged by a simulated annealing method to create a planing plan for each combination, and an evaluation function based on a predetermined condition for the planing is applied to each planing plan. It is configured as a planing method by determining an optimal planing plan. The predetermined conditions include conditions such that the area of the scrap portion of the plate material is minimized, productivity, delivery date of the order, and old plate material is used as soon as possible.

[0005]

According to the present invention, when one or more orders are applied to each of a plurality of plate materials to create a planing plan, the order of using the plate materials and the order of applying the orders to the plate materials are simulated.・ Changing by the annealing method, a planing plan for each combination is created. Then, an optimum evaluation plan is determined by applying an evaluation function based on a predetermined condition to each removal plan. That is, it is possible to quickly find a combination of the order of use of the plate materials and the order of application of the order, and it is possible to easily find a combination satisfying the above conditions from this combination. Therefore, the yield and the like are improved and the combination creation time can be shortened. In addition, the final planing optimality can be objectively evaluated. As a result, it is possible to obtain a planing method that can create an optimal planing plan in a short time that can withstand actual use.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings for the understanding of the present invention. The following embodiments are examples of embodying the present invention and are not intended to limit the technical scope of the present invention. Here, FIG. 1 is a flowchart (a) showing a procedure for creating a planing plan by a planing method according to an embodiment of the present invention,
(B), FIG. 2 is a table showing the specifications of the slab and the order, and the contents of combination thereof, and FIG. 3 is a planing plan of the planing method according to the present embodiment. The board cutting problem in this embodiment means that a plurality of orders 0 for a plurality of slabs S (corresponding to a plate material)
Is an issue that is optimally applied to. Here, "optimum" means that in creating a planing plan, in addition to minimizing the area of the scrapped part of the slab S, productivity, delivery time of order 0, use of the old slab S as soon as possible, etc. Means to be satisfied. In addition, this planing problem has the following features. (1) The slab S in order 0 has the same shape (rectangle), but has attributes of length × thickness × width × steel type, and there are many types. (2) A slab S of a plurality of steel types can be applied to one order 0. (3) The size of the material is variable because the material is made by rolling the slab S instead of filling the order 0 from the material of a fixed size. (4) There is a restriction on how to arrange Order 0 within the same material (for example, an order wider than the first order cannot be placed). (5) Only order 0 of the same thickness can be taken from the same material. (6) In the inside out of (2) above, the materials that can be ordered 0 are limited by the steel grade. In such a problem, order 0 is applied to Slab S (Slab S
And the order 0) to determine the arrangement of the order 0 in the slab S, especially for problems with a large solution space for the reasons (1) to (3) above. It can be said that there is. For this reason, in this embodiment, a simulated annealing method, which is a powerful method for solving a large-scale combinatorial optimization problem, is used.
(Hereinafter abbreviated as SA) is used. That is, the optimum solution is obtained while performing a so-called transition in which the solution candidates of the problem considered for the metal to be annealed by SA are changed. When applied to actual problems, the number of slabs S is about 200 and the number of orders 0 is about 96.
It is not practical in terms of calculation time to find an optimum solution using all data at the same time, which is very large. Therefore,
In order to narrow the solution space, the data were grouped by a certain standard, and SA was applied to each group.

A procedure for creating a planing plan by the planing method according to this embodiment will be described below in the order of steps S1, S2, ... With reference to FIGS. Figure 1
As shown in (a), in this embodiment, first, each data of slab S and order 0 is input (S1) and grouped (S).
2). As the grouping method, for example, the following two methods are applied. Method of grouping Order 0 with common usable steel types Method of further grouping the items classified by the grouping by the above method The above method requires a small number of Orders 0 Although it decreases, if the search space is too narrow, the optimal solution may be missed. On the contrary, although the above method is less likely to miss the optimal solution, the calculation time is longer than that of the above method. Initial setting with group number i = 1 (S
3) After that, the group i is optimized by SA (S
4). Hereinafter, the content of step S4 will be described more specifically with reference to FIG. In SA, first, the initial temperature T0 is set (S11). The initial temperature T0 is the temperature T which is one of the parameters for performing the convergence calculation by SA.
Is an initial value of, and needs to be set to a value sufficient to cause a change, that is, a transition of a solution candidate of the problem considered in the metal to be annealed. Next, in SA, the solution candidate of the problem is represented by a code x consisting of a fixed-length character string. Here, the code x is assumed to be composed of the first half code indicating the use order of the slab S and the second half code indicating the allocation order of the order 0. For example, in FIG.
As shown in (b), the number of slabs S is 6 and the number of orders 0 is 7
In the case of, the solution candidate is expressed by the following 13-digit code. The combination of the slab S corresponding to the code x and the order 0 is as shown in FIG. Neighborhood Sx of this code x
A so-called transition candidate x ′, which is a new code, is randomly selected and generated from (a code group different from the code x in the order of use of only one slab S or the order of allocation of order 0) (S1).
2). The algorithm for creating this transition candidate x ′ is, for example, 2
The use order of one slab S or the allocation order of order 0 is randomly changed.

With respect to the order of use of the slab S represented by the code x and the transition candidate x'created in this way, and the order of allocation of order 0, the plate thickness constraint, steel type constraint, and the leading plate width are maximized. Find a combination of slab S and order 0 that satisfies the constraint. At this time, the length of the material is determined by the size of the order at the beginning, and taking this into consideration, the slab S
And the combination of order 0. Then, a planing plan as shown in Fig. 3 is created for these combinations. In FIG. 3, a maximum of two slabs is taken in the width direction, and whether or not two slabs are taken is determined by the width of order 0. The following evaluation function E1 is obtained to evaluate the optimality of such a planing plan (S13). E1 = Σ (Cai + Cbi + Ai * Cci) (1) However, E1: Sum of evaluation functions Ca: Loss amount of waste within block Cb: Loss time required for setup required for cutting Cc: Waste outside block Amount of loss A: 30 / oldness of slab (number of days elapsed after manufacturing slab S) Here, a block represents a length in which orders of the same width are successively placed, and the minimum value of the block is due to equipment restrictions. It is predetermined. FIG. 3 shows an example of Cb and the relationship between blocks, Ca, and Cc. Further, the coefficient A serves as a weight for the waste Cc outside the block, and when the areas of the waste Cc outside the block are equal, the coefficient A and the evaluation function E1 are smaller when the old slab S is used. You can see. Then, the evaluation function E1 before and after the transition that is the rearrangement of the code between the code x and the transition candidate x ′
The change Δ of is calculated (S14). Based on the change Δ of the evaluation function E1, it is determined whether to accept or reject the transition candidate x ′ (S15). That is, when the transition candidate x ′ is generated, the current state x is changed to x ′ with the probability P (Δ). This is called "accept transition candidate" or "perform transition". On the contrary, the current candidate is discarded with probability 1-P (Δ). This is called "rejecting transition candidates". Here, P (Δ) is represented by the following equation. P (Δ) = 1, ifΔ ≦ 0 (2a) P (Δ) = exp (−Δ / T), ifΔ> 0 (2b) If the transition candidate x ′ is not accepted, Sx again. Repeat randomly selecting x ′ from. A uniform random number r in the interval (0, 1) is used for the step of accepting each with probability P (Δ). That is, r is P
If it is smaller than (Δ), the transition candidate x ′ is accepted, and if it is larger, it is rejected. As can be seen from the above formula (2b), when the evaluation function E1 becomes worse (Δ>
It is a feature of SA that the transition candidate x ′ is accepted with a certain probability even in the case (0). Therefore, it is possible to escape from the minimal solution. Such transition is repeated until the equilibrium condition at the temperature T is achieved (S16). If equilibrium is achieved (until the end condition is satisfied (S17)), the temperature T is updated (S18), and steps S12 to S are performed.
Repeat 18. In this way, when the temperature T is gradually lowered and the end condition is satisfied, the evaluation function E1 is minimized and the optimum planing plan is obtained.

The initial temperature T0 setting method, the equilibrium condition judging condition at each temperature, the temperature T updating method, and the ending condition judging method in the above algorithm are, for example, Kirkpatrick, Hu.
A well-known annealing schedule such as ang is used. Optimization of group i by such SA (S4)
After the completion, the code x ″ indicating the optimum planing plan result in the group i is output together with the evaluation function E1 ″ (S
5). i = i + 1 is set (S6). Step S4 ~
S6 is repeated for all groups (S7). As described above, the optimum planing plan can be determined by transitioning the code x indicating the order of use of the slabs S and the order of application of order 0, which are considered to be the metals to be annealed for all the groups. That is, it is possible to quickly find a combination of the use order of the slab S and the allocation order of the order 0, and it is possible to easily find a combination that satisfies the condition from this combination. Therefore, the yield etc. is improved,
The combination creation time can be shortened. In addition, the final planing optimality can be objectively evaluated. As a result, it is possible to obtain a planing method capable of creating an optimal planing plan within a practical time range. In addition, in the above-described embodiment, the slab S has been applied to the plate removal, but in actual use, the slab S may be applied to the plate removal of the rolled material. The evaluation function E used in the above embodiment is
Instead of 1, evaluation functions E2, E3, E4 represented by the following expressions may be used depending on the situation. (1)
When it is necessary to consider the delivery date of order 0 E2 = (1 + NP / TNO) Σ (Cai + Cbi + Ai * Cci) (3) where NP: the number of orders (must order) whose delivery date is not manufactured (must order) ( (Must order can be set by delivery date) TNO: Total number of orders in the group (2) When it is not necessary to use the oldest slab S E3 = Σ (Cai + Cbi + Cci) (4) (3) Delivery date and yield When it is desired to adjust the balance with E4 = Σ (Cai + Cbi + Cci + NP) (5) Furthermore, the first to the first of the above formulas (1), (3), (4), and (5)
Weights Wa, Wb, Wc are added to Ca, Cb, Cc of the third term, respectively.
You may multiply by.

[0010]

EFFECTS OF THE INVENTION Since the plate removing method according to the present invention is configured as described above, it is possible to change the codes representing the order of use of slabs and the order of application of orders of slabs, which are made of metal to be annealed. The optimal planing plan can be determined. That is, it is possible to quickly find the combination of the slab use order and the order appropriation order, and it is possible to easily find a combination that satisfies the conditions from this combination. Therefore, the yield and the like are improved and the combination creation time can be shortened. In addition, the final planing optimality can be objectively evaluated. As a result, it is possible to obtain a planing method capable of creating an optimal planing plan in a short time that can be put to practical use.

[Brief description of drawings]

FIG. 1 is a flowchart (a) showing a procedure for creating a planing plan by a planing method according to an embodiment of the present invention,
(B).

FIG. 2 is a chart showing specifications of slabs and orders and the contents of combination thereof.

FIG. 3 is a plan view of a planing according to a planing method of the present embodiment.

[Explanation of symbols]

 S ... Slab (corresponding to plate material) 0 ... Order x, x ', x "... Code (or transition candidate) E1, E1', E1" ... Evaluation function SA ... Simulated annealing method

Front page continuation (72) Inventor Shigeru Sakai 1 Kanazawa-machi, Kakogawa-shi, Hyogo Kamido Steel Works, Ltd. Kakogawa Steel Works (72) Inventor Sasaki 1 Kanazawa-machi, Kakogawa-shi, Hyogo Kakogawa Steel Works, Ltd. Inside the Steel Works (72) Inventor Yoshio Tomita 1 Kanazawa Town, Kakogawa City, Hyogo Prefecture Kado Steel Works Kakogawa Works

Claims (1)

[Claims] 1. When preparing a planing plan by allocating one or more orders to each of a plurality of plate materials, the order of using the plate materials and the order of applying the order to the plate materials are simulated by a simulated annealing method. A planing method in which a planing plan for each combination is created by recombining, and an optimum planing plan is determined by applying an evaluation function based on a predetermined condition for each planing plan.