Plate assembling method for fixed-size medium-thickness plates and blank length and design determining method

Abstract

The invention relates to the field of plate assembling design, and discloses a plate assembling method of a fixed-size medium-thickness plate and a blank length and design determining method.The plate assembling method comprises the steps that position coding is conducted on a plurality of sub-plates, the mapping relation between the coding positions and the lengths of the sub-plates is obtained, and the sections of the sub-plates are the same; sorting the coding positions of the plurality of daughter boards in an ascending order; constructing a first constraint condition according to the lengths of the plurality of daughter boards sorted according to the coding positions and the upper limit of the length of the mother board; according to the lower limit of the lengths of the mother boards, the sum of the lengths of the daughter boards in each first combination and the number of the needed mother boards, an objective function about the minimum residual material amount is constructed; and solving the objective function by adopting a meta-heuristic algorithm under a first constraint condition to obtain a minimum residual material quantity and a plate assembling mode corresponding to the minimum residual material quantity. According to the plate assembling method for the fixed-size medium-thickness plates, the order data adaptability is wider, arrangement is faster, and the stability and efficiency of plate assembling design can be effectively improved.

Description

Technical Field

[0001] The invention relates to the field of plate assembly design, and in particular to a plate assembly method for medium and thick plates of a certain size, and a method for determining the length and design of a blank. Background Art

[0002] With the refined management requirements of steel enterprises and the diversified product requirements of customers, the orders of medium and thick plates of steel enterprises are becoming more flexible, with higher requirements for small batches, steel grades and specifications. The finished products of medium and thick plates have many specifications, which requires high billet design for steelmaking. Compared with other steel products, the billet design and matching utilization are more difficult.

[0003] At present, the plate assembly method and billet design of domestic medium and thick plate mills are mostly based on manual arrangement. First, the orders to be produced are selected according to the conditions of delivery date and production matching, and the orders to be produced are grouped according to the same specifications and the same steel type. The medium and thick plate assembly and steelmaking billet design are carried out according to the goal of minimum residual material using Excel tables. This method relies on the experience of plate assembly and billet designers, which is time-consuming and labor-intensive and has low stability. At the same time, this method does not have optimality guarantee, and cannot guarantee the minimum residual material produced and the optimal corresponding billet design. Summary of the invention

[0004] The purpose of the present invention is to provide a method for assembling medium and thick plates of fixed sizes, and a method for determining the length and design of blanks. It provides a method for assembling medium and thick plates of fixed sizes with wider adaptability of order data and faster arrangement, which can effectively improve the stability and efficiency of the assembly design.

[0005] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides a method for assembling medium and thick plates of a certain size, the method comprising: position encoding a plurality of sub-plates, and obtaining a mapping relationship between the encoding positions and lengths of the plurality of sub-plates, wherein the plurality of sub-plates have the same cross-section; sorting the encoding positions of the plurality of sub-plates in ascending order to obtain the lengths of the plurality of sub-plates sorted by the encoding positions; constructing a first constraint condition based on the lengths of the plurality of sub-plates sorted by the encoding positions and the upper limit of the length of the mother plate, wherein the first constraint condition is that the sum of the lengths of the sub-plates in each first combination is less than or equal to the upper limit of the length of the mother plate, and one of any two adjacent first combinations The encoding position of the sub-board in a combination is before the encoding position of the sub-board in another combination; according to the lower limit of the motherboard length, the sum of the lengths of the sub-boards in each first combination and the number of required motherboards, an objective function about the minimum amount of residual materials is constructed, wherein the number of required motherboards is the number of first combinations; and a meta-heuristic algorithm is used to solve the objective function under a first constraint condition to obtain the minimum amount of residual materials and a panel assembly method corresponding to the minimum amount of residual materials, wherein the panel assembly method includes: a mapping relationship between the optimized encoding positions and lengths of the multiple sub-boards and a mapping relationship between each motherboard in the required motherboards and the optimized encoding position of the sub-board in the corresponding first combination.

[0006] Preferably, the panel assembly method further includes: when a first preset number of sub-panels have the same length and the first preset number is greater than a threshold, specification encoding the first preset number of sub-panels to obtain the starting position and interval corresponding to the first preset number of sub-panels; and decoding the specification-encoded first preset number of sub-panels to obtain the position of each sub-panel in the first preset number of sub-panels represented by the initial position and the interval, and the position encoding of multiple sub-panels includes: using the acquired position of each sub-panel to position encode the multiple sub-panels; and position encoding the sub-panels that have not been specification-encoded.

[0007] Preferably, the first constraint condition is constructed by: according to the length of the i-th sub-board in the j-th first combination sorted by the coding position And the upper limit of the motherboard length l ub , construct the following first constraint:

[0008]

[0009] Among them, n j is the number of sub-boards in the jth first combination, m is the number of the first combination, is the length margin of the motherboard;

[0010] The objective function of minimizing the amount of excess material is constructed by:lb , the sum of the lengths of the sub-boards in the jth first combination And the number of motherboards m required, construct the following objective function about the minimum amount of residual material:

[0011]

[0012] Preferably, after the encoding positions of the plurality of sub-boards are sorted in ascending order, the panel assembly method further comprises: in the case where there is a stock mother board with the same cross-section as the plurality of sub-boards, constructing a second constraint condition according to the lengths of the sub-boards in a second preset number of second combinations of the plurality of sub-boards sorted by encoding position and the length of each stock mother board in the second preset number of stock mother boards, wherein the second constraint condition is that the sum of the lengths of the sub-boards in each second combination is less than or equal to the length of the corresponding stock mother board, and the encoding position of the sub-board in one of any two adjacent second combinations is before the encoding position of the sub-board in the other combination; constructing a first constraint condition according to the lengths of the other sub-boards sorted by encoding position and the upper limit of the mother board length, wherein the first constraint condition is that the sum of the lengths of the sub-boards in each first combination is less than or equal to the upper limit of the mother board length, the encoding position of the sub-board in one of any two adjacent first combinations is before the encoding position of the sub-board in the other combination, and the encoding position of the sub-board in the second combination is before the encoding position of the sub-board in the first combination; according to each first combination The third constraint condition is constructed based on the number of sub-boards in the motherboard and the number of the first combination, and the number of sub-boards in each second combination and the number of the second combination, wherein the third constraint condition is a condition on the total number of sub-boards; the objective function on the minimum amount of residual material is constructed based on the lower limit of the motherboard length, the sum of the lengths of the sub-boards in each first combination, the number of required motherboards, the length of each stock motherboard, and the sum of the lengths of the sub-boards in each second combination and the second preset number, wherein the number of required motherboards is the number of the first combination, and the number of required stock motherboards is the number of the second combination; and the objective function is solved by using a meta-heuristic algorithm under the first constraint condition, the second constraint condition, and the third constraint condition to obtain the minimum amount of residual material and a panel assembly method corresponding to the minimum amount of residual material, wherein the panel assembly method includes: the number of required motherboards, the mapping relationship between the optimized encoding positions and lengths of the plurality of sub-boards, the mapping relationship between each motherboard in the required motherboards and the optimized position of the corresponding sub-board in the first combination, and the mapping relationship between each motherboard in the required stock motherboards and the optimized position of the corresponding sub-board in the second combination.

[0013] Preferably, the constructing the second constraint condition comprises:

[0014] According to the length of the i-th sub-board in the j-th second combination of the plurality of sub-boards sorted by the encoding position and the length of the jth stock motherboard Construct the following second constraint:

[0015]

[0016] in, is the number of sub-boards in the j-th second combination, p is the second preset number, is the length margin of the motherboard;

[0017] The first constraint condition is constructed by: according to the length of the i-th sub-board in the j-th first combination sorted by the coding position And the upper limit of the motherboard length l j,ub , construct the following first constraint:

[0018]

[0019] Among them, n j is the number of sub-boards in the jth first combination, m is the number of the first combination, is the length margin of the motherboard;

[0020] The third constraint condition is constructed by: according to the number n of sub-boards in the jth first combination j and the number of the first combination m, and the number of the sub-boards in the jth second combination With the second combination number p, the following third constraint condition on the total number of sub-boards n is constructed:

[0021]

[0022] The objective function of minimizing the amount of excess material is constructed by: lb , the sum of the lengths of the sub-boards in the jth first combination The number of motherboards required m, the length of the jth stock motherboard The sum of the lengths of the sub-boards in the j-th second combination The second preset number p constructs an objective function for the minimum amount of residual material:

[0023]

[0024] Preferably, the meta-heuristic algorithm is any one of the following: genetic algorithm, particle swarm algorithm, ant colony algorithm, ocean predator algorithm, fireworks algorithm, or simulated annealing algorithm.

[0025] Through the above technical scheme, the present invention creatively first performs position encoding on multiple sub-plates with the same cross-section, and obtains the mapping relationship between the encoding position and the length of the multiple sub-plates; then, the encoding positions of the multiple sub-plates are sorted in ascending order to obtain the lengths of the multiple sub-plates sorted by the encoding positions; then, a first constraint condition is constructed according to the lengths of the multiple sub-plates sorted by the encoding positions and the upper limit of the mother plate length; then, an objective function about minimizing the amount of waste material is constructed according to the lower limit of the mother plate length, the sum of the lengths of the sub-plates in each first combination, and the number of required mother plates; finally, a meta-heuristic algorithm is used to solve the objective function under the first constraint condition to obtain the minimum amount of waste material and the plate assembly method corresponding to the minimum amount of waste material. Therefore, the present invention provides a set of plate assembly methods for fixed-size medium and thick plates with wider adaptability to order data and faster arrangement, which can effectively improve the stability and efficiency of plate assembly design.

[0026] A second aspect of the present invention provides a method for determining the length of a blank, the method comprising: obtaining a plate assembly method corresponding to a plurality of sub-plates according to the plate assembly method of fixed-size medium and thick plates, wherein the plurality of sub-plates are steel plates; determining the amount of residual material and the yield rate of each mother plate in the required mother plates according to the plate assembly method and the lower limit of the mother plate length; and determining the length of each mother plate according to the amount of residual material of each mother plate in the required mother plates; and determining the blank length required for the plurality of sub-plates according to the length of each mother plate.

[0027] Preferably, the determination method further comprises: determining the yield rate of the motherboard according to the panel assembly method and the lower limit of the motherboard length.

[0028] A third aspect of the present invention provides a method for determining a billet design, the method comprising: determining a plurality of sub-plate sets according to order requirements, wherein the sub-plates in each sub-plate set have the same steel type and cross-section, but the sub-plates in different sub-plate sets have different steel types or cross-sections; and for each sub-plate set, determining the billet length required for each sub-plate set according to the method for determining the billet length.

[0029] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for assembling medium and thick plates of a certain size, the method for determining the length of the blank, and the method for determining the design of the blank are implemented.

[0030] A fifth aspect of the present invention provides a computer program product, comprising a computer program, which, when executed by a processor, implements the method for assembling fixed-size medium and thick plates, the method for determining the length of the blank, and the method for determining the design of the blank.

[0031] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0033] Figure 1 It is a flow chart of a method for assembling medium and thick plates of a certain size provided by an embodiment of the present invention;

[0034] Figure 2 It is a flowchart of the construction of the fitness function and the fitness calculation of the one-dimensional panel assembly optimization algorithm provided by one embodiment of the present invention;

[0035] Figure 3 It is an overall flow chart of a one-dimensional panel assembly optimization algorithm provided by an embodiment of the present invention;

[0036] Figure 4 It is a one-dimensional panel assembly optimization algorithm encoding, decoding and calculation flow chart provided by one embodiment of the present invention;

[0037] Figure 5 is an overall flow chart of a plate assembly process of a fixed-size medium and thick plate provided by an embodiment of the present invention; and

[0038] Figure 6 The present invention is a flowchart of solving a panel assembly scheme of a certain specification using a genetic algorithm with enhanced elite retention provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0040] The present invention is aimed at the assembly process of fixed-size medium and thick plates. The assembly of fixed-size medium and thick plates (for example, with a thickness of 4.5-25.0 mm) is the assembly process of sub-plates of fixed length, wherein the sub-plates are fixed in length, that is, the length of the sub-plates is cut according to the order length requirements. The present invention fully considers the various situations of the blank design and one-dimensional assembly of the orders of medium and thick plate sub-plates of fixed length, including fixed-length assembly, sub-plate specification constraints, etc., considers the inventory of slabs, takes the continuous casting machine equipment and process rules as the blank design and assembly constraints, takes the minimum of residual material as the optimization goal, and the overall algorithm adopts a meta-heuristic target optimization algorithm with one-time encoding or two-time encoding to optimize the assembly model.

[0041] Figure 1 FIG. 1 is a flow chart of a method for assembling a plate of a fixed-size medium-thick plate according to an embodiment of the present invention. Figure 1As shown, the plate assembly method includes: step S101, position encoding a plurality of sub-plates, and obtaining a mapping relationship between the encoding position and the length of the plurality of sub-plates, wherein the steel type and the cross-section of the plurality of sub-plates are the same; step S102, sorting the encoding positions of the plurality of sub-plates in ascending order to obtain the lengths of the plurality of sub-plates sorted by the encoding positions; step S103, constructing a first constraint condition according to the lengths of the plurality of sub-plates sorted by the encoding positions and the upper limit of the mother plate length, wherein the first constraint condition is that the sum of the lengths of the sub-plates in each first combination is less than or equal to the upper limit of the mother plate length, and the encoding of the sub-plates in one of any two adjacent first combinations is less than or equal to the upper limit of the mother plate length. The position is before the encoding position of the sub-board in another combination; step S104, constructing an objective function about minimizing the amount of residual material according to the lower limit of the motherboard length, the sum of the lengths of the sub-boards in each first combination and the number of required motherboards, wherein the number of required motherboards is the number of first combinations; and step S105, using a meta-heuristic algorithm to solve the objective function under the first constraint condition to obtain the minimum amount of residual material and a panel assembly method corresponding to the minimum amount of residual material, wherein the panel assembly method includes: a mapping relationship between the optimized encoding positions and lengths of the multiple sub-boards and a mapping relationship between each motherboard in the required motherboards and the optimized encoding position of the sub-board in the corresponding first combination.

[0042] The following explains and illustrates each of the above steps.

[0043] Step S101 , position encoding is performed on a plurality of sub-boards, and a mapping relationship between the encoding positions and lengths of the plurality of sub-boards is obtained.

[0044] The sections of the plurality of sub-plates are the same. The sub-plates are made of plastic plates, steel plates, etc.

[0045] In one embodiment, the plurality of sub-plates are steel plates, and the steel type and cross-section of the plurality of sub-plates are the same.

[0046] For example, for a cut-length medium and thick plate order, after order screening, the sub-plate set to be assembled is I. First, the sub-plates of each order are screened and combined. Sub-plates with the same steel grade and the same section (same thickness requirement, same width requirement) are put into the same subset, totaling n I For different subsets, the board grouping process is independent of each other. Then, for the same subset I k In various embodiments of the present invention, the process of assembling the plate of the fixed-size medium-thick plate can be introduced by taking the multiple sub-plates in any subset as an example, and the execution process between different subsets is the same.

[0047] Perform position coding on multiple sub-boards. After coding is completed, the overall position coding is obtained:

[0048] [x1,x2,…,x n ],

[0049] Map it with the sub-board length according to the coding relationship to obtain an n-dimensional relationship matrix:

[0050]

[0051] Step S102: sorting the encoding positions of the plurality of sub-boards in ascending order to obtain the lengths of the plurality of sub-boards sorted by encoding positions.

[0052] Press x i Sorting in ascending order, matrix A is converted to:

[0053]

[0054] in Satisfaction for

[0055] Step S103: construct a first constraint condition according to the lengths of the plurality of sub-boards sorted by encoding positions and the upper limit of the length of the motherboard.

[0056] Among them, the first constraint condition is that the sum of the lengths of the sub-boards in each first combination is less than or equal to the upper limit of the motherboard length, and the encoding position of the sub-board in one of any two adjacent first combinations is before the encoding position of the sub-board in the other combination.

[0057] For the first constraint, each first combination corresponds to a motherboard, and the sum of the lengths of the sub-boards corresponding to each first combination cannot exceed the upper limit of the motherboard length. In addition, the plurality of sub-boards sorted by coding position can be divided into a plurality of adjacent first combinations in sequence according to the position sorting, for example, The daughter board at is divided into combination 1, which corresponds to motherboard 1; The daughter board at is divided into group 2, which corresponds to mother board 2, and so on.

[0058] Step S104, constructing an objective function for minimizing the amount of excess material according to the lower limit of the motherboard length, the sum of the lengths of the sub-boards in each first combination, and the number of motherboards required, wherein the number of motherboards required is the number of the first combination.

[0059] For steps S103-S104, in the first embodiment, the situation where there is no motherboard in stock is considered. The first constraint condition is constructed by: according to the length of the i-th sub-board in the j-th first combination sorted by the coding position And the upper limit of the motherboard length l ub , construct the following first constraint:

[0060]

[0061] Among them, n j is the number of sub-boards in the jth first combination, m is the number of the first combination, The length margin of the motherboard.

[0062] Accordingly, the objective function of minimizing the amount of residual material is constructed as follows: according to the lower limit of the motherboard length l lb , the sum of the lengths of the sub-boards in the jth first combination And the number of motherboards m required, construct the following objective function about the minimum amount of residual material:

[0063]

[0064] Among them, ∈(x) represents the ReLU function, that is

[0065] The upper and lower limits of the motherboard length can be determined through the constraint relationship, and the process is as follows:

[0066] According to the limitations of continuous casting machines, production equipment, etc., the lower limit of billet production length is l B lb , the upper limit of length is l B ub , then the lower limit of the length of the motherboard of the kth group of sections is:

[0067]

[0068] Then the upper limit of the length of the motherboard of the kth group of sections is:

[0069]

[0070] where h k,B represents the slab thickness of the blank corresponding to the k-th group of section sub-slabs, w k,B represents the slab width of the blank corresponding to the k-th group of section sub-slabs, l k,B h represents the slab length of the blank corresponding to the k-th group of section sub-slab design, k,S Indicates the thickness of the motherboard corresponding to the k-group cross-section daughter board, w k,S Indicates the width of the motherboard corresponding to the k-group cross-section daughter board, l k,S Indicates the length of the motherboard corresponding to the k-group cross-section daughter board. Indicates the slab cutting gap value, Indicates the thickness margin of the motherboard corresponding to the daughterboard of group k section, Indicates the width margin of the motherboard corresponding to the k-group cross-section daughter board. Indicates the motherboard length margin (the motherboard length margin is generally independent of the cross section). They represent the lower limits of thickness tolerance and width tolerance of the order corresponding to the k-th group of section sub-plates, respectively. B lb , l B ub Indicates the lower and upper limits of slab production length.

[0071] Of course, since each embodiment of the present invention is described by taking only the sub-boards in the kth subset (ie, the kth group of cross-section sub-boards) as an example, the l in the present invention is lb k , l ub k 、h k,B 、w k,B , l k,B 、h k,S 、w k,S , l k,S , etc. lb , l ub 、h B 、w B , l B 、h S 、w S , l S , etc. have the same meaning.

[0072] Through the above process, the algorithm fitness function (i.e., objective function) and constraints can be determined as follows:

[0073]

[0074] Step S105, using a meta-heuristic algorithm to solve the objective function under the first constraint condition to obtain a minimum amount of residual material and a panel assembly method corresponding to the minimum amount of residual material.

[0075] The board assembly method includes: a mapping relationship between the optimized coding positions and lengths of the plurality of sub-boards and a mapping relationship between each motherboard in the required motherboards and the optimized coding positions of the sub-boards in the corresponding first combination.

[0076] The meta-heuristic algorithm is any one of the following: genetic algorithm, particle swarm algorithm, ant colony algorithm, ocean predator algorithm, fireworks algorithm, or simulated annealing algorithm.

[0077] Since this problem is an NP-hard problem and cannot be solved by analytical algorithms, the MetaHeuristic Algorithm combines the random algorithm with the local search algorithm to balance the local optimal solution and the global optimal solution, thereby effectively solving the combinatorial optimization problem. The specific solution process can be found in Figure 2 shown.

[0078] For steps S103-S104, in the second embodiment, the situation where there is a stock motherboard is considered. The stock motherboard needs to be used first, and the length of the motherboard produced in stock is determined. When the board is assembled during the calculation process, the length constraint is that the sum of the lengths of the corresponding sub-plates of the motherboard should be less than or equal to the length of the motherboard. Unlike the non-stock steel billet to be designed for billet, the non-stock steel billet to be designed for billet can be subject to a certain length control range for the steel billet according to the continuous casting process constraints, and the corresponding motherboard also has a certain length control range. Therefore, when assembling sub-plates, for the mother plate rolled from the inventory steel billet, the assembly will be carried out with the goal of minimizing the residual material and the constraint that the total length of the sub-plates does not exceed the length of the mother plate; for the mother plate of the non-inventory steel billet to be designed as the billet, the sub-plates will be combined as much as possible to have a total length within the controllable length range of the mother plate according to the actual situation, so as to minimize the residual material. For the sub-plate combination that cannot be formed into a length within the controllable length range of the mother plate, the assembly calculation will be carried out with the goal of minimizing the difference between the lower limit of the mother plate length and the total length of the sub-plates and the constraint that the total length of the sub-plates does not exceed the upper limit of the mother plate length.

[0079] After the encoding positions of the plurality of sub-boards are sorted in ascending order (i.e., step S102), the panel assembly method further includes: in the case where there is a stock mother board with the same cross-section as the plurality of sub-boards, constructing a second constraint condition according to the lengths of the sub-boards in a second preset number of second combinations of the plurality of sub-boards sorted by encoding position and the length of each stock mother board in the second preset number of stock mother boards, wherein the second constraint condition is that the sum of the lengths of the sub-boards in each second combination is less than or equal to the length of the corresponding stock mother board, and the encoding position of the sub-board in one of any two adjacent second combinations is before the encoding position of the sub-board in the other combination; constructing a first constraint condition according to the lengths of the other sub-boards sorted by encoding position and the upper limit of the mother board length, wherein the first constraint condition is that the sum of the lengths of the sub-boards in each first combination is less than or equal to the upper limit of the mother board length, the encoding position of the sub-board in one of any two adjacent first combinations is before the encoding position of the sub-board in the other combination, and the encoding position of the sub-board in the second combination is before the encoding position of the sub-board in the first combination; The number of sub-boards in a combination and the number of the first combination, and the number of sub-boards in each second combination and the number of the second combination, are used to construct a third constraint condition, wherein the third constraint condition is a condition on the total number of sub-boards; an objective function on the minimum amount of residual material is constructed according to the lower limit of the motherboard length, the sum of the lengths of the sub-boards in each first combination, the number of required motherboards, the length of each stock motherboard, and the sum of the lengths of the sub-boards in each second combination, which is the second preset number, wherein the number of required motherboards is the number of the first combination, and the number of required stock motherboards is the number of the second combination; and a meta-heuristic algorithm is used to solve the objective function under the first constraint condition, the second constraint condition, and the third constraint condition to obtain the minimum amount of residual material and a panel assembly method corresponding to the minimum amount of residual material, wherein the panel assembly method includes: the number of required motherboards, the mapping relationship between the optimized coding positions and lengths of the plurality of sub-boards, the mapping relationship between each motherboard in the required motherboards and the optimized position of the corresponding sub-board in the first combination, and the mapping relationship between each motherboard in the required stock motherboards and the optimized position of the corresponding sub-board in the second combination.

[0080] The second constraint condition is for the stock motherboard, which is similar to the first constraint condition for the non-stock motherboard. Each second combination corresponds to a stock motherboard, and the sum of the lengths of the sub-boards corresponding to each second combination cannot exceed the upper limit of the stock motherboard length. In addition, the plurality of sub-boards sorted by coding position can be divided into a plurality of adjacent first combinations in sequence according to the position sorting, for example, The sub-board at is divided into combination 1, which corresponds to the stock motherboard 1; The daughter board at is divided into combination 2, which corresponds to the stock mother board 2, and so on.

[0081] Specifically, the second constraint condition is constructed by: according to the length of the i-th sub-board in the j-th second combination of the plurality of sub-boards sorted by the coding position and the length of the jth stock motherboard Construct the following second constraint:

[0082]

[0083] in, is the number of sub-boards in the j-th second combination, p is the second preset number, The length margin of the motherboard.

[0084] If the stock motherboard is not enough to cut multiple sub-boards in the kth subset, non-stock motherboards need to be used. For example, if the number of stock motherboards that meet the steel type and section (i.e., their steel type and section are the same as those of the sub-boards) is p, the number of sub-boards corresponding to the jth stock motherboard is From the The daughter boards after the first daughter board are cut from non-stock mother boards. The daughter boards after the first daughter board are then divided into different combinations in sequence according to the coding position, and each combination corresponds to a non-stock mother board.

[0085] Specifically, the first constraint condition is constructed by: according to the length of the i-th sub-board in the j-th first combination sorted by the coding position And the upper limit of the motherboard length l ub , construct the following first constraint:

[0086]

[0087] Among them, n j is the number of sub-boards in the jth first combination, m is the number of the first combination, is the length margin of the motherboard;

[0088] The third constraint condition is constructed as follows: according to the number n of sub-boards in the jth first combination j and the number of the first combination m, and the number of the sub-boards in the jth second combination With the second combination number p, the following third constraint condition on the total number of sub-boards n is constructed:

[0089]

[0090] Accordingly, the objective function of minimizing the amount of residual material is constructed as follows: according to the lower limit of the motherboard length l lb , the sum of the lengths of the sub-boards in the jth first combination The number of motherboards required m, the length of the jth stock motherboard The sum of the lengths of the sub-boards in the j-th second combination The second preset number p constructs an objective function for the minimum amount of residual material:

[0091]

[0092] Through the above process, the algorithm fitness function (i.e., objective function) and constraints can be determined as follows:

[0093]

[0094] When the above equation is obtained, the meta-heuristic algorithm is used to solve it.

[0095] Before executing step S101, specification encoding may be performed on some sub-boards. The combination of a large number of specification encoding methods with the same specifications and a position encoding method greatly reduces the dimension of input variables and greatly improves the algorithm convergence speed and optimization effect.

[0096] The panel assembly method also includes: when the lengths of a first preset number of sub-panels are the same and the first preset number is greater than a threshold, specification encoding the first preset number of sub-panels to obtain the starting positions and intervals corresponding to the first preset number of sub-panels; and decoding the first preset number of sub-panels that have been specification-encoded to obtain the position of each sub-panel in the first preset number of sub-panels represented by the initial position and the interval.

[0097] Correspondingly, the position coding of the plurality of sub-boards includes: using the acquired position of each sub-board to position code the plurality of sub-boards; and position coding the sub-boards that have not been specification-coded.

[0098] Specifically, Figure 3 As shown, for the subset I filtered by specification k The multiple sub-boards in the same length are grouped together, and the group with the required number of sub-boards (i.e. the group with a larger number) is coded. The coded method uses two parameters λ and ξ, where λ represents the interval and ξ represents the starting position. The i-th group to be coded is [λ i ,ξ i ].

[0099] After specification coding, the daughterboard subset I kThe sub-board sets are divided into the sub-board sets without specification coding (i.e., the smaller group) and the sub-board sets with specification coding (i.e., the larger group). Corresponding sub-board quantity A collection of sub-boards for specification coding The number of groups it contains (i.e. the number of sub-board specifications) is The i-th group contains the number of sub-boards

[0100] For daughter boards that are not coded Position coding is performed, and the coding method maps the length of the sub-board to the order according to the sub-board position order; the specification coding is performed according to the specification, such as the i-th group that has been encoded is [λ i ,ξ i ], the number of daughter boards in this group is Then the corresponding position code of the j-th sub-board in this group is λ i *j+ξ i .

[0101] like Figure 4 As shown, the meta-heuristic algorithm is used to calculate dimensional vector as input to the algorithm:

[0102]

[0103] First, encode the input and then decode it. The corresponding specification decoding result is:

[0104]

[0105] satisfy The total number of positional encodings decoded is:

[0106]

[0107] Positionally encode the section:

[0108] x i =x p

[0109] To position-code all daughterboards that are not size-coded:

[0110]

[0111] satisfy

[0112] where x N iIndicates the location of a daughterboard that is not size-coded.

[0113] After the encoding is completed, the overall position encoding is obtained:

[0114] [x1,x2,…,x n ]

[0115] Where n is the total number of thick plate sub-plates of this specification, satisfying:

[0116]

[0117] in etc. can be abbreviated as m D , n N wait.

[0118] Map it with the sub-board length according to the coding relationship to obtain an n-dimensional relationship matrix:

[0119]

[0120] Press x i Sorting in ascending order, matrix A is converted to:

[0121]

[0122] in Satisfaction for

[0123] After position encoding, such as Figure 4 As shown, a matrix A about the mapping relationship between position and length is obtained, the sub-boards are sorted in ascending order of position (ie, A is orthogonally transformed), and then the fitness is determined and corresponding calculations are performed in the above manner.

[0124] To summarize, the present invention creatively first performs position encoding on multiple sub-plates with the same cross-section, and obtains the mapping relationship between the encoding position and the length of the multiple sub-plates; then, the encoding positions of the multiple sub-plates are sorted in ascending order to obtain the lengths of the multiple sub-plates sorted by the encoding positions; then, a first constraint condition is constructed according to the lengths of the multiple sub-plates sorted by the encoding positions and the upper limit of the mother plate length; then, an objective function about minimizing the amount of waste material is constructed according to the lower limit of the mother plate length, the sum of the lengths of the sub-plates in each first combination, and the number of required mother plates; finally, a meta-heuristic algorithm is used to solve the objective function under the first constraint condition to obtain the minimum amount of waste material and the plate assembly method corresponding to the minimum amount of waste material. Therefore, the present invention provides a set of plate assembly methods for fixed-size medium and thick plates with wider adaptability to order data and faster arrangement, which can effectively improve the stability and efficiency of plate assembly design.

[0125] An embodiment of the present invention provides a method for determining the length of a blank, the determination method comprising: obtaining a plate assembly method corresponding to a plurality of sub-plates according to the plate assembly method of fixed-size medium and thick plates, wherein the plurality of sub-plates are steel plates; determining the amount of residual material of each mother plate in the required mother plates according to the plate assembly method and the lower limit of the mother plate length; and determining the length of each mother plate according to the amount of residual material of each mother plate in the required mother plates; and determining the blank length required for the plurality of sub-plates according to the length of each mother plate.

[0126] The board assembly method includes: a mapping relationship between the optimized coding positions and lengths of the plurality of sub-boards and a mapping relationship between each motherboard in the required motherboards and the optimized coding positions of the sub-boards in the corresponding first combination.

[0127] In one embodiment, the determination method further comprises: determining the yield rate of the motherboard according to the board assembly method and the lower limit of the motherboard length.

[0128] Specifically, after the sub-board assembly is completed by the meta-heuristic algorithm, if the stock motherboard is not considered, the remaining material amount Δl of the motherboard can be determined by the following formula:

[0129]

[0130] For the case of considering the stock motherboard, the remaining material volume Δl of the motherboard can be determined by the following formula:

[0131]

[0132] The term in brackets in the above summation formula is the remaining material of the j-th motherboard.

[0133] First, when the amount of excess material is determined to be the smallest, the length of each motherboard can be determined according to the amount of excess material of each motherboard, and then the length l of the motherboard required for multiple daughter boards can be calculated. S (It can also be expressed as l k,S ).

[0134] Then, according to the following relationship between the steelmaking slab and the mother plate, the corresponding billet length can be determined as:

[0135]

[0136] where h k,B represents the slab thickness of the blank corresponding to the k-th group of section sub-slabs, w k,B represents the slab width of the blank corresponding to the k-th group of section sub-slabs, l k,B h represents the slab length of the blank corresponding to the k-th group of section sub-slab design, k,S Indicates the thickness of the motherboard corresponding to the k-group cross-section daughter board, w k,S Indicates the width of the motherboard corresponding to the k-group cross-section daughter board, lk,S Indicates the length of the motherboard corresponding to the k-group cross-section daughter board. Indicates the slab cutting gap value, Indicates the thickness margin of the motherboard corresponding to the daughterboard of group k section, Indicates the width margin of the motherboard corresponding to the k-group cross-section daughter board. Indicates the motherboard length margin (the motherboard length margin is generally independent of the cross section). Indicates the lower limit of the thickness tolerance of the order corresponding to the k-th group of section sub-plates (which is generally less than or equal to 0), is the length of the jth stock motherboard. Other parameters can be found in the above description.

[0137] The motherboard design and blank design are carried out according to the one-dimensional panel optimization results. Specifically, after the sub-panel panel is assembled by the meta-heuristic algorithm, the corresponding relationship between each group of sub-panels and the corresponding motherboard can be determined. In other words, and

[0138] Yield rate:

[0139]

[0140] Because production must at least be carried out according to the lower limit of the motherboard, if the length of the assembled board is greater than or equal to the lower limit of the motherboard length, it is calculated according to the length of the assembled board. If it is less than the lower limit of the motherboard length, it is calculated according to the lower limit of the motherboard length. Therefore, max() is used in the first term of the denominator of the above formula.

[0141] Wherein, n is the number of the plurality of sub-boards, and n satisfies the following formula:

[0142]

[0143] This method can be used to complete all motherboard designs and blank designs corresponding to the order.

[0144] Application and implementation in steel plant medium and thick plate plant, such as Figure 5 As shown, the specific steps are as follows:

[0145] Establish a one-dimensional plate assembly and billet design optimization system based on medium and thick plates. 1. Connect to the ERP system or production and sales system to obtain medium and thick plate order information; 2. Screen and combine the sub-plates of each order, and the sub-plates with the same steel grade and section are placed in the same group; 3. Connect to the MES system to obtain the inventory information of stored steel and select the stored steel plate billets to be used; 4. Arrange the plate assembly: calculate the billet length constraints for the sub-plate groups, calculate the mother plate length constraints based on the billet length constraints, and then encode the specifications of the group of sub-plates, encode the positions of the sub-plates with specification encoding, and then optimize the sub-plate assembly through the meta-heuristic algorithm. The optimization results are verified by secondary calculation to obtain the final optimization results of the group, and then the optimization results are decoded by position and specification to obtain the plate assembly results; 5. Traverse step 4 to calculate all group assembly results; 5. Perform mother plate design and yield rate calculation; 6. Perform billet design.

[0146] In a feasible specific implementation, the meta-heuristic algorithm adopts a genetic algorithm with enhanced elite retention. According to the rapidity and applicability of the algorithm, the algorithm adopts a variable coefficient particle swarm with a compression factor and a genetic algorithm with enhanced elite retention.

[0147] like Figure 6 As shown, the enhanced elite-preserving genetic algorithm is used for calculation. The enhanced elite-preserving genetic algorithm includes encoding, decoding, initial population generation, fitness calculation, selection, crossover, and mutation. This algorithm uses a real-valued coded population, that is, an encoding method that does not require decoding, and uses the elite selection method to select individuals in the population, selecting a small number of optimal candidate solutions and retaining them to the next generation, ensuring that GA avoids repeated calculations of some inferior solutions, thereby accelerating the convergence of the algorithm.

[0148] The program code of the method of the present embodiment can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code can be executed entirely on the machine, partially on the machine, partially on the machine as an independent software package and partially on a remote machine or completely on a remote machine or server. This application case uses Python to write the core algorithm and process processing program.

[0149] The present invention fully considers various situations of the blank design and one-dimensional assembly of the orders of medium and thick plate fixed-length sub-plates, including fixed-length assembly, sub-plate specification constraints, etc., considers the inventory of slabs, takes the continuous casting machine equipment and process rules as the blank design and assembly constraints, takes the minimum surplus material as the optimization goal, and the overall algorithm adopts the meta-heuristic target optimization algorithm of secondary encoding and decoding to optimize the assembly model. The core solution of the problem is solved by the meta-heuristic algorithm, and the encoding and decoding of the sub-plate specifications with a large number of the same specifications greatly improves the efficiency and accuracy of the algorithm.

[0150] The present invention belongs to a method for optimizing the design of one-dimensional assembly and billet of medium and thick plates, and solves the optimal assembly method with a multivariate heuristic algorithm, effectively reduces waste materials, improves the yield rate, intuitively reduces costs, and improves the economic benefits of steel plants; the calculation speed and stability of the algorithm are effectively improved through two codings, and the algorithm is implemented in a computer software system to help steel plants make decisions and provide guidance on the one-dimensional assembly and billet design of fixed-length medium and thick plates.

[0151] An embodiment of the present invention provides a method for determining a billet design, the method comprising: determining a plurality of sub-plate sets according to order requirements, wherein the sub-plates in each sub-plate set have the same steel type and cross-section, but the sub-plates in different sub-plate sets have different steel types or cross-sections; and for each sub-plate set, determining the billet length required for each sub-plate set according to the method for determining the billet length.

[0152] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the method for assembling fixed-size medium and thick plates, the method for determining the length of the blank, and the method for determining the blank design are implemented.

[0153] An embodiment of the present invention provides a computer program product, including a computer program, which, when executed by a processor, implements the method for assembling thick and medium plates of a certain size, the method for determining the length of a blank, and the method for determining the design of a blank.

[0154] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0155] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0156] Those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including a number of instructions to enable a single-chip microcomputer, a chip or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0157] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0158] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0159] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for assembling medium and thick plates of a certain size, characterized in that: The panel assembly method comprises: Position encoding is performed on a plurality of sub-plates, and a mapping relationship between the encoding positions and the lengths of the plurality of sub-plates is obtained, wherein the plurality of sub-plates have the same cross-section; sorting the encoding positions of the plurality of sub-boards in ascending order to obtain the lengths of the plurality of sub-boards sorted by the encoding positions; Constructing a first constraint condition according to the lengths of the plurality of sub-boards sorted by coding positions and the upper limit of the length of the motherboard, wherein the first constraint condition is that the sum of the lengths of the sub-boards in each first combination is less than or equal to the upper limit of the length of the motherboard, and the coding position of the sub-board in one of any two adjacent first combinations is before the coding position of the sub-board in the other combination; Constructing an objective function for minimizing the amount of excess material according to the lower limit of the motherboard length, the sum of the lengths of the sub-boards in each first combination, and the number of motherboards required, wherein the number of motherboards required is the number of the first combination; and A meta-heuristic algorithm is used to solve the objective function under the first constraint condition to obtain the minimum amount of residual materials and a panel assembly method corresponding to the minimum amount of residual materials, wherein the panel assembly method includes: a mapping relationship between the optimized coding positions and lengths of the multiple sub-boards and a mapping relationship between each motherboard in the required motherboards and the optimized coding positions of the sub-boards in the corresponding first combination.

2. The panel assembly method according to claim 1, characterized in that: The panel assembly method further comprises: When the lengths of the first preset number of sub-boards are the same and the first preset number is greater than a threshold, performing specification encoding on the first preset number of sub-boards to obtain starting positions and intervals corresponding to the first preset number of sub-boards; and Decoding the first preset number of sub-boards encoded by the specification to obtain the position of each sub-board in the first preset number of sub-boards represented by the initial position and the interval, The position encoding of the plurality of sub-boards comprises: The acquired position of each sub-board is used to perform position coding on the plurality of sub-boards; and the sub-boards that are not size-coded are position-coded.

3. The panel assembly method according to claim 1 or 2, characterized in that: The constructing of the first constraint condition comprises: According to the length of the i-th sub-board in the j-th first combination sorted by encoding position And the upper limit of the motherboard length l ub , construct the following first constraint: Among them, n j is the number of sub-boards in the jth first combination, m is the number of the first combination, is the length margin of the motherboard; The objective function of constructing the minimum amount of residual material includes: According to the lower limit of motherboard length l lb , the sum of the lengths of the sub-boards in the jth first combination And the number of motherboards m required, construct the following objective function about the minimum amount of residual material:

4. The panel assembly method according to claim 1 or 2, characterized in that: After sorting the encoding positions of the plurality of sub-boards in ascending order, the board assembly method further includes: In the case where there is a stock motherboard having the same cross section as the plurality of daughter boards, a second constraint condition is constructed according to the lengths of the daughter boards in a second preset number of second combinations of the plurality of daughter boards sorted by coding position and the length of each of the second preset number of stock mother boards, wherein the second constraint condition is that the sum of the lengths of the daughter boards in each second combination is less than or equal to the length of the corresponding stock mother board, and the coding position of the daughter boards in one combination of any two adjacent second combinations is before the coding position of the daughter boards in the other combination; According to the lengths of the other sub-boards sorted by coding positions and the upper limit of the motherboard length, a first constraint condition is constructed, wherein the first constraint condition is that the sum of the lengths of the sub-boards in each first combination is less than or equal to the upper limit of the motherboard length, the coding position of the sub-board in one of any two adjacent first combinations is before the coding position of the sub-board in the other combination, and the coding position of the sub-board in the second combination is before the coding position of the sub-board in the first combination; Constructing a third constraint condition according to the number of sub-boards in each first combination and the number of the first combination, and the number of sub-boards in each second combination and the number of the second combination, wherein the third constraint condition is a condition on the total number of sub-boards; According to the lower limit of the motherboard length, the sum of the lengths of the sub-boards in each of the first combinations, the number of required motherboards, the length of each of the motherboards in stock, and the sum of the lengths of the sub-boards in each of the second combinations, the second preset number, constructing an objective function for the minimum amount of excess material, wherein the number of motherboards required is the number of the first combination, and the number of motherboards required in stock is the number of the second combination; and A meta-heuristic algorithm is used to solve the objective function under the first constraint, the second constraint and the third constraint to obtain the minimum amount of residual materials and a panel assembly method corresponding to the minimum amount of residual materials, wherein the panel assembly method includes: the number of required mother boards, the mapping relationship between the optimized coding positions and lengths of the multiple sub-boards, the mapping relationship between each mother board in the required mother boards and the optimized positions of the sub-boards in the corresponding first combination, and the mapping relationship between each mother board in the required inventory mother boards and the optimized positions of the sub-boards in the corresponding second combination.

5. The panel assembly method according to claim 4, characterized in that: The constructing of the second constraint condition comprises: According to the length of the i-th sub-board in the j-th second combination of the plurality of sub-boards sorted by the encoding position and the length of the jth stock motherboard Construct the following second constraint: in, is the number of sub-boards in the j-th second combination, p is the second preset number, is the length margin of the motherboard; The constructing of the first constraint condition comprises: According to the length of the i-th sub-board in the j-th first combination sorted by encoding position And the upper limit of the motherboard length l ub , construct the following first constraint: Among them, n j is the number of sub-boards in the jth first combination, m is the number of the first combination, is the length margin of the motherboard; The constructing of the third constraint condition comprises: According to the number n of sub-boards in the jth first combination j and the number of the first combination m, and the number of the sub-boards in the jth second combination With the second combination number p, the following third constraint condition on the total number of sub-boards n is constructed: The objective function of constructing the minimum amount of residual material includes: According to the lower limit of motherboard length l lb , the sum of the lengths of the sub-boards in the jth first combination The number of motherboards required, m, and the length of the jth stock motherboard The sum of the lengths of the sub-boards in the j-th second combination The second preset number p constructs an objective function for the minimum amount of residual material:

6. The panel assembly method according to claim 1, characterized in that: The meta-heuristic algorithm is any one of the following: genetic algorithm, particle swarm algorithm, ant colony algorithm, ocean predator algorithm, fireworks algorithm, or simulated annealing algorithm.

7. The determination method according to any one of claims 1 to 6, characterized in that: The plurality of sub-plates are steel plates, and the steel type and cross-section of the plurality of sub-plates are the same.

8. A method for determining the length of a blank, characterized in that: The determination method comprises: According to the plate assembly method of fixed-size medium and thick plates according to any one of claims 1 to 7, a plate assembly method corresponding to a plurality of sub-plates is obtained, wherein the plurality of sub-plates are steel plates; Determine the amount of excess material of each motherboard in the required motherboards according to the panel assembly method and the lower limit of the motherboard length; Determining the length of each motherboard according to the remaining material amount of each motherboard in the required motherboards; and The blank lengths required for the plurality of daughter boards are determined according to the length of each mother board.

9. The determination method according to claim 8, characterized in that: The determination method further comprises: The yield rate of the motherboard is determined according to the board assembly method and the lower limit of the motherboard length.

10. A method for determining a blank design, characterized in that: The determination method comprises: Determine multiple sub-plate sets according to the order requirements, wherein the sub-plates in each sub-plate set have the same steel grade and section, but the sub-plates in different sub-plate sets have different steel grades or sections; and For each sub-plate set, the blank length required for each sub-plate set is determined according to the method for determining the blank length according to claim 7 or 8.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the method for assembling medium and thick plates of a certain size as described in any one of claims 1 to 7, the method for determining the length of the blank as described in claim 8 or 9, and the method for determining the blank design as described in claim 10.

12. A computer program product, characterized in that It comprises a computer program which, when executed by a processor, implements the method for assembling medium and thick plates of a certain size as described in any one of claims 1 to 7, the method for determining the length of a blank as described in claim 8 or 9, and the method for determining the design of a blank as described in claim 10.

Images