Patent ID: 9734539
Date: 2017-08-15
CPC Classifications: G06Q,Y02P

Claim:
1. A coordinated coil scheduling method of multiple production lines in a cold rolling area in a steel plant, the production lines including an acid rolling line, a continuous annealing line, a hot galvanizing line, and a hot aluminizing and galvanizing line, the method comprising: Step 1: acquiring information about candidate coils to be scheduled for each of multiple production lines in the cold rolling area; Step 2: building a coordinated coil scheduling model of multiple production lines in the cold rolling area in the steel plant; Step 2-1: according to production technological requirements of the production lines, calculating abrasion penalties and changeover penalties incurred by equipment adjustment due to different production requirements, comprising: abrasion penalties of equipment incurred by equipment adjustment due to different widths of two adjacent coils in a production line, abrasion penalties of equipment incurred by equipment adjustment due to different thicknesses of two adjacent coils in a production line, abrasion penalties of equipment incurred by equipment adjustment due to different surface requirements of two adjacent coils in a production line, abrasion penalties of equipment incurred by equipment adjustment due to different annealing temperatures of two adjacent coils in a production line, abrasion penalties of equipment incurred by equipment adjustment due to different weights of the surface plates of two coils in a production line, and abrasion penalties of equipment incurred by equipment adjustment due to different post-processing requirements of two coils in a production line; Step 2-2: among coil schedules corresponding to the production lines in a cold rolling supply chain composed by multiple production lines, an objective function of coordinated coil scheduling of multiple lines in the cold rolling area is built as minimizing the abrasion penalties and changeover penalties incurred by equipment adjustment due to different production requirements, where a decision variable of the objective function is represented as x Step 2-3: constraints comprise ones for each of the multiple lines and cohesion constraints among the production lines; where the constraints for each of the multiple lines include: (1) for each of all actual coils, there must be exactly one coil being processed immediately before it; (2) for each of all the actual coils, there must be exactly one coil being processed immediately after it; (3) changeover in width, thickness, surface requirement, and annealing temperature of lines should not exceed predetermined upper limits; (4) it should be guaranteed that determination to a processing time of coils in each line will not incur idle time between any two adjacent processed coils; (5) for each of the coils, it should be processed exactly once in a production line along its required processing path; where the cohesion constraints among the production lines imply a cohesion relationship between the production lines that the coil cannot be processed in a downstream production line until it is finished in an upstream production line; Step 3: an initial coordinated coil schedule of multiple production lines in the cold rolling area is obtained by using an heuristic algorithm, which includes an initial coil schedule in acid rolling line, an initial coil schedule in continuous annealing line, an initial coil schedule in hot galvanizing line, and an initial schedule of coils in hot aluminizing and galvanizing line; Step 3-1: Determine the initial coil schedule in acid rolling line: an initial coil schedule in the acid rolling line is obtained by sequencing the coils to be processed in a descending order of a surface requirement code, and then sequencing the coils with a same surface requirement in a descending order of their widths, and then sequencing the coils with the same surface requirement and a same width in a descending order of their post-processing codes, and then sequencing the coils with the same surface requirement and the same width and a same post-processing code in an descending order of their annealing temperatures; Step 3-2: calculating a starting time and a finishing time of each coil in the initial coil schedule in the acid rolling line; Step 3-3: determine an initial coil schedule in a continuous annealing line: an initial annealing schedule of coils in a material inventory of continuous annealing line is obtained by sequencing the coils to be annealed in a descending order of their widths, and then sequencing the coils with the same width in a descending order of their annealing temperatures, and then sequencing the coils with the same width and a same annealing temperature in a descending order of their thicknesses, a coil schedule in continuous annealing line is obtained by selecting the coils to be annealed from the coil schedule in the acid rolling line, and sequentially inserting them after the initial annealing schedule of coils in the material inventory of continuous annealing line; Step 3-4: determine an initial coil schedule in the hot galvanizing line: an initial schedule of the coils in the material inventory of hot galvanizing line is obtained, by sequencing the coils in the material inventory of hot galvanizing line in a descending order of their post-processing codes; and then sequencing the coils with the same post-processing code in a descending order of their widths; and then sequencing the coils with the same width and the same post-processing code in a descending order of their thicknesses; and then sequencing the coils with the same post-processing code, the same width and the same thickness in a descending order of their annealing temperatures; an initial coil schedule in the hot galvanizing line is obtained by selecting the coils to be processed in hot galvanizing line from the initial coil schedule in acid rolling line, sequentially inserting them after the initial schedule of the coils in the material inventory of hot galvanizing line; Step 3-5: determine an initial schedule of coils in the hot galvanizing and aluminizing line: an initial schedule of coils in material inventory of the hot galvanizing and aluminizing line is obtained, by sequencing the coils in material inventory of the hot galvanizing and aluminizing line in a descending order of their post-processing codes; and then sequencing the coils with the same post-processing code in a descending order of their widths; and then sequencing the coils with the same post-processing code and the same width in a descending order of their thicknesses; and then sequencing the coils with the same post-processing code, the same width and the same thickness in a descending order of their annealing temperatures; an initial coil schedule in the hot galvanizing and aluminizing line is obtained, by selecting the coils to be processed in hot galvanizing and aluminizing line from the initial coil schedule in acid rolling line, sequentially inserting them after the initial schedule of coils in material inventory of the hot galvanizing and aluminizing line; Step 3-6: calculating the starting time of each coil in the initial coil schedule in the continuous annealing line, the starting time of each coil in the initial coil schedule in the hot galvanizing line, and the starting time of each coil in the initial coil schedule in the hot aluminizing and galvanizing line; Step 3-7: recording an initial coordinated coil schedule of multiple production lines in the cold rolling area, and calculating the objective function value corresponding to the initial coordinated coil schedule of multiple lines in the cold rolling area; Step 4: improving in real time the initial coordinated coil schedule of multiple lines in the cold rolling area; Step 5: sending the improved coordinated coil schedule of multiple lines in the cold rolling area to an automatic control systems (ACS) of each production lines in the cold rolling area, and realizing the coordinated coil scheduling of multiple lines in the cold rolling area, wherein realizing the coordinated coil scheduling includes: wherein the coordinated coil scheduling improves the quality of the product by having reduced equipment adjustment and reduced abrasion penalties.