Research Article

Integrated Scheduling for Steelmaking Continuous Casting— Hot Rolling Processes considering Hot Chain Logistics

Table 1

Indices, sets, parameters and decision variables.

SymbolDescription

Index set of heats,
Index of heat,
Index set of slabs,
Index of slab, ; the index is sorted according to times when slabs are cut in chronological order
Sub index set of slabs contained in heat ,
Casting duration of slab of heat
Index of processes, , process 1 is steelmaking, process 2 is LF refining, process 3 is RH refining, and process 4 is continuous casting
Index set of machines in process ,
Index of machine,
Processing time of heat on machine
Heat casting sequence relationship. when the heat is casted immediately after heat , otherwise
Minimum/maximum delay from machine to machine
Processing time of slab in HR process
Minimum/maximum delay between two continuously rolled slabs
Shortest delivery time from the position where slab is cut to reheating furnace
Minimum residence time of slab in reheating furnace
Slab rolling sequence relationship; when Slab is rolled immediately after slab , otherwise

, if heat is assigned to machine , and , otherwise,
if Heat and heat are assigned on the same machine and heat is processed before heat , and , otherwise,
Start time of heat in process ,
Time when slab is cut,
Time when slab is charged into reheating furnace
The latest finish time of all heats in the continuous casting process
The latest finish time of all slabs in the HR process