Investigation On Petri Nets Model And Software Design On Simulation Of Logistics System In Steelmaking Process

Steel-making process is key process in steel manufacture process. It is essential for someone to make reasonable planning and scheduling in order to achieve production of smooth logistics, quality steel and efficient cost. Simulation is a process to simulate real world with the help of model. Simulating the logistics in steel-making process is beneficial to preparation of reasonable plan and scheduling scheme for the process. Petri net has widely been used in simulation for logistics system because of its visualization in results and strictness in principles. In this thesis, a model based on timed and colored Petri Nets has been built up to simulate the logistics in steel making process. A software package has been designed and developed based on the model by using object-oriented methodology. The package has also been validated based on investigation on simulating the logistics in The Vanadium-extracting and Steel-making Plant of Panzhihua Iron and Steel Corporation.It is shown that the software can be used to build the entity and timed and colored Petri nets model for simulating logistics in steel-making process with its friendly interface and usage, reasonable functions, strong extendibility and easy maintenance. It has also been shown that the generator of random number in the software can used to simulate the distribution of processing time in real process. When input is similar, out of simulation is, in the main, consistent with logistics in real world. When the data of logistics in current process are used for input of simulating logistics in future 100% continuous casting process, supply of hot metal from iron-making process may not satisfy the needs of 100% continuous casting on raw materials. Because planning scheme in continuous casting process depends greatly on smelting scheme in convertor vessel, it is important for operator to balance raw materials supply, smelting and casting in order to realize the scheme of 100% continuous casting. When some equipment are work abnormally, mixer of hot metal and LF furnace can be used for logistics buffer. The processing time has to be extended so that malfunction of equipment is trouble shoot and disturbance in process are recovered.The logistics model of steel-making process based on the timed and colored Petri Nets can reproduce and simulate real logistics process whatever it works normally or abnormally. The simulation will provide decision-making support on planning,scheduling working procedure and optimizing logistics in steel-making process.