| Our manufacturing world continues to become more complex brought about principally by global competition, cost and profitability pressures, and rapidly advancing technology. Flexible manufacturing systems represent an avenue of change for manufacturers that helps to bridge the gap between technology, competition, and profitability through a highly specialized and focused approach to manufacturing effectiveness.FMS is a technique highly dense and sophisticated automation system composed by material flow and information flow. It is very difficult to obtain benefits from machining process because the resources and the machining abilities of every machine have been fixed. The material flow, however, is an aspect that we can research and explore with potential benefits. Studies indicate that in a typical manufacturing operation only 5 percent of a part's total time in manufacturing is used on machining. The other 95 percent of the time the part is either moving through the shop or waiting in queue for the next operation. Therefore, the research of material flow is an important means to improve production efficiency, increase machine availability and lower production cost. Simulation, particularly relative to material flow systems, affords users the opportunity to know and ameliorate the systems. And it has comprehensive applications in material flow systems planning and designing, material flow controlling, and material transportation scheduling.In this dissertation, we explore the FMS material flow systems from modeling and simulation. In modeling, we investigate FMS material flow system based on stochastic high level petri net model, and use stochastic high level petri net modeling method to model the material flow system of Baosteel Tube Branch High-Pressure Boiler Tube (HPBT) production line. In simulation, we bring up a new simulation algorithm based on Event-Oriented Scanning strategy, investigate Object-Oriented based description of stochastic high level petri net model, and finally design and develop High-Pressure Boiler Tube production line material flow simulator based on SHLPN model under the new simulation algorithm.The main contributions of this dissertation is listed below in order oftheir appearances in the paper:1, Discuss the institutes of flexible manufacturing systems and the its importance in industry, the importance of material flow simulation and its present methods in flexible manufacturing systems, and the fruitful results of petri net development and its applications in material flow simulation.2. Analyze the developing course of petri net theory, classify petri net into high level petri net and time related petri net. Investigate the theory of stochastic high level petri net. Lay the foundation for the establishment of FMS material flow systems based on petri net model.3. Aiming at flexible feature and time characteristic of FMS material flow systems, we analyze three modeling methods for FMS components, indicate that petri net modeling has many advantages compared with other methods, and establish the global petri net model of FMS. Finally, we discuss the relationship between FMS model and FMS material flow simulation.4. Propose a new simulation algorithm based on Event-Oriented Scanning strategy under the analysis of material simulator simulation algorithm methods. It is particularly suitable for petri net models. We use scanning way to test the entity (named as transition in petri net) in systems. Once it meets preconditions the activity routine of entity will be fired. So as to related events can happen and system status can be changed. It is not necessary to build simulation clock because of the use of thread. It looks like events can happen simultaneously in the simulator, just as they happen in real production process.5. Describe the technical process of Baosteel Tube Branch HPBT production line and investigate the material flow features of the line. Design and develop a material flow simulator for the HPBT production line based on E-0 scanning simulati...
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