ABSTRACT
Manufacturing processes can be categorized into two broad groups: discrete parts assembly manufacturing and process industry manufacturing. Assembly manufacturing generally consists of the manufacture of individual parts and components that operators and machines then weld, bolt, or otherwise fasten together into a finished product. It can take several attempts at fine-tuning before the line operates smoothly. Both changeover difficulty and restart difficulty can be significant enough to have a strong influence on scheduling, and any strategy should try to minimize these difficulties by sequencing products as similar to the previous product as possible. Some plants run regular sanitation cycles, such as the third shift every night, or on Saturday and Sunday on alternate weekends. A key difference between the two is that the number of different part types converges as material flows through an assembly operation, while the product variety increases as material flows through a process operation.
