嘻嘻，难得的ED案例哦！ case 1 the production line.docVIP

Case study 1: the production line Introduction In flow line production, the production equipment is laid out in the production sequence. The products usually follow the same route through the system. This type of system is frequently very sensitive to equipment breakdowns, because if one process stops, this stops the entire line. Having stock between each process can reduce this sensitivity. Flow line systems are most useful for medium to long production runs. 1.2 Description of the situation A factory producing a range of vehicles is considering adding a new high quality trailer to the range. Because a competitor has ceased to trade, it is believed that substantial sales can be expected over the coming years. To meet this anticipated demand, a new assembly line is planned which will be equipped mainly with robots. The trailer assembly can be divided into five main operations. A single robot carries out each operation. At the first operation (A), the axles and wheels are fitted to the frame. This is followed by mounting the underside onto the frame (B). The vehicle sides are then attached (C) followed by the roof (D). The final assembly operation and quality check (E) is not automated, as customers often have special requirements. See figure 1.1 Figure 11: The production line All the parts used for the assembly are standard. There are several types of some parts, but these have no effect on the processing speed. Also, there is always an adequate stock of parts to supply the line. Although the first four processes are fully automated, it has not been possible to synchronize them precisely. Axle to frame assembly (A) takes an average of 15 minutes, as does attaching the underside to the frame (B). Assembling the sides to the frame (C) requires an average of 18 minutes, and the roof assembly (D) is a precision process and only three trailers per hour can be completed. Final assembly and quality check (E) is a manual operation and take an av