机电技术专业英语 教学课件 作者 徐起贺 张庆良pata a lesson Twenty three.pptVIP

* 机电技术专业英语 Lesson Twenty-three Text Flexible manufacturing is one of the most exciting emerging automation concepts. In order to understand this concept, we must discuss automation in general. As we know, mechanization started with the industrial revolution, when machines performed some of the functions of labor. Automation included mechanization and went beyond it. With the twentieth century came a new concept, mass production, the automation technology then available, i.e., the assembly line, markedly increased the productivity of workers and resulted in economic prosperity. In fact, both the assembly line and the transfer line belong to the domain of fired automation, in which the sequence of processing operations remains unchanged throughout the production run because the sequence of operations is determined mainly by the nature and arrangement of the physical equipment in the production Flexible Manufacturing Systems Lesson Twenty-three line, which, once established, cannot usually be changed, except with great difficulty. It can, therefore, be seen that the fixed automation, which is based on integrating and coordinating simple operations, has three characterizing features. First, it requires very high initial capital cost; second, it is suitable only for high production volume (to pay back for its high capital cost); and third, it is inflexible and cannot handle product changeover or even major changes in the product design. Lesson Twenty-three New Words and Expressions Lesson Twenty-three New Words and Expressions Lesson Twenty-three Notes 1.…is to plot the different shapes (or designs) of parts that the automated system can tolerate versus the production volume. …是图示对比一下该种自动化系统能够生产的产品与其能达到的产量之间的差异。 2….which also shows the recommended successful domain for each of the two automated systems . …同时也表明了这两种自动化系统各自的最佳范畴。 3….because of the need for insurance against unexpected circumstances , which calls for flexibility and the tai