机械工程英语第二部分翻译(共3页).doc

精选优质文档-倾情为你奉上Unit 6Group TechnologyGroup technology is a manufacturing philosophy that involves identifying and grouping components having similar or related attributes in order to take advantage of their similarities in the design and/or manufacturing phases of the production cycle.（成组技术是一个制造业的哲学概念，它涉及到具有相似或相关属性零件的标识和分组，这样我们可利用产品的相似性这种特点，把这种技术应用于产品生产的设计制造过程中）Historically, this novel principle first came into being here in the United States in 1920,when Frederick Taylor supported the idea of grouping parts that required special operations.（历史上，这个新颖的理论是在1920年Frederick Taylor支持将需要特殊加工的零件成组而被第一次提出的）He was followed by the Jones and Lamson Machine Company in the early 1920s,which used a crude form of group technology to build machine tools.（在1920年早期，Jones andLamson公司继承他的思想，他们用粗糙的成组技术形式生产工具）Their manufacturing approach involved such principles as departmentalization by product rather than by process and minimizing the routing paths.（他们使用这一原理的生产方法就是以产品来划分部门，而不是以工艺或缩短路径来划分部门）Today, group technology is implemented through the application of well-structured classification and coding systems and supporting software to take advantage of the similarities of components.（现在，成组技术正在通过运用结构分类、代码系统和支持软件来利用相似零件的优势进一步实施）Reasons for Adopting Group TechnologyModern manufacturing industries are racing a lot of challenges caused by growing international competition and fast-changing market demands. These challenges, which are exemplified in the following list, have been and can be successfully met by group technology:（现在制造工业正在接受由日益激烈的国际化竞争和多变的市场要求带来的挑战。这些挑战可以用成组技术成功地解决，如下所列：）*There is an industrial trend toward low-volume production(small lot sizes)of a wider variety of products in order to meet the rising demand for specially ordered products in today's affluent societies. In other words, the share of the batch-type production in industry is growing day after day, and it is anticipated that 75 percent of all manufactured parts will be in small lot sizes.（工业生产发展的趋势是产品的品种更加多样而每种产品生产的数量减少，以此来满足当今繁荣社会不断增长的专门订货。换句话说，工厂中分批式生产的比例越来越高，预计将来全部的75%是小批量的。）*As a result of the first factor, the conventional shop organization is becoming very inefficient and obsolete because of the wasteful routing paths of the products between the various machine tool departments.（作为第一个因素的结果，传统的车间机构变得越来越低效和过时，因为产品在不同的工具部传送的时候浪费时间）*There is a need to integrate the design and manufacturing phases in order to cut short the lead time, thus winning a competitive situation in the international market.（有必要把设计和制造的阶段集成在一起可以减少订货至交货的时间，这样可以在国际化市场上具有竞争力）Benefits of Group Technology(1)Benefits in product design.（在产品设计的优势）Concerning design of products, the principal benefit of group technology is that it enables product designers to avoid "reinventing the wheel", or duplicating engineering efforts. （关于产品的设计，成组技术最主要的好处在于可以防止重复发明和复制工程成果）In other words, it eliminates the possibility of designing a product that was previously designed because it facilitates storage and easy retrieval of engineering designs.（换句话说，由于它存储方便，并且相关的工程设计很容易被取出，所以消除了发明以前就存在的产品）When an order of a part is released, the part is first coded, and then existing designs that match that code are retrieved from the company's library of designs stored in the memory of a computer, thus saving a large amount of time in design work. （一旦要求设计某一个零件，这个零件首先被编码，然后检索存储于计算机存储器中的该公司的设计库，找出与这个编码相匹配的已有设计，这样便可节省大量的重复设计时间）If the exact part design is not included in the company's computerized files, a design close enough to the required one can be retrieved and modified in order to satisfy the requirements,（如果在公司计算机存储器中没有完全吻合的设计，那就找出与之最相似的设计，修正后可以满足要求）A further advantage of group technology is that it promotes standardization of production tools and work-holding devices.（此外，成组技术可以促进生产工具和工件夹持装置的标准化）(2)Standardization of tooling and setup. （加工和装配的标准化）Since parts are grouped into families, a flexible design for a work-holding device(jig or fixture)can be made for each family in such a manner that it can accommodate every member of that family, thus reducing the cost of fixturing by reducing the number of fixtures required.（因为工件被分成了类别，对工件夹持装置的灵活设计可以应用于每个类的所有零件，这样可以减少所需要的夹持件的数量，从而减少了夹持装置的费用）Also, it is obvious that a machine setup can bemade once for the whole family(because of the similarities between the parts of a family)instead of a machine setup for each of the individual parts.（并且，很显然一次的机器装配可以用于此类的所有零件，而不是只对单个零件适用）(3)More efficient material handling. （更高效的物料输送）When the plant layout is based on the group technology principles, i. e, dividing the plant into cells, each consisting of a group of different machine tools and wholly devoted to the production of a family of parts, material handling is more efficient because of the minimal routing paths of parts between machine tools achieved in this case. （基于成组技术原理规划工厂布局，即把工厂分为单元，每个单元由一组用于生产同一族零件的各种机床组成，这时原材料的传送是很有效的，因为这种情形下的零件在机床间的移动路径最短。）This is in contrast with the "messy" flow lines in the case of the conventional departmentalization-by-process layout. That comparison is clearly illustrated in Fig.6.1,which indicates both cases.（这与传统的按工序分部门的很乱的布局形成了对比！）(4)Improving economies of batch-type production.(提高分批式生产的经济效益)Usually, batch-type production involves a wide variety of nonstandard parts, seemingly with nothing in common. （通常，分批式生产包括各种各样的不标准零件，貌似它们没有共性）Therefore, grouping parts(and processes)in families enable to achieve economies that are obtainable only in mass production.（但是，分组技术只有在大量生产时才可以取得经济效益）(5)Easier scheduling.（更容易安排）Grouping the parts into families facilitates the task of scheduling, since this work will be done for each family instead of for each part.（将工件分族可以降低安排任务的难度）(6)Reduced work-in-process and lead time.（减少在制品和订货至交货的时间）Reduced work-in-process(WIP)and lead time result directly from reduced setup and material-handling time. （WIP源于减少了安装和原材料处理的时间）In other words, parts are not redundantly transferred between machining departments, since material handling is carried out efficiently within each of the individual cells. （换句话说，由于在每个单元之间高效的物料输送，零件在加工部门传送地一点都不冗余）This is in contrast to the production in a typical plant with a process-type layout, where a piece that requires only a few minutes of machining may spend days on the shop floor. （这与本来一个工件可以几分钟加工完的却用了几天的基于过程布局的车间的生产形成了对比，）This latter situation involves increased WIP, which adversely affects the inventory turuover and the cash-flow cycle. （后一种情形下需要较多的在制品，这对库存换新率及现金的周转率产生不利的影响）Also, lead time for a product manufactured in a plant designed according to group technology principles is far shorter than that of a product manufactured in a plant with a process-type layout.（而且，基于成组技术的车间产品的订货至交货的时间比基于过程的车间快得多）(7)Faster and more rational process planning. （更快更理智的过程设计）Group technology paves the way for automated process planning. （成组技术为自动过程设计做好了准备）This can be achieved through proper parts classification and coding system, where a detailed process plan for each part is stored under its code and thus can be easily retrieved.（这可以通过合理的零件分类和编码系统来实现，详细的加工计划储存在编码里面并且很容易被取出）专心-专注-专业