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1、<p><b>  外文翻譯 </b></p><p>  The Computer and Manufacturing</p><p>  The computer is bringing manufacturing into the Information Age.This new tool, long a familiar one in busin

2、ess and management operations, is moving into the factory, and its advent is changing manufacturing as certainly as the steam engine changed it 100 years ago.</p><p>  The basic metal working processes are n

3、ot likely to change fundamentally, but their organization and control definitely will.</p><p>  IN one respect, manufacturing could be said to be coming full circle. The first manufacturing could was a cotta

4、ge industry: the designer was also the manufacturer, conceiving and fabricating products one at a time. Eventually, the concept of the interchangeability of parts was developed, production was separated into specialized

5、functions, and identical parts were produced thousands at a time.</p><p>  Today, although the designer and manufacturer may not become one again, the functions are being drawn close in the movement toward a

6、n integrated manufacturing system,</p><p>  It is perhaps ironic that, at a time when the market demand a high degreed of product diversification, the necessity for increasing productivity and reducing costs

7、 is driving manufacturing toward integration into a coherent system, a continuous process in which parts do not spend as much as 95% of production time being moved around or waiting to be worked on.</p><p> 

8、 The computer is the key to each of these twin requirements. It is the only tool that can provide the quick reflexes, the flexibility and speed, to meet a diversified market. And it is the only tool that enables the deta

9、iled analysis and the accessibility of accurate data necessary for the integration of the manufacturing system. </p><p>  It may well be that, in the future, the computer may be essential to a company’s surv

10、ival. Many of today’s businesses will fade away to be replaced by more-productive combinations. Such more-productive combinations are superquality, superproductivity plants. The goal is to design and operate a plant that

11、 would produce 100% satisfactory parts with good productivity.</p><p>  A sophisticated, competitive world is requiring that manufacturing begin to settle for more, to become itself sophisticated, To meet co

12、mpetition, for example, a company will have to meet the somewhat conflicting demands for greater product diversification, higher quality, improved productivity, and low prices.</p><p>  The company that seek

13、s to meet these demands will need a sophisticated tool, one that will allow it to respond quickly to customer needs while getting the most out of its manufacturing resources.</p><p>  The computer is that to

14、ol.</p><p>  Becoming a “superquality, superproductivity” plant requires the integration of an extremely complex system. This can be accomplished only when all elements of manufacturing—design, fabrication a

15、nd assembly, quality assurance, management, materials handling—are computer integrated.</p><p>  In product design, for example, interactive computer-aided-design (CAD) systems allow the drawing and analysis

16、 tasks to be performed in a fraction of the time previously required and with greater accuracy. And programs for prototype testing and evaluation further speed the design process.</p><p>  In manufacturing p

17、lanning, computer-aided process planning permits the selection, from thousands of possible sequences schedules, of the optimum process.</p><p>  On the shop floor, distributed intelligence in the form of mic

18、roprocessors controls machines, runs automated loading and unloading equipment, and collects data on current shop conditions.</p><p>  But such isolated revolutions are not enough. What is needed is a totall

19、y automated system, linked by common software from front door to back.</p><p>  The benefits range throughout the system. Essentially, computer integration provides widely and instantaneously available, accu

20、rate information, improving communication between departments, permitting tighter control, and generally enhancing the overall quality and efficiency of the entire system.</p><p>  Improved communication can

21、 mean, for example, designs that are more producible. The NC programmer and the tool designer have a chance to influence the product designer, and vice versa.</p><p>  Engineering changes, thus, can be reduc

22、ed, and those that are required can be handled more efficiently. Not only does the computer permit them to be specified more quickly, but it also alerts subsequent users of the data to the fact that a change has been mad

23、e.</p><p>  The instantaneous updating of production-control data permits better planning and more0effective scheduling. Expensive equipment, therefore, is used more productively, and parts move more efficie

24、ntly through production, reducing work-in-process costs.</p><p>  Product quality, too, can be improved. Not only are more-accu-rate designs produced, for example, but the use of design data by the quality-a

25、ssurance department helps eliminate errors due to misunderstandings.</p><p>  People are enabled to do their jobs better. By eliminating tedious calculations and paperwork—not to mention time wasted searchin

26、g for information—the computer not only allows workers to be more productive but also frees them to do what only human beings can do: think creatively.</p><p>  Computer integration may also lure new people&

27、#160; into manufacturing. People are attracted because they want to work in a modern, technologically sophisticated environment.</p><p>  In manufacturing engineering, CAD/CAM decreases tool-design.NC-progra

28、mming, and planning times while speeding the response rate, which will eventually permit in-house staff to perform work that is currently being contracted out.</p><p>  According to the Tool & Manufactur

29、ing Engineers Handbook, process planning is the systematic determination of the methods by which a product is to be manufactured economically and competitively. It essentially involves selection, calculation, and documen

30、tation. Processes, machines, tools, and sequences must be selected. Such factors as feeds, speeds, tolerances, dimensions, and costs must be calculated. Finally, documents in the form of setup instructions, work instruct

31、ions, illustrated process </p><p>  Most manufacturing engineers would agree that, if ten different planners were asked to develop a process plan for the same part, they would probably come up with ten diffe

32、rent plans. Obviously, all these plans cannot reflect the most efficient manufacturing methods, and, in fact, there is no guarantee that any one of them will constitute the optimum methods for manufacturing the part.<

33、/p><p>  What may be even more disturbing is that a process plan developed for a part during a current manufacturing program may be quite different manufacturing program and it may never be used again for the s

34、ame or similar part during a previous similar part. That represents a lot of wasted effort and produces a great many inconsistencies in routing, tooling, labor requirements, costing, and possibly even purchase requiremen

35、ts.</p><p>  Of course, process plans should not necessarily remain static. As lot sizes change and new technology, equipment, and processes become available, the most effective way to manufacture a particul

36、ar part also changes, and those changes should be reflected in current process plans released to the shop.</p><p>  A planner must manage and retrieve a great deal of data and many documents, including estab

37、lished standards, machinability data, machine specifications, tooling inventories, stock availability, and existing process plans. This is primarily an information-handling job, and the computer is an ideal companion.<

38、;/p><p>  There is another advantage to using computers to help with process planning. Because the task involves many interrelated activities, determining the optimum plan requires many iterations. Since comput

39、ers can readily perform vast numbers of comparisons, many more alternative plans can be explored than would be possible manually.</p><p>  A third advantage in the use of computer-aided process planning is u

40、niformity.</p><p>  Several specific benefits can be expected from the adoption of computer-aided process-planning techniques:</p><p> ?。?、    Reduced clerical effort in preparatio

41、n of instructions.</p><p> ?。?、    Fewer calculation errors due to human error.  Fewer oversights in logic or instructions because of the prompting capability available with interactive co

42、mputer programs.</p><p> ?。?、     Immediate access to up-to-date information from a central database.   Consistent information, because every planner accesses the same datab

43、ase.</p><p> ?。础?#160;   Faster response to changes requested by engineering of other operating departments.</p><p> ?。?、    Automatic use of the latest revision of a par

44、t drawing.</p><p>  6、    More-detailed, more-uniform process-plan statements produced by word processing techniques.</p><p> ?。?、     More-effective use of inv

45、entories of tools, gages, and fixtures and a concomitant reduction in the variety of those items.</p><p>  8、   Better communication with shop personnel because plans can be more specifically tailo

46、red to a particular task and presented in unambiguous, proven language.</p><p>  9、     Better information for production planning, including cutter-life, forecasting, materials-requireme

47、nts planning, scheduling, and inventory control.</p><p>  Most important for CIM, computer-aided process planning produces machine-readable data instead of hand written plans. Such data can readily be transf

48、erred to other systems within the CIM hierarchy for use in planning.</p><p>  There are basically two approaches to computer-aided process planning: variant and generative.</p><p>  In the varia

49、nt approach, a set of standard process plans is established for all the parts families that have been identified through group technology. The standard plans are stored in computer memory and retrieved for new parts acco

50、rding to their family identification. Again, GT helps to place the new part in an appropriate family. The standard plan is then edited to suit the specific requirements of a particular job.</p><p>  In the g

51、enerative approach, an attempt is made to synthesize each individual plan using appropriate algorithms that define the various technological decisions that must be made in the course of manufacturing. In a truly generati

52、ve process-planning system, the sequence of operations, as well as all the manufacturing-process parameters, would be automatically established without reference to prior plans. In its ultimate realization, such an appro

53、ach would be universally applicable: present any pla</p><p>  No such system exists, however. So called generative process-planning system—and probably for the foreseeable future—are still specialized system

54、s developed for a specific operation or a particular type of manufacturing process. The logic is based on a combination of past practice and basic technology.</p><p><b>  計(jì)算機(jī)與制造業(yè)</b></p>&

55、lt;p>  計(jì)算機(jī)正在將制造業(yè)帶入信息時代。計(jì)算機(jī)長期以來在商業(yè)和管理方面得到了廣泛的應(yīng)用,它正在作為一種新的工具進(jìn)入到工廠中,而且它如同蒸汽機(jī)在100年前使制造業(yè)發(fā)生改變那樣,正在使制造業(yè)發(fā)生著變革。</p><p>  盡管基本在金屬切削過程不太可能發(fā)生根本性的改變,但是它們的組織形式和控制必將發(fā)生改變。</p><p>  從某一方面可以用說,制造業(yè)正在完成一個循環(huán)。最初的制

56、造業(yè)是家庭手工業(yè):設(shè)計(jì)都本身也是制造者,產(chǎn)品的構(gòu)思與加工由同一個人完成,后來,形成了零件的互換性這個概念,生產(chǎn)被依照專業(yè)功能分割開來,可以用成批生產(chǎn)數(shù)以千計(jì)的零件。</p><p>  今天,盡管設(shè)計(jì)者與制造者不可能再是同一個人,但在向集成制造系統(tǒng)前進(jìn)的途中,這兩種功能已經(jīng)越來越近了。</p><p>  可能具有諷刺意味的是,在市場需求高度多樣化的時候,提高生產(chǎn)率和降低成本的必要性促使著

57、制造業(yè)朝著集成為緊湊的系統(tǒng)方向變化。這是一個連續(xù)的過程,在其中零件不需要花費(fèi)多達(dá)95%的生產(chǎn)時間用在運(yùn)輸和等待加工上。</p><p>  計(jì)算機(jī)是滿足這兩項(xiàng)要求中任何一項(xiàng)的關(guān)鍵。它是能夠提供快速反應(yīng)能力、以性和來滿足多樣化市場的唯一工具。而且,它是實(shí)現(xiàn)制造系統(tǒng)集成所需要的、能夠進(jìn)行詳細(xì)分析和利用精確數(shù)據(jù)的唯一工具。</p><p>  在將來計(jì)算機(jī)可能會是一個企業(yè)生存的基本條件,許多現(xiàn)今

58、的企業(yè)將會被生產(chǎn)能力更高的企業(yè)組合所取代。這些生產(chǎn)能力更高的企業(yè)組合是一些具有非常高的質(zhì)量、非常高的生產(chǎn)率的工廠。目標(biāo)是設(shè)計(jì)和運(yùn)行一個能夠以高生產(chǎn)率的方式生產(chǎn)100%合格產(chǎn)品的工廠。</p><p>  一個采用先進(jìn)技術(shù)的、競爭的世界正在促使制造業(yè)開始做更多的工作,使其本身采用起早摸黑技術(shù)。為了適應(yīng)競爭,一個公司會滿足一些在某種程度上相互矛盾的要求,諸如產(chǎn)品多樣化、提高質(zhì)量、增加生產(chǎn)率、降低價格。在努力滿足這些要

59、求的過程中,公司需要一個采用先進(jìn)技術(shù)的工具,一個能夠?qū)︻櫩偷男枨笞鞒隹焖俜磻?yīng),而且從制造資源中獲得最大收益的工具。</p><p>  計(jì)算機(jī)就是這個工具。</p><p>  成為一個具有“非常高的質(zhì)量、非常高的生產(chǎn)率”的工廠,需要對一個非常復(fù)雜的系統(tǒng)進(jìn)行集成。這只有通達(dá)采用計(jì)算機(jī)對機(jī)械制造的所有組成部分——設(shè)計(jì)、加工、裝配、質(zhì)量保證、管理和材料裝卸及輸送進(jìn)行集成電路才能完成。</

60、p><p>  例如,在產(chǎn)品設(shè)計(jì)期間,人機(jī)對話式的計(jì)算機(jī)輔助設(shè)計(jì)系統(tǒng)使得完成任務(wù)給圖和分析工作所需要的時間比原來減少了幾倍,而且精確程度得到了很大的提高。此外樣機(jī)的試驗(yàn)與評價程序進(jìn)一步加快了設(shè)計(jì)過程。</p><p>  在制訂工藝規(guī)程時,計(jì)算機(jī)輔助編制工藝規(guī)程可以從數(shù)以千計(jì)的工序和加工過程中選擇最好的加工方案。</p><p>  在車間里,許多獨(dú)立的微型計(jì)算機(jī)在控制

61、著機(jī)床,操縱著自動裝卸材料設(shè)備和收信關(guān)于當(dāng)前車間狀態(tài)的信息。</p><p>  但是這些各自獨(dú)立的改革還遠(yuǎn)遠(yuǎn)不夠。我們所需要的是由一個共同的軟件從始端到終端進(jìn)行控制的全部自動化的系統(tǒng)。</p><p>  整個系統(tǒng)都會從中受益?;旧?,計(jì)算機(jī)集成可以提供廣泛的。及時的和精確的信息,可以改進(jìn)各部門之間的交流和磋商,實(shí)施更嚴(yán)格的控制,而且通常能增強(qiáng)整個系統(tǒng)的全面質(zhì)量和效率。</p>

62、;<p>  例如,改進(jìn)交流和磋商意味著會使設(shè)計(jì)具有更好的可制造性。數(shù)控編程人員和工藝裝備設(shè)計(jì)人員有機(jī)會向產(chǎn)品設(shè)計(jì)人員提出意見,反之亦然。</p><p>  因而可以減少技術(shù)方面的變更,而對于那些必要的變更,可以更有效地進(jìn)行處理。計(jì)算機(jī)不公能夠更快地對變更之處作出詳細(xì)說明,而且還能能把變更之后的數(shù)據(jù)告訴隨后的使用者。利用即時更新的生產(chǎn)控制數(shù)據(jù)可以制訂更好的工藝規(guī)程和更有效率的生產(chǎn)進(jìn)度。因而,可以使

63、昂貴的設(shè)備得到更好的利用,提高零件在生產(chǎn)過程中的運(yùn)送效率,減少加工成本。產(chǎn)品質(zhì)量也可以得到改進(jìn)。例如,不公可以提高設(shè)計(jì)精度,還可以使質(zhì)量保證部門利用設(shè)計(jì)數(shù)據(jù),避免由于隔閡而產(chǎn)生錯誤。</p><p>  可以使人們更好地完成他們的工作。通過避免冗長的計(jì)算和書寫工作——這還不算查找資料所浪費(fèi)的時間——計(jì)算機(jī)不僅使人們更有效地工作,而且還能把他們解放出來去做只有人類才能做工作:創(chuàng)造性地思考。</p>&

64、lt;p>  計(jì)算機(jī)集成制造還會吸引新的人才進(jìn)入制造業(yè)。人才被吸引過來的原因是他們希望得到一個現(xiàn)代化的。技術(shù)先進(jìn)的環(huán)境中工作。在制造工程中,CAD/CAM減少了工藝裝備設(shè)計(jì)。數(shù)控編程和編制工藝規(guī)程所需要的時間。而且,在同時加快了響應(yīng)速度,這最終將會使目前外加式的工作由公司內(nèi)部人員來完成。</p><p>  根據(jù)《工具與制造工程手冊》,工藝過程是能夠經(jīng)濟(jì)地和有競爭力地將產(chǎn)品制造出來的一整套的方法。它主要由選

65、擇、計(jì)算成本和建立工藝文件組成。對加工方法、機(jī)床、刀具、工序和順序必須進(jìn)行選擇。對于一些參數(shù)如進(jìn)給量、速度、公差、尺寸和成本等應(yīng)該進(jìn)行計(jì)算。最后,應(yīng)該建立工作過程安排、加工說明、帶工序簡圖的工藝過程卡片和加工路線等方面的工藝文件。工藝過程是產(chǎn)品設(shè)計(jì)和制造的中間環(huán)節(jié)。那么,它是如何將設(shè)計(jì)與制造連接起來的呢?</p><p>  大部分制造工程師都會同意這個看法,即如果10個不同的工藝人員編制同一個零件的工藝規(guī)程,他

66、們很可能得出10種不同的方案。顯然,所有這些方案都不能反映最適當(dāng)?shù)闹圃旆椒?,而且,事?shí)上也不能保證它們中的任何一個方案是由加工這個零件的最好的方法組成的。</p><p>  在目前的制造過程中的一個更為混亂的事情是,對于一個零件來說,現(xiàn)在所編制的工藝規(guī)程可能與以前在制造過程中所編制的同一個零件或者相似零件的工藝規(guī)程相差很多,而且這個工藝規(guī)程可能再也不會應(yīng)用于同一個零件或者說相似零件。這說明很多工作都被浪費(fèi)了,而

67、且在工藝路線、工藝裝備、對工人的要求和成本等方面都不一至,甚至對外購件的要求都不一樣。</p><p>  當(dāng)然工藝規(guī)程不應(yīng)該是一成不變的。隨著產(chǎn)品批量的變化和新技術(shù)。新設(shè)備、新的加工方法的出現(xiàn),加工制造某一種特定零件最適當(dāng)?shù)姆椒ㄒ矔l(fā)生變化,而且這些變化應(yīng)該在車間目前使用的加工工藝規(guī)程中反映出來。</p><p>  工藝人員應(yīng)該管理和檢索大量的數(shù)據(jù)和很多文件,其中包括:已經(jīng)建立了的標(biāo)準(zhǔn)

68、、可加工性數(shù)據(jù)、機(jī)器的規(guī)格、工藝裝備的清單、原材料庫存量和一些目前正在應(yīng)用的工藝方件。這主要是一些信息處理工作,而計(jì)算機(jī)是完成這項(xiàng)工作的一個理想助手。</p><p>  在編制工藝水平規(guī)程時計(jì)算機(jī)還有一個優(yōu)點(diǎn)。因?yàn)檫@項(xiàng)工作涉及到許多相互關(guān)聯(lián)的事情,在確定最優(yōu)的方案時,需要進(jìn)行許多次迭代。由于計(jì)算機(jī)可以很容易地進(jìn)行大量的比較工作,它比人工能夠分析的可供選擇的方案要多得多。</p><p>

69、  采用計(jì)算機(jī)輔助編制工藝規(guī)程的第三個優(yōu)點(diǎn)是所編制的規(guī)程具有一致性。</p><p>  采用計(jì)算機(jī)輔助編制工藝規(guī)程可以獲得以下幾點(diǎn)好處:</p><p> ?。?、在準(zhǔn)備工藝文件時,減少了書寫工作量。</p><p> ?。?、 減少了在進(jìn)行人工計(jì)算時所產(chǎn)生的錯誤。由于交互式計(jì)算機(jī)程序的提示功能而減少了邏輯和說明方面的疏漏。</p><p> 

70、?。?、 通過中心數(shù)據(jù)庫可以直接利用最新的信息。由于第一個工藝人員都利用相同之處的數(shù)據(jù)庫,因此,可以保證信息的一致性。</p><p> ?。?、 對由其他部門的工程人員所提出的修改意見作出快速反應(yīng)。</p><p> ?。?、 自動地利用最新版本的零件圖紙。</p><p>  6、 采用方字處理技術(shù),產(chǎn)生更詳細(xì)、更一致的工藝文件。</p><p&g

71、t; ?。?、 更有效地利用庫存的刀具、量具、夾具,減少這些物品的和數(shù)。</p><p> ?。?、 由于能夠使工藝規(guī)程適合于某一項(xiàng)特定的工作,面具最清楚的。有理有據(jù)的語言表達(dá)出來,因此可以與車間的人員進(jìn)行更好的交流。</p><p>  9、 可以用更好地獲得編制工藝規(guī)程所需的信息,其中包括:刀具壽命、預(yù)測、材料需求計(jì)劃、進(jìn)度和庫存控制。對計(jì)算機(jī)集成制造最為重要的是,計(jì)算機(jī)輔助編制規(guī)程可以生

72、成機(jī)器可以閱讀的數(shù)據(jù),而不是手寫的規(guī)程。這種數(shù)據(jù)可以傳遞到計(jì)算機(jī)集成電路制造體系中的另一個系統(tǒng)中,用以編制工藝規(guī)程。計(jì)算機(jī)輔助編制工藝規(guī)程通常有兩種類型:派生式和創(chuàng)成式。在派生中,對采用成組技術(shù)確定的一個零件族中的所有零件編制一套標(biāo)準(zhǔn)的加工工藝規(guī)程。這個標(biāo)準(zhǔn)工藝規(guī)程存貯在計(jì)算機(jī)的存儲器中,根據(jù)新零件的零件族代號進(jìn)行檢索。成組技術(shù)可以幫助把新零件歸類于適當(dāng)?shù)牧慵迳?。通過對標(biāo)準(zhǔn)工藝規(guī)程的編輯,可以滿足選定工作的專門要求。在創(chuàng)成式中,通過采

73、用確定加工制造過程中各種工藝決策的適當(dāng)算法,將各個單獨(dú)的工藝規(guī)程綜合起來。在一個真正的創(chuàng)成式計(jì)算機(jī)輔助編制工藝規(guī)程系統(tǒng)中,工序的排列和所有的加工過程參數(shù)都可以在不用參考以前的工藝堆積的情況下自動生成。在它最終實(shí)現(xiàn)之后,這種方式將會是普遍適用的:將任何一個計(jì)劃提交給這個系統(tǒng),計(jì)算機(jī)都會產(chǎn)生最優(yōu)的工藝規(guī)程。</p><p>  然而,這種系統(tǒng)目前還不存在。所謂的創(chuàng)成式計(jì)算機(jī)輔助編制工藝系統(tǒng)大概在可以預(yù)料到的將來仍然是

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