機(jī)械專業(yè)畢業(yè)設(shè)計(jì)外文翻譯--工藝規(guī)程制訂

1、<p><b>　　附錄</b></p><p>　　Process Planning</p><p>　　The product design is the plan for the product and its components and subassemblies.To convert the product design into a physi

2、cal entity ,a manufacturing plan is needed .The activity of developing such a plan is called process planning .It is the link between product design and manufacturing .Process planning involves determining the sequence o

3、f processing and assembly steps that must be accomplished to make the product .In the present chapter ,we examine processing planning and several related </p><p>　　At the outset ,we should distinguish betwee

4、n process planning and production planning ,which is covered in the following chapter. Process planning is concerned with the engineering and technological issues of how to make the products and its parts. What types of

5、equipment and tooling are required to fabricate the parts and assemble the product ? Production planning is concerned with the logistics of making the product .After process planning is concerned with ordering the materi

6、als and obtaining</p><p>　　Process Planning </p><p>　　Process planning involves determining the most appropriate manufacturing and assembly processes and the sequence in which they should be acc

7、omplished to produce a given part or product according to specifications set forth in the product design documentation.The scope and variety of processes that can be planned are generally limited by the available process

8、ing equipment and technological capabilities of the company of plant .Parts that cannot be made internally must be purchased from outside ve</p><p>　　Process planning is usually accomplished by manufacturing

9、 engineers .(Other titles include in industrial engineer.) The process planner must be familiar with the particular manufacturing processes available in the factory and be able to interpret engineering drawings .Based on

10、 the planner’s knowledge,skill,and experience ,the processing steps are developed in the most logical sequence to make each part .Following is a list of the many decisions and details usually include within the scope of

11、pro</p><p>　　.Interpretation of design drawings. The part of product design must be analyzed (materials,dimensions,tolerances ,surface finished,etc.) at the start of the process planning procedure.</p>

12、;<p>　　.Process and sequence. The process planner must select which processes are required and their sequence.A brief description of processing steps must be prepared.</p><p>　　.Equipment selection .

13、 In general , process planners must develop plans that utilize existing equipment in the plant .Otherwise ,the component must be purchased ,or an investment must be made in new equipment .</p><p>　　.Tools ,

14、dies,molds,fixtures,and gages. The process must decide what tooling is required for each processing step.The actual design and fabrication of these tools is usually delegated to a tool design department and tool room ,o

15、r an outside vendor specializing in that type of tool is contacted.</p><p>　　Methods analysis . Workplace layout ,small tools ,hoists for lifting heavy parts ,even in some cases hand and body motions must b

16、e specified for manual operations .The industrial engineering department is usually responsible for this area.</p><p>　　.Work standards. Work measurement techniques are used to set time standards for each o

17、peration .</p><p>　　.Cutting tools and cutting conditions. These must be specified for machining operations ,often with reference to standard handbook recommendations.</p><p>　　Process Planning

18、 for parts</p><p>　　For individual parts,the processing sequence is documented on a form called a route sheet .(Not all companies use the name route sheet ;another name is “operation sheet .”)Just as enginee

19、ring drawings are used to specify the product design ,route sheets are used to specify the process plan .They are counterparts,one for product design ,the other for manufacturing .A typical route sheet ,illustrated in F

20、ig.21.1,includes the following information: (1) all operations to be performed on the work pa</p><p>　　Decisions on process to be used to fabricate a given part are based largely on the starting material for

21、 the part .This starting material is selected by the product designer.Once the material has been specified ,the range of the possible processing operation is reduced considerably .The product designer’s decisions on star

22、ting material are based primarily on functional requirements ,although economics and manufacturability a role in the selection.</p><p>　　A typical processing sequence to fabricate an individual part consists

23、 of : (1) a basic process,(2)secondary processes ,(3) operations to enhance physical properties,and (4)finishing operations.The sequence is shown in Fig.21.2. A basic process determines the starting geometry of the workp

24、art.Metal casting ,plastic molding ,and roling of sheet metal are examples of basic processes.The starting geometry must often be refined by secondary processes,operations that transform the starting geometry (</p>

25、<p>　　Once the geometry has been established ,the next step for some parts is to improve their mechanical and physical properties .Operations to enhance properties do not alter the geometry of the part;instead,the

26、y alter physical properties .Heat treating operations on metal parts are the most common examples .Similar heating treatments are performed on glass to produce tempered glass.For most manufactured parts ,these property-

27、enhancing operations are not required in the processing sequence ,as indi</p><p>　　Finally finish operations usually provide a coat on the work parts (or assembly )surface. Examples inclued electroplating ,t

28、hin film deposition techniques ,and painting.The purpose of the coating is to enhance appearance ,change color ,or protect the surface from corrosion,abrasion ,and so forth .Finishing operations are not required on many

29、parts ;for example, plastic molding rarely require finishing .When finishing is required ,it is usually the final step in the processing sequence .Table 21-</p><p>　　In most cases,parts and materials arrivin

30、g at the factory have complete their basic process.Thus ,the first operation in the process plan follows the basic process that has provided the starting geometry of the part ..For example ,machined parts begain as bar s

31、tock or castings or forgings,which are purchased from outide vendors.The process plan begains with the machining operations in the company’s own plant .Stempings begin as sheet metal coils or strips that are bought from

32、the rolling mill.Th</p><p>　　In addition to the route sheet ,a more detailed description of eac operation is usually prepared. This is filed in the particular production department office where the operation

33、 is performed.It lists specific details of the operation ,such as cutting conditionsand toolings(if the operation is machining )and other instructions that may be useful to the amchine operator.The desciptions often incl

34、ude sketches of the machine setup.</p><p>　　Processing Planning for Assemblies</p><p>　　The type of assembly method used for a given product depends on factors such as : (1) the anticipated prod

35、uction quantities ;(2) complexity of the assembled product ,for example ,the number of distinct components ;and (3)assembly processes used ,for example ,mechanical assembly versus welding .For a product that is to be mad

36、e in relatively small quantities ,assembly is usually performed on manual assembly lines .For simple products of a dozen or so components,to be made in large quantities ,auto</p><p>　　Process planning for as

37、sembly involves development of assembly instructions,but in more detail .For low production quantities,the entire assembly is completed at a single station .For high production on an assembly line ,process planning consi

38、sts of allocating work elements to the individual stations of the line, a procedure called line balancing.The assembly line routes the work unit to individual stations in the proper order as determined by the line balanc

39、e solution.As in process planning for</p><p><b>　　laid out.</b></p><p><b>　　工藝規(guī)程制訂</b></p><p>　　產(chǎn)品設(shè)計(jì)是用于產(chǎn)品,及它的部件裝配的計(jì)劃. 為了把產(chǎn)品設(shè)計(jì)轉(zhuǎn)換成一個(gè)實(shí)際物體 ,這需要一個(gè)制造計(jì)劃。而制訂一個(gè)這樣的計(jì)劃的

40、行動(dòng)就叫做工藝規(guī)程制訂。它是產(chǎn)品設(shè)計(jì)和制造之間的連接.工藝規(guī)程制訂包括決定加工順序和制造產(chǎn)品所必須完成的裝配步驟.在以下文章中,我們將解釋工藝規(guī)程制訂和他的一些相關(guān)主題。</p><p>　　文章開始, 我們應(yīng)該區(qū)別在下列文章中被反復(fù)提到的工藝規(guī)程制訂和生產(chǎn)計(jì)劃。工藝規(guī)程制訂與如何制造產(chǎn)品和它的零件等工程技術(shù)問題有關(guān).制造零件和裝配產(chǎn)品需要什么樣的設(shè)備和工具? 工藝規(guī)程制訂與產(chǎn)品制造物流管理有關(guān)系。它在工藝規(guī)程制

41、訂后面與原料分類及獲得滿足制造充分?jǐn)?shù)量產(chǎn)品要求的資源有關(guān).</p><p><b>　　工藝規(guī)程制訂</b></p><p>　　工藝規(guī)程制訂包括決定最適當(dāng)?shù)闹圃旒把b配步驟和順序,在這些順序和步驟中他們必須根據(jù)所提出的詳細(xì)的設(shè)計(jì)說明書規(guī)范完成給定零件或產(chǎn)品制造. 能夠被計(jì)劃的工藝范圍和多樣性通常由于公司車間可用設(shè)備和技術(shù)能力而受到限制.在公司內(nèi)部不能夠制造的零件必須到

42、外部市場購買. 工藝規(guī)程制訂所提及的工藝選擇同樣也受到詳細(xì)設(shè)計(jì)資料的限制.我們稍后將會(huì)回到這一點(diǎn).</p><p>　　工藝規(guī)程制訂通常是由制造工程師完成的.( 工業(yè)工程師擁有其他權(quán)利.) 工藝制訂者必須熟悉工廠中詳細(xì)可用的制造流程并且能夠說明工程圖?；谥朴喺叩闹R(shí)，技術(shù)和經(jīng)驗(yàn), 用于制造每個(gè)零件的工藝步驟以最合乎邏輯的順序被發(fā)展制訂。下列各項(xiàng)是在工藝規(guī)程制訂范圍里的許多決定和詳細(xì)資料:</p>

43、<p>　　.設(shè)計(jì)圖的說明. 在工藝規(guī)程制訂的開始,產(chǎn)品設(shè)計(jì)的這一部分( 材料，尺寸，公差 ,表面處理,等等)必須進(jìn)行分析。</p><p>　　.工藝和順序. 工藝制訂者必須選擇哪一個(gè)工藝是必需的及必需工藝的序列。此外還必須準(zhǔn)備好一個(gè)簡短的工藝步驟描述.</p><p>　　.設(shè)備選擇. 大體上,工藝制訂者必須逐步展開利用工廠現(xiàn)有機(jī)器的計(jì)劃.另外,組件必須被購買或在新設(shè)備

44、上的投資必須被制定.</p><p>　　.工具,沖模,鑄模,夾具,量具. 工藝必須決定每個(gè)工序需要什么工具.這些工具的實(shí)際設(shè)計(jì)和制造通常通過委派工具設(shè)計(jì)部門和工具庫或者聯(lián)系專攻那種工具制造的外面廠商來完成.</p><p>　　.方法分析. 車間規(guī)劃,小工具,提升重物的提升間,甚至在一些人工操作情景中的肢體動(dòng)作也被指定.</p><p>　　.操作步驟. 工

45、作測(cè)量技術(shù)被用來為每個(gè)操作設(shè)定時(shí)間標(biāo)準(zhǔn)。</p><p>　　.切削工具和切削條件. 這些必須對(duì)加工操作通過推薦標(biāo)準(zhǔn)手冊(cè)來進(jìn)行詳細(xì)說明.</p><p><b>　　零件工藝規(guī)程制訂</b></p><p>　　對(duì)于單個(gè)零件,加工順序通過一種被稱為進(jìn)路表的表格來進(jìn)行文件證明備份. ( 不是所有的公司使用進(jìn)路表這個(gè)名字；另外的一個(gè)名字是 &qu

46、ot; 操作說明書。”)就如工程圖被用于詳細(xì)說明設(shè)計(jì)產(chǎn)品一樣,進(jìn)路表被用于詳細(xì)說明工藝計(jì)劃. 他們是類似的, 一個(gè)用于產(chǎn)品設(shè)計(jì) , 另一個(gè)用于制造。典型的進(jìn)路表 ,如 圖.21.1 中舉例,包括下列信息: (1)所有工作部分要執(zhí)行的操作都按照他們應(yīng)當(dāng)被執(zhí)行的順序列出來;(2)一個(gè)指出關(guān)于零件圖尺寸公差必須完成加工的每個(gè)操作的簡短描述;(3)用于完成這個(gè)操作的特定設(shè)備;(4)象沖模,鉆模,切削刀具,鉆夾具或夾具,和量具這樣的特定工具.一些

47、公司還包括時(shí)間設(shè)置,周期標(biāo)準(zhǔn)和其他數(shù)據(jù).他被稱為進(jìn)路表是因?yàn)楣に図樞蛞?guī)定了零件在工廠中必須遵循的路線.如表21-1中,列出了在準(zhǔn)備一個(gè)進(jìn)路表時(shí)所需要的一些指導(dǎo)方針.</p><p>　　制造單個(gè)零件的典型加工順序包括: (1) 一個(gè)基本工序,(2) 二級(jí)工序,(3) 提高物質(zhì)特性工序,和(3) 最后工序..一個(gè)基本工序決定了工件的起始造型.金屬鑄件,塑料成型,金屬精煉是基本工序中的實(shí)例. 起始造型常常必須通過改變

48、起始造型操作(或者接近于最終造型)的二級(jí)工序來精制. 二級(jí)工序習(xí)慣于和基本工序一起提供起始造型.當(dāng)砂型鑄造是基本工序,車加工通常是二級(jí)工序.當(dāng)軋鋼廠制造金屬片是基本工序,沖壓操作象沖裁和彎曲通常是二級(jí)工序.當(dāng)塑料注入成型是基本工序時(shí),二級(jí)工序通常是不必要的,因?yàn)樗拇蠖鄶?shù)幾何特征制造通過別的方式如成型制造來完成.塑料成型和其他操作的二級(jí)工序被稱為凈成型工序的并發(fā)二級(jí)工序.需要一些但并不多的二級(jí)工序的操作就是所提到的近似凈成型工序.許多有

49、印象的摸鍛件就是這一類.這類零件能夠經(jīng)常在鍛造(初級(jí)工序)階段被成型,因此減少了必要的加工(二級(jí)工序).</p><p>　　一旦模型被建立,許多零件的下一步是改良它們的機(jī)械物理性能.提高特性工序并不改變零件模型,然而,它卻能改變零件的物理特性.金屬零件的熱處理操作就是最普通的實(shí)例.類似的如玻璃通過熱處理來制造鋼化玻璃.對(duì)于大多數(shù)零件的制造來說,這些特性加強(qiáng)工序在加工工序中并不需要.</p><

50、;p>　　最后工序通常對(duì)零件(或裝配體)的表面提供一個(gè)涂層.例如電鍍,薄膜沉積技術(shù),涂漆.表面處理的目的是改善外觀,改變顏色,或者表面保護(hù)防止腐蝕和磨損等等.在很多零件中最后工序是并不需要的;例如,塑料成型就很少需要最后程序.當(dāng)必須需要最后程序,他通常是加工順序的最后一步.</p><p><b>　　裝配工藝規(guī)程制訂</b></p><p>　　一個(gè)既定產(chǎn)品的

51、典型裝配方法由以下因素決定的: (1)預(yù)期產(chǎn)品數(shù)量;(2)裝配產(chǎn)品的復(fù)雜性,例如,不同組件的數(shù)量;和(3)常用裝配工藝,例如,機(jī)械定位焊接.對(duì)于小數(shù)量產(chǎn)品,通常在人工裝配線上進(jìn)行裝配.對(duì)于大量制造的一打或這樣組件的簡單零件,要采用適當(dāng)?shù)淖詣?dòng)化裝配線.無論如何,這里有一個(gè)工作必須被完成的優(yōu)先順序.這個(gè)優(yōu)先需求經(jīng)常用一個(gè)優(yōu)先表來進(jìn)行圖表描繪.</p><p>　　裝配工藝規(guī)程制訂包括裝配指令的發(fā)展,但是更詳細(xì)地,對(duì)于