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無(wú)錫太湖學(xué)院
信 機(jī) 系 機(jī)械工程及自動(dòng)化 專業(yè)
畢 業(yè) 設(shè) 計(jì)論 文 任 務(wù) 書(shū)
一、題目及專題：
1、題目 超聲清洗機(jī)吊運(yùn)機(jī)械手設(shè)計(jì)
2、專題
二、課題來(lái)源及選題依據(jù)
本課題由生產(chǎn)廠家提出，能達(dá)到實(shí)際加工要求。超聲清洗機(jī)吊運(yùn)裝置是用于物料輸送的專用設(shè)備，設(shè)備的傳動(dòng)將由機(jī)械系統(tǒng)完成，電氣控制由PLC完成。本課題既能達(dá)到鍛煉學(xué)生設(shè)計(jì)能力，且為機(jī)電綜合的設(shè)計(jì)水平，特別是機(jī)械及電控的設(shè)計(jì)制造。又能熟悉如何從圖紙到實(shí)際工作完成的整個(gè)過(guò)程，并經(jīng)實(shí)際的動(dòng)手完成真正能正常工作的設(shè)備。
3、 本設(shè)計(jì)（論文或其他）應(yīng)達(dá)到的要求：
1．達(dá)到技術(shù)指標(biāo)所規(guī)定要求，滿足實(shí)際工作需要。
2．PLC全自動(dòng)控制，要有較高的工作可靠性；安全性。
3．主機(jī)部件需作有限元應(yīng)力分析，以及相應(yīng)的運(yùn)動(dòng)學(xué)分析。
4．工作時(shí)定位準(zhǔn)確，啟停無(wú)沖擊。
5．工作時(shí)噪音小，發(fā)熱較小，工作可靠。實(shí)習(xí)地點(diǎn)：無(wú)錫。
主要技術(shù)指標(biāo)：
滿足用戶提出的書(shū)面技術(shù)要求。
工作量要求：
1．.總裝圖：機(jī)械手裝配圖0#；整機(jī)裝配圖0#。
2.主要部裝圖：設(shè)備動(dòng)作流程圖2#，電氣原理圖0#，
重要零件圖：電氣布置圖1#；。
3.重要零件的應(yīng)力應(yīng)變分析; 整機(jī)三維裝配圖，機(jī)械手三維裝配圖，動(dòng)作流程模擬動(dòng)畫(huà)仿真，PLC程序的編制
4．完整的設(shè)計(jì)及使用說(shuō)明書(shū)（電氣選型；PLC程序）。
5．必要的技術(shù)資料翻譯（8000字符）。
四、接受任務(wù)學(xué)生
機(jī)械91 班 姓名 周 劍
五、開(kāi)始及完成日期：
自2012年11月12日 至2013年5月25日
六、設(shè)計(jì)（論文）指導(dǎo)（或顧問(wèn)）：
指導(dǎo)教師 簽名
簽名
簽名
教研室主任
〔學(xué)科組組長(zhǎng)研究所所長(zhǎng)〕 簽名
系主任 簽名
2012年11月12
無(wú)錫太湖學(xué)院
畢業(yè)設(shè)計(jì)（論文）
開(kāi)題報(bào)告
題目：超聲清洗機(jī)吊運(yùn)機(jī)械手設(shè)計(jì)
信機(jī)系 機(jī)械工程及其自動(dòng)化專業(yè)
學(xué) 號(hào)： 0923048
學(xué)生姓名： 周 劍
指導(dǎo)教師： 林承德 （職稱：教 授 ）
（職稱： ）
2012年11 月
課題來(lái)源
本課題由生產(chǎn)廠家提出，能達(dá)到實(shí)際加工要求。超聲清洗機(jī)吊運(yùn)裝置是用于物料輸送的專用設(shè)備，設(shè)備的傳動(dòng)將由機(jī)械系統(tǒng)完成，電氣控制由PLC完成。本課題既能達(dá)到鍛煉學(xué)生設(shè)計(jì)能力，且為機(jī)電綜合的設(shè)計(jì)水平，特別是機(jī)械及電控的設(shè)計(jì)制造。又能熟悉如何從圖紙到實(shí)際工作完成的整個(gè)過(guò)程，并經(jīng)實(shí)際的動(dòng)手完成真正能正常工作的設(shè)備。
科學(xué)依據(jù)（包括課題的科學(xué)意義；國(guó)內(nèi)外研究概況、水平和發(fā)展趨勢(shì)；應(yīng)用前景等）
一般工業(yè)超聲波清洗機(jī)清洗包括車輛、輪船、飛機(jī)表面的清洗，一般只能去掉比較粗大的污垢；精密工業(yè)超聲波清洗機(jī)清洗包括各種產(chǎn)品加工生產(chǎn)過(guò)程中的清洗，各種材料及設(shè)備表面的清洗等，以能夠去除微小的污垢粒子為特點(diǎn)；超精密超聲波清洗機(jī)清洗包括精密工業(yè)生產(chǎn)過(guò)程中對(duì)機(jī)械零件、電子元件，光學(xué)部件等的超精密清洗，以清除極微小污垢顆粒為目的。根據(jù)超聲波清洗機(jī)清洗方法的不同，也可以分為物理超聲波清洗機(jī)清洗和化學(xué)超聲波清洗機(jī)清洗。利用力學(xué)、聲學(xué)、光學(xué)、電學(xué)、熱學(xué)的原理，依靠外來(lái)能量的作用，如機(jī)械摩擦、超聲波、負(fù)壓、高壓沖擊、紫外線、蒸汽等去除物體表面污垢的方法叫物理清洗；依靠化學(xué)反應(yīng)的作用，利用化學(xué)藥品或其它溶劑清除物體表面污垢的方法叫化學(xué)清洗，如用各種無(wú)機(jī)或有機(jī)酸去除物體表面的銹跡、水垢，用氧化劑去除物體表面的色斑，用殺菌劑、消毒劑殺滅微生物并去除霉斑等。物理清洗和化學(xué)清洗都存在著各自的優(yōu)缺點(diǎn)，又具有很好的互補(bǔ)性。在實(shí)際應(yīng)用過(guò)程中，通常都是把兩者結(jié)合起來(lái)使用，以獲得更好的超聲波清洗機(jī)清洗效果。
研究?jī)?nèi)容
1．達(dá)到技術(shù)指標(biāo)所規(guī)定要求，滿足實(shí)際工作需要。
2．PLC全自動(dòng)控制，要有較高的工作可靠性；安全性。
3．主機(jī)部件需作有限元應(yīng)力分析，以及相應(yīng)的運(yùn)動(dòng)學(xué)分析。
4．工作時(shí)定位準(zhǔn)確，啟停無(wú)沖擊。
5．工作時(shí)噪音小，發(fā)熱較小，工作可靠。實(shí)習(xí)地點(diǎn)：無(wú)錫。
主要技術(shù)指標(biāo)：
滿足用戶提出的書(shū)面技術(shù)要求。
工作量要求：
1． 總裝圖：機(jī)械手裝配圖0#；整機(jī)裝配圖0#。
2． 主要部裝圖：設(shè)備動(dòng)作流程圖2#，電氣原理圖0#，
3． 重要零件圖：電氣布置圖1#；。
4． 重要零件的應(yīng)力應(yīng)變分析; 整機(jī)三維裝配圖，機(jī)械手三維裝配圖，動(dòng)作流程 模擬動(dòng)畫(huà)仿真，PLC程序的編制
5． 完整的設(shè)計(jì)及使用說(shuō)明書(shū)（電氣選型；PLC程序） 。
擬采取的研究方法、技術(shù)路線、實(shí)驗(yàn)方案及可行性分析
本設(shè)計(jì)中主要分三個(gè)階段:
1． 零部件的設(shè)計(jì)，主要包括傳動(dòng)裝置的設(shè)計(jì)和機(jī)架的設(shè)計(jì)。
2． 電氣設(shè)計(jì)，主要包括氣動(dòng)原理圖，PLC控制的圖及流程圖。
3． 程序的調(diào)試，在三菱編程的環(huán)境下進(jìn)行模擬運(yùn)行。
因?yàn)楸驹O(shè)計(jì)已經(jīng)生產(chǎn)為實(shí)物了，而且它也已經(jīng)被廣泛的使用了，所以它的可行性是毋庸置疑的。
研究計(jì)劃及預(yù)期成果
研究計(jì)劃：
2012年11月14日-2012年12月2日：按照任務(wù)書(shū)要求查閱論文相關(guān)參考資料，填寫(xiě)畢業(yè)設(shè)計(jì)開(kāi)題報(bào)告書(shū)。
2013年1月7日-2013年1月20日：學(xué)習(xí)并翻譯一篇與畢業(yè)設(shè)計(jì)相關(guān)的英文材料。
2013年1月29日-2013年3月3日：填寫(xiě)畢業(yè)實(shí)習(xí)報(bào)告。
2013年3月4日-2013年3月10日：按照要求修改畢業(yè)設(shè)計(jì)開(kāi)題報(bào)告。
2013年3月18日-2013年3月24日：零部件的設(shè)計(jì)，主要包括傳動(dòng)裝置的設(shè)計(jì)和機(jī)架的設(shè)計(jì)。。
2013年3月25日-2013年3月31日：電氣設(shè)計(jì)，主要包括氣動(dòng)原理圖，PLC控制的圖及流程圖。
2013年4月1日-2013年4月7日：程序的調(diào)試，在三菱編程的環(huán)境下進(jìn)行模擬運(yùn)行。
2013年4月8日-2013年5月25日：畢業(yè)論文撰寫(xiě)和修改工作。
預(yù)期成果：
既能達(dá)到鍛煉學(xué)生設(shè)計(jì)能力，且為機(jī)電綜合的設(shè)計(jì)水平，特別是機(jī)械及電控的設(shè)計(jì)制造。又能熟悉如何從圖紙到實(shí)際工作完成的整個(gè)過(guò)程，并經(jīng)實(shí)際的動(dòng)手完成真正能正常工作的設(shè)備。
特色或創(chuàng)新之處
該系統(tǒng)是綜合運(yùn)用了機(jī)電一體化技術(shù)，在電控方面主要用到PLC進(jìn)行控制，PLC具有可靠性高、抗干擾能力強(qiáng)，靈活性好，編程方便等特點(diǎn)，總的系統(tǒng)使原來(lái)復(fù)雜的動(dòng)作變成相當(dāng)簡(jiǎn)單操作，電氣系統(tǒng)采用三菱PLC控制，控制電子元件均采用新材料或進(jìn)口名牌元件，經(jīng)久耐用，噪音低，系統(tǒng)的可靠性和可操作性都有所提高。該設(shè)計(jì)的最大的特點(diǎn)是密切聯(lián)系實(shí)際，可以極大的鍛煉我們的動(dòng)手能力和解決問(wèn)題的能力。
已具備的條件和尚需解決的問(wèn)題
已具備的條件：
零部件的設(shè)計(jì)，電氣方面的原理圖以及電氣接線圖都已經(jīng)達(dá)到預(yù)期的設(shè)計(jì)要求。
尚需解決的問(wèn)題：
1、 本設(shè)計(jì)的工作流程有九步，所以要九個(gè)槽體，設(shè)備本身就比較的龐大。
零件放在槽體里面都要花一次的時(shí)間清洗，所以一個(gè)流程所花的時(shí)間比較的長(zhǎng)。
指導(dǎo)教師意見(jiàn)
指導(dǎo)教師簽名：
年 月 日
教研室（學(xué)科組、研究所）意見(jiàn)
教研室主任簽名：
年 月 日
系意見(jiàn)
主管領(lǐng)導(dǎo)簽名：
年 月 日
機(jī)械手動(dòng)作流程：
前手（原始位置在進(jìn)料區(qū)上方）
A．進(jìn)料10S-前手降5S-前手退2S（鉤?。?前手升5S-前手進(jìn)10S-前手降5S（1槽酸洗開(kāi)始）-180S到-前手升5S-前手進(jìn)10S-前手降5S（2槽水洗開(kāi)始）- 20S到-前手升5S-前手進(jìn)10S-前手降5S（3槽酸洗開(kāi)始）- 30S到-前手升5S-前手進(jìn)10S-前手降5S（4槽酸洗開(kāi)始）- 30S到-前手升5S-前手進(jìn)10S-前手降5S（5槽水洗開(kāi)始）-前手進(jìn)（松開(kāi)）3S-前手升5S-前手退30S（在進(jìn)料區(qū)上方）-周而復(fù)始。
后手（原始位置在6槽上方）。
B．后手退10S-后手降5S-后手退（鉤?。?S-后手升5S-后手進(jìn)10S-后手降（6槽堿洗開(kāi)始）5S-60S到-后手升5S-后手進(jìn)10S-后手降5S（7槽水洗開(kāi)始）-30S到-后手升5S-后手進(jìn)10S-后手降（8槽防銹開(kāi)始）5S-180S到-后手升5S-后手進(jìn)10S-后手降5S（9槽防銹開(kāi)始）-30S到-后手升5S-后手進(jìn)10S-后手降5S（出料區(qū)）-后手升5S-后手退30S（在6槽上方）-周而復(fù)始。
C．出料5S-風(fēng)切泵開(kāi)；接通氣路，氣缸帶動(dòng)風(fēng)刀往復(fù)運(yùn)動(dòng)-延時(shí)30S-風(fēng)切泵停；斷開(kāi)氣路，風(fēng)刀停止-出料電機(jī)轉(zhuǎn)5S；閃光提醒工件清洗完畢。
1
英文原文
Process Planning and Concurrent Engineering
Process Planning
Process planning involves determining the most appropriate manufacturing and assembly processes and the sequence in which they should be accomplished 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 processing equipment and technological capabilities of the company of plant. Parts that cannot be made internally must be purchased from outside vendors. It should be mentioned that the choice of processes is also limited by the details of the product design. This is a point we will return to later.
Process planning is usually accomplished by manufacturing engineers. The process planner must be familiar with the particular manufacturing processes available in the factory and be able to interpret engineering drawings. Based on 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 process planning.
? .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.
? .Process and sequence.? The process planner must select which processes are required and their sequence. A brief description of processing steps must be prepared.
? .Equipment selection. ?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.
? .Tools, dies, molds, fixtures, and gags.? 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, or an outside vendor specializing in that type of tool is contacted.
??.Methods analysis.? Workplace layout, small tools, hoists for lifting heavy parts, even in some cases hand and body motions must be specified for manual operations. The industrial engineering department is usually responsible for this area.
??.Work standards.? Work measurement techniques are used to set time standards for each operation.
Cutting tools and cutting conditions.? These must be specified for machining operations, often with reference to standard handbook recommendations.
Process planning for parts
For individual parts, the processing sequence is documented on a form called a route sheet. Just as engineering 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 processing sequence to fabricate an individual part consists of: (1) a basic process, (2) secondary processes, (3) operations to enhance physical properties, and (4) finishing operations. A basic process determines the starting geometry of the work parts. Metal casting, plastic molding, and rolling of sheet metal are examples of basic processes. The starting geometry must often be refined by secondary processes, operations that transform the starting geometry (or close to final geometry). The secondary geometry processes that might be used are closely correlated to the basic process that provides the starting geometry. When sand casting is the basic processes, machining operations are generally the second processes. When a rolling mill produces sheet metal, stamping operations such as punching and bending are the secondary processes. When plastic injection molding is the basic process, secondary operations are often unnecessary, because most of the geometric features that would otherwise require machining can be created by the molding operation. Plastic molding and other operation that require no subsequent secondary processing are called net shape processes. Operations that require some but not much secondary processing (usually machining) are referred to as near net shape processes. Some impression die forgings are in this category. These parts can often be shaped in the forging operation (basic processes) so that minimal machining (secondary processing) is required.
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, they 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-enhancing operations are not required in the processing sequence.
Finally finish operations usually provide a coat on the work parts (or assembly) surface. Examples included electroplating, thin 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 parts; for example, plastic molding rarely require finishing. When finishing is required, it is usually the final step in the processing sequence.
Processing Planning for Assemblies
The type of assembly method used for a given product depends on factors such as: (1) the anticipated production 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 made 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, automated assembly systems are appropriate. In any case, there is a precedence order in which the work must be accomplished. The precedence requirements are sometimes portrayed graphically on a precedence diagram.
Process planning for assembly 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 consists 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 balance solution. As in process planning for individual components, any tools and fixtures required to accomplish an assembly task must be determined, designed, built, and the workstation arrangement must be laid out.
Make or Buy Decision
An important question that arises in process planning is whether a given part should be produced in the company’s own factory or purchased from an outside vendor, and the answer to this question is known as the make or buy decision. If the company does not possess the technological equipment or expertise in the particular manufacturing processes required to make the part, then the answer is obvious: The part must be purchased because there is no internal alternative. However, in many cases, the part could either be made internally using existing equipment, or it could be purchased externally from a vendor that process similar manufacturing capability.
In our discussion of the make or buy decision, it should be recognized at the outset that nearly all manufactures buy their raw materials from supplies. A machine shop purchases its starting bar stock from a metals distributor and its sand castings from a foundry. A plastic molding plant buys its molding compound from a chemical company. A stamping press factory purchases sheet metal either fro a distributor or direct from a rolling mill. Very few companies are vertically integrated in their production operations all the way from raw materials, it seems reasonable to consider purchasing at least some of the parts that would otherwise be produced in its own plant. It is probably appropriate to ask the make or buy question for every component that is used by the company.
There are a number of factors that enter into the make or buy decision. One would think that cost is the most important factor in determining whether to produce the part or purchase it. If an outside vendor is more proficient than the company’s own plant in themanufacturing processes used to make the part, then the internal production cost is likely to be greater than the purchase price even after the vendor has included a profit. However, if the decision to purchase results in idle equipment and labor in the company’s own plant, then the apparent advantage of purchasing the part may be lost. Consider the following example make or Buy Decision.
The quoted price for a certain part is $20.00 per unit for 100 units. The part can be produced in the company’s own plant for $28.00. The components of making the part are as follows:
? Unit raw material cost = $8.00 per unit
??????????????????? Direct labor cost =6.00 per unit
??????????????????? Labor overhead at 150%=9.00 per unit
??????????????????? Equipment fixed cost =5.00 per unit
????????????????? ________________________________
?????? ??????????????????????Total =28.00 per unit
Should the component by bought or made in-house?
Solution: Although the vendor’s quote seems to favor a buy decision, let us consider the possible impact on plant operations if the quote is accepted. Equipment fixed cost of $5.00 is an allocated cost based on investment that was already made. If the equipment designed for this job becomes unutilized because of a decision to purchase the part, then the fixed cost continues even if the equipment stands idle. In the same way, the labor overhead cost of $9.00 consists of factory space, utility, and labor costs that remain even if the part is purchased. By this reasoning, a buy decision is not a good decision because it might be cost the company as much as $20.00+$5.0+$9.00=$34.00 per unit if it results in idle time on the machine that would have been used to produce the part. On the other hand, if the equipment in question can be used for the production of other parts for which the in-house costs are less than the corresponding outside quotes, then a buy decision is a good decision.
Make or buy decision are not often as straightforward as in this example. A trend in recent years, especially in the automobile industry, is for companies to stress the importance of building close relationships with parts suppliers. We turn to this issue in our later discussion of concurrent engineering.
Computer-aided Process Planning
There is much interest by manufacturing firms in automating the task of process planning using computer-aided process planning (CAPP) systems. The shop-trained people who are familiar with the details of machining and other processes are gradually retiring, and these people will be available in the future to do process planning. An alternative way of accomplishing this function is needed, and CAPP systems are providing this alternative. CAPP is usually considered to be part of computer-aided manufacturing (CAM). However, this tends to imply that CAM is a stand-along system. In fact, a synergy results when CAM is combined with computer-aided design to create a CAD/CAM system. In such a system, CAPP becomes the direct connection between design and manufacturing. The benefits derived from computer-automated process planning include the following:
??.Process rationalization and standardization.? Automated process planning leads to more logical and consistent process plans than when process is done completely manually. Standard plans tend to result in lower manufacturing costs and higher product quality.
? .Increased productivity of process planner. ?The systematic approach and the availability of standard process plans in the data files permit more work to be accomplished by the process planners.
??.Reduced lead time for process planning. ?Process planner working with a CAPP system can provide route sheets in a shorter lead time compared to manual preparation.
? .Improved legibility. ?Computer-prepared rout sheets are neater and easier to read than manually prepared route sheets.
? .Incorporation of other application programs. ?The CAPP program can be interfaced with other application programs, such as cost estimating and work standards.
Computer-aided process planning systems are designed around two approaches. These approaches are called: (1) retrieval CAPP systems and (2) generative CAPP systems .Some CAPP systems combine the two approaches in what is known as semi-generative CAPP.
Concurrent Engineering and Design for Manufacturing
Concurrent engineering refers to an approach used in product development in which the functions of design engineering, manufacturing engineering, and other functions are integrated to reduce the elapsed time required to bring a new product to market. Also called simultaneous engineering, it might be thought of as the organizational counterpart to CAD/CAM technology. In the traditional approach to launching a new product, the two functions of design engineering and manufacturing engineering tend to be separated and sequential, as illustrated in Fig.(1).(a).The product design department develops the new design, sometimes without much consideration given to the manufacturing capabilities of the company, There is little opportunity for manufacturing engineers to offer advice on how the design might be alerted to make it more manufacturability. It is as if a wall exits between design and manufacturing. When the design engineering department completes the design, it tosses the drawings and specifications over the wall, and only then does process planning begin.
Fig.(1). Comparison: (a) traditional product development cycle and (b) product development using concurrent engineering
By contrast, in a company that practices concurrent engineering, the manufacturing engineering department becomes involved in the product development cycle early on, providing advice on how the product and its components can be designed to facilitate manufacture and assembly. It also proceeds with early stages of manufacturing planning for the product. This concurrent engineering approach is pictured in Fig.(1).(b). In addition to manufacturing engineering, other function are also involved in the product development cycle, such as quality engineering, the manufacturing departments, field service, vendors supplying critical components, and in some cases the customer who will use the product. All if these functions can make contributions during product development to improve not only the new product’s function and performance, but also its produceability, inspectability, testability, serviceability, and maintainability. Through early involvement, as opposed to reviewing the final product design after it is too late to conveniently make any changes in the design, the duration of the product development cycle is substantially reduced.
Concurrent engineering includes several elements: (1) design for several manufacturing and assembly, (2) design for quality, (3) design for cost, and (4) design for life cycle. In addition, certain enabling technologies such as rapid prototyping, virtual prototyping, and organizational changes are required to facilitate the concurrent engineering approach in a company.
Design for Manufacturing and Assembly
It has been estimated that about 70% of the life cycle cost of a product is determined by basic decisions made during product design. These design decisions include the material of each part, part geometry, tolerances, surface finish, how parts are organized into subassemblies, and the assembly methods to be used. Once these decisions are made, the ability to reduce the manufacturing cost of the product is limited. For example, if the product designer decides that apart is to be made of an aluminum sand casting but which processes features that can be achieved only by machining(such as threaded holes and close tolerances), the manufacturing engineer has no alternative expect to plan a process sequence that starts with sand casting followed by the sequence of machining operations needed to achieve the specified features .In this example, a better decision might be to use a plastic molded part that can be made in a single step. It is important for the manufacturing engineer to be given the opportunity to advice the design engineer as the product design is evolving, to favorably influence the manufacturability of the product.
Term used to describe such attempts to favorably influence the manufacturability of a new product are design for manufacturing (DFM) and design for assembly(DFA). Of course, DFM and DFA are inextricably linked, so let us use the term design for manufacturing and assembly (DFM/A). Design for manufacturing and assembly involves the systematic consideration of manufacturability and assimilability in the development of a new product design. This includes: (1) organizational changes and (2) design principle and guidelines.
.Organizational Changes in DFM/A. ?Effective implementation of DFM/A involves making changes in a company’s organization structure, either formally or informally, so that closer interaction and better communication occurs between design and manufacturing personnel. This can be accomplished in several ways: (1)by creating project teams consisting of product designers, manufacturing engineers, and other specialties (e.g. quality engineers, material scientists) to develop the new product design; (2) by requiring design engineers to spend some career time in manufacturing to witness first-hand how manufacturability and assembility are impacted by a product’s design; and (3)by assigning manufacturing engineers to the product design department on either a temporary or full-time basis to serve as reducibility consultants.
Process Planning and Concurrent Engineering
T. Ramayah and Noraini Ismail
ABSTRACT
The product design is the plan for the product and its components and subassemblies. To convert the product design into a physical 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 of processing and assembly steps that must be accomplished to make the product. In the present chapter, we examine processing planning and several related topics.
Process Planning
Process planning involves determining the most appropriate manufacturing and assembly processes and the sequence in which they should be accomplished 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 processing equipment and technological capabilities of the company of plant. Parts that cannot be made internally must be purchased from outside vendors. It should be mentioned that the choice of processes is also limited by the details of the product design. This is a point we will return to later.
Process planning is usually accomplished by manufacturing engineers. The process planner must be familiar with the particular manufacturing processes available in the factory and be able to interpret engineering drawings. Based on 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 process planning.
? .Interpretation of design drawings.? The part of product design must be analyzed