小型面條壓延機(jī)的設(shè)計(jì)【壓面條機(jī)】

購(gòu)買設(shè)計(jì)請(qǐng)充值后下載，資源目錄下的文件所見即所得，都可以點(diǎn)開預(yù)覽，資料完整，充值下載可得到資源目錄里的所有文件?！咀ⅰ浚篸wg后綴為CAD圖紙，doc,docx為WORD文檔，原稿無(wú)水印，可編輯。具體請(qǐng)見文件預(yù)覽，有不明白之處，可咨詢QQ:12401814 湖南農(nóng)業(yè)大學(xué)東方科技學(xué)院畢業(yè)論文（設(shè)計(jì)）開題論證審批表學(xué)生姓名徐貞學(xué)號(hào)200841914624年級(jí)專業(yè)及班級(jí)2008級(jí)機(jī)械設(shè)計(jì)制造及其自動(dòng)化(6)班指導(dǎo)教師及職稱高英武 教授開題時(shí)間2011年12月23日畢業(yè)論文（設(shè)計(jì)）題目小型面條壓延機(jī)的設(shè)計(jì)文獻(xiàn)綜述（選題研究意義、國(guó)內(nèi)外研究現(xiàn)狀、主要參考文獻(xiàn)等）（宋體五號(hào)，行間距單倍行距。）1、本課題綜合了機(jī)械原理、機(jī)械設(shè)計(jì)、公差配合、材料力學(xué)、畫法幾何及機(jī)械制圖等機(jī)械設(shè)計(jì)制造及其自動(dòng)化專業(yè)所開設(shè)的多個(gè)主干課程，并涉及到文獻(xiàn)檢索、專業(yè)英語(yǔ)等其它重要選修課程，因此本課題是對(duì)整個(gè)大學(xué)階段所學(xué)專業(yè)知識(shí)的一次總結(jié)與復(fù)習(xí)。在此設(shè)計(jì)過(guò)程中，應(yīng)較全面地復(fù)習(xí)專業(yè)課程的相關(guān)知識(shí)，培養(yǎng)科學(xué)的思維方式和正確的設(shè)計(jì)思想以及綜合運(yùn)用所學(xué)理論知識(shí)和專業(yè)技能、解決實(shí)際問(wèn)題的能力。此外還應(yīng)加強(qiáng)專業(yè)英語(yǔ)知識(shí)的學(xué)習(xí)，通過(guò)相關(guān)英文原版論文或書籍的翻譯，提高專業(yè)英語(yǔ)的閱讀及寫作能力。此次設(shè)計(jì)是在校期間最后一次綜合實(shí)踐，其意義在于為我們進(jìn)入機(jī)械設(shè)計(jì)行業(yè)奠定一定的理論實(shí)踐基礎(chǔ)，積累大量寶貴的設(shè)計(jì)經(jīng)驗(yàn)。2、相關(guān)研究動(dòng)態(tài)小型面條壓延機(jī)其關(guān)鍵在于壓延機(jī)，用以將面粉壓成一定厚度和一定斷面形狀。世界上很早就開始相關(guān)方面的研究。面條是我國(guó)人民所喜愛的主食品種，市場(chǎng)需求巨大，永遠(yuǎn)不愁銷路，是充滿商機(jī)的投資項(xiàng)目。而在當(dāng)代激勵(lì)競(jìng)爭(zhēng)的市場(chǎng)上，產(chǎn)品日新月異。為了提高企業(yè)的經(jīng)濟(jì)效益，就必須依據(jù)市場(chǎng)的變化情況，大力改善產(chǎn)品設(shè)計(jì)工作，迅速提高產(chǎn)品設(shè)計(jì)水平。為此，則需要根據(jù)用戶的需要，在產(chǎn)品設(shè)計(jì)過(guò)程中進(jìn)行技術(shù)經(jīng)濟(jì)分析，確定最適宜的產(chǎn)品功能，合理的技術(shù)參數(shù)，選擇適當(dāng)?shù)慕Y(jié)構(gòu)和材料，降低產(chǎn)品的成本，使得產(chǎn)品達(dá)到物美價(jià)廉。產(chǎn)品設(shè)計(jì)是集市場(chǎng).顧客.技術(shù).經(jīng)濟(jì).創(chuàng)新等重要因素為一體的綜合集成方法。只有在產(chǎn)品設(shè)計(jì)中多個(gè)角度全方位的考慮各種因素，才有助于產(chǎn)品的設(shè)計(jì)開發(fā)更加科學(xué).合理，從而提高新產(chǎn)品設(shè)計(jì)開發(fā)的成功率，降低風(fēng)險(xiǎn)，進(jìn)而幫助使用者安全合理的使用，也為增強(qiáng)企業(yè)的市場(chǎng)競(jìng)爭(zhēng)力。小型面條壓延機(jī)出面連續(xù)作業(yè)，具有高產(chǎn)高效、省時(shí)省力、操作簡(jiǎn)便等優(yōu)點(diǎn)，采用齒輪傳動(dòng)，運(yùn)轉(zhuǎn)平穩(wěn)、安全可靠；自動(dòng)輸送、自動(dòng)斷面、自動(dòng)上桿，一次成型,節(jié)省勞動(dòng)力 ；多組軋實(shí)，軋輥拉絲，喂料均勻，面板整齊 ；減速機(jī)，鏈輪鏈條傳動(dòng)，噪音低，使用壽命長(zhǎng)；操作安全，衛(wèi)生清潔。其操作特點(diǎn)，機(jī)器應(yīng)安裝在干燥、通風(fēng)的水平地面上，確保機(jī)器工作平穩(wěn)、可靠。使用前應(yīng)檢查電源電壓是否與本機(jī)使用相符；有接地符號(hào)的線芯是否可靠接地；轉(zhuǎn)向是否符合要求；按安裝好順面簸箕和接面簸箕。拌面，帶有拌粉機(jī)構(gòu)的產(chǎn)品，拌粉斗內(nèi)的攪拌器開始運(yùn)轉(zhuǎn)，拌粉均勻后打開放料器開關(guān)面粉可自動(dòng)排除。面片加工，拌好的面粉團(tuán)經(jīng)軋輥揉壓時(shí)應(yīng)由厚至薄調(diào)整軋輥間隙。切條，安裝面條刀，左右柵板設(shè)有兩條刀槽，將面條刀放入槽內(nèi)，面條刀上的齒輪與大齒輪咬合后，旋緊蝶形螺母用固定支架將面條刀固定好。切刀，將備用面片端頭用手放入轉(zhuǎn)動(dòng)中的兩輥間隙，經(jīng)再次軋制后進(jìn)入面條刀，切出面條，落入接面簸箕。操作者應(yīng)及時(shí)將切出的面條領(lǐng)出、斷開，放入晾曬架。 而本課題正是向小型面條壓延機(jī)發(fā)展的一次嘗試。但由于多方面的原因，還需進(jìn)一步研究。希望在本次課題中能夠有較大的收獲，能夠得到預(yù)想中的結(jié)果。主要參考文獻(xiàn)：1 劉朝儒,彭福蔭，高政機(jī)械制圖M北京：高等教育出版社，2008.2饒振綱.功率分流式封閉行星減速器的設(shè)計(jì)研究J.傳動(dòng)技術(shù),1996(3):30-33.3楊廷棟等.漸開線齒輪行星傳動(dòng)M.成都:成都科技大學(xué)出版社,1986.4申永勝.機(jī)械原理教程M:北京:清華大學(xué)出版社,1999.5桂乃磐,郭惠昕,羅佑新.用J特性圖計(jì)算封閉差動(dòng)輪系傳動(dòng)比的原理與方法J.湖南文理學(xué)院學(xué)報(bào),2004(5):76-77.7桂乃磐.計(jì)算行星輪系傳動(dòng)比求法的比較研究J.山西機(jī)械,2003(4):4-5.8阮忠唐.機(jī)械無(wú)級(jí)變速器設(shè)計(jì)與選用指南M.北京:化學(xué)工業(yè)出版社,1999.9日兩角宗晴著,桂乃磐譯.復(fù)合行星齒輪裝置的計(jì)算J.常德高等專科學(xué)校學(xué)報(bào),1993(2):39-46.10顏思健.漸開線齒輪行星傳動(dòng)的設(shè)計(jì)與制造M.北京:機(jī)械工業(yè)出版社,2002研究方案（研究目的、內(nèi)容、方法、預(yù)期成果、條件保障等）（宋體五號(hào)，行間距單倍行距）課題的主要內(nèi)容：壓延機(jī)的參數(shù)很多，其中主要有輥筒數(shù)目及其排列型式、輥筒的直徑和長(zhǎng)度、輥筒的調(diào)速范圍、速比和生產(chǎn)能力、壓延制品的最小厚度和厚度公差、輥筒的橫壓力和驅(qū)動(dòng)功率等。輥筒的長(zhǎng)度和直徑是指輥筒工作部分的長(zhǎng)度和直徑。這是表征壓延機(jī)規(guī)格大小的特征參數(shù)：1、輥筒長(zhǎng)度表征了可壓延制品的最大幅度。2、輥筒工作部分長(zhǎng)度和直徑的比值叫長(zhǎng)徑比。輥筒的長(zhǎng)徑比（或輥筒直徑）主要影響壓延。3、輥筒直徑與橫壓力和功率、長(zhǎng)徑比與剛度的關(guān)系 。4、輥筒長(zhǎng)度、直徑和長(zhǎng)徑比主要根據(jù)制品的生產(chǎn)工藝要求確定，即根據(jù)被加工原料的種類、壓延制品的厚度范圍和寬度范圍、輥筒的壓延速度等要求確定。 其次輥筒速度與速比，也是表征壓延機(jī)先進(jìn)程度的參數(shù)之一。輥筒速度主要根據(jù)壓延機(jī)的工藝用途和生產(chǎn)的自動(dòng)化水平來(lái)決定。輥筒速度應(yīng)能滿足壓延工藝操作的要求，即輥速應(yīng)是可調(diào)的。通過(guò)輥筒間隙時(shí)，對(duì)輥筒產(chǎn)生徑向作用力和切向作用力，徑向作用力垂直于輥面，力圖將輥筒分開，這個(gè)力就叫橫壓力，也叫分離力。輥隙中面條的橫壓力是不均勻的。此次設(shè)計(jì)應(yīng)對(duì)齒數(shù)計(jì)算、功率流分析、效率計(jì)算、強(qiáng)度計(jì)算、結(jié)構(gòu)設(shè)計(jì)。在進(jìn)行設(shè)計(jì)時(shí)，若傳動(dòng)型式、結(jié)構(gòu)組成和各齒輪的齒數(shù)選擇不當(dāng)，或輸入輸出構(gòu)件選擇不當(dāng)，將會(huì)使傳動(dòng)產(chǎn)生封閉功率，降低傳動(dòng)效率，因此應(yīng)認(rèn)真進(jìn)行效率計(jì)算，了解傳動(dòng)中功率流的方向。本設(shè)計(jì)運(yùn)用延壓機(jī)方法加以分析苗條出條率的問(wèn)題，此法可進(jìn)行運(yùn)動(dòng)分析，又可同時(shí)直接得出功率形態(tài)的種類，一舉兩得，十分方便。輪齒強(qiáng)度計(jì)算時(shí)，在已知定軸輪系和功率值的情況下，可按常規(guī)的接觸疲勞強(qiáng)度、彎曲疲勞強(qiáng)度校核，再按尖峰負(fù)荷作用強(qiáng)度校核。又由于內(nèi)嚙合傳動(dòng)強(qiáng)度遠(yuǎn)高于外嚙合，故只需對(duì)外嚙合傳動(dòng)進(jìn)行強(qiáng)度校核。最后，還應(yīng)重點(diǎn)考慮均載裝置的設(shè)計(jì)。行星傳動(dòng)裝置具有體積小、重量輕、承載能力高等優(yōu)點(diǎn)，主要是由于結(jié)構(gòu)上利用了多個(gè)行星輪分擔(dān)載荷，形成功率分流，并合理使用內(nèi)嚙合傳動(dòng)的結(jié)果，如果各行星齒輪間的載荷分配是均衡的，則行星傳動(dòng)的優(yōu)點(diǎn)可以充分發(fā)揮，否則可能增大傳動(dòng)的載荷不均衡系數(shù)，從而使運(yùn)轉(zhuǎn)噪音增大，平穩(wěn)性和可靠性降低。綜上所述，本設(shè)計(jì)論文撰寫提綱如下：1、緒論部分查閱相關(guān)資料，簡(jiǎn)要介紹目前課題研究動(dòng)態(tài)及方向2、結(jié)構(gòu)簡(jiǎn)介通過(guò)傳動(dòng)原理圖詳細(xì)說(shuō)明其運(yùn)動(dòng)原理3、壓延機(jī)的原理分析壓延機(jī)的原理，掌握用壓延機(jī)分析封閉差動(dòng)輪系傳動(dòng)比、功率流的方法。4、齒數(shù)計(jì)算參閱相關(guān)文獻(xiàn)資料，根據(jù)給定的傳動(dòng)比來(lái)分配各輪的齒數(shù)。在確定行星齒輪傳動(dòng)的各齒輪齒數(shù)時(shí)，除滿足給定的傳動(dòng)比外，還應(yīng)滿足與裝配有關(guān)的條件。5、 壓延機(jī)的原理分析壓延機(jī)的原理，掌握用壓延機(jī)分析封閉差動(dòng)輪系傳動(dòng)比、功率流的方法。6、 應(yīng)用壓延機(jī)中輥筒分析出面率問(wèn)題7、 效率、轉(zhuǎn)矩計(jì)算8、均載裝置的分析與設(shè)計(jì)分析現(xiàn)有常見的不同類型的均載裝置，綜合考慮各均載裝置的優(yōu)缺點(diǎn)，選擇最適合本設(shè)計(jì)的均載裝置9、齒輪強(qiáng)度計(jì)算時(shí)間進(jìn)程安排（各研究環(huán)節(jié)的時(shí)間安排、實(shí)施進(jìn)度、完成程度等）（宋體五號(hào)，行間距單倍行距）2011年11月 選題 2011年12月 下達(dá)任務(wù)書2011年12月 查找資料，開題報(bào)告；2012年3月至5月上旬前三周 齒數(shù)計(jì)算，功率流分析，傳動(dòng)效率計(jì)算與計(jì)算方法的比較研究 兩周時(shí)間 強(qiáng)度校核，結(jié)構(gòu)設(shè)計(jì)，均載裝置研究與設(shè)計(jì)，中期檢查兩周時(shí)間 完成裝配圖及零件圖一周時(shí)間 設(shè)計(jì)總結(jié)，全面檢查，準(zhǔn)備答辯開題論證小組意見 組長(zhǎng)簽名： 年 月 日專業(yè)委員會(huì)意見專業(yè)教研室主任簽名： 年 月 日注：此表意見欄必須由相應(yīng)責(zé)任人親筆填寫。專業(yè)名稱必須是全稱，例如“會(huì)計(jì)學(xué)專業(yè)”，班序號(hào)用阿拉伯?dāng)?shù)字“1”、“2”標(biāo)注。此表如不夠填寫，可另加頁(yè)。湖南農(nóng)業(yè)大學(xué)東方科技學(xué)院全日制普通本科生畢業(yè)設(shè)計(jì)誠(chéng)信聲明本人鄭重聲明：所呈交的本科畢業(yè)設(shè)計(jì)是本人在指導(dǎo)老師的指導(dǎo)下，進(jìn)行研究工作所取得的成果，成果不存在知識(shí)產(chǎn)權(quán)爭(zhēng)議。除文中已經(jīng)注明引用的內(nèi)容外，本論文不含任何其他個(gè)人或集體已經(jīng)發(fā)表或撰寫過(guò)的作品成果。對(duì)本文的研究做出重要貢獻(xiàn)的個(gè)人和集體在文中均作了明確的說(shuō)明并表示了謝意。同時(shí)，本論文的著作權(quán)由本人與湖南農(nóng)業(yè)大學(xué)東方科技學(xué)院、指導(dǎo)教師共同擁有。本人完全意識(shí)到本聲明的法律結(jié)果由本人承擔(dān)。 畢業(yè)設(shè)計(jì)作者簽名： 年 月 日Int J Adv Manuf Technol (2005) 25: 551559DOI 10.1007/s00170-003-1843-3ORIGINAL ARTICLES.H. Masood B. Abbas E. Shayan A. KaraAn investigation into design and manufacturing of mechanical conveyors systemsfor food processingReceived: 29 March 2003 / Accepted: 21 June 2003 / Published online: 23 June 2004 Springer-Verlag London Limited 2004Abstract This paper presents the results of a research investi-gation undertaken to develop methodologies and techniques thatwill reduce the cost and time of the design, manufacturing andassembly of mechanical conveyor systems used in the food andbeverage industry. The improved methodology for design andproduction of conveyor components is based on the minimisa-tion of materials, parts and costs, using the rules of design formanufacture and design for assembly. Results obtained on a testconveyor system verify the benets of using the improved tech-niques. The overall material cost was reduced by 19% and theoverall assembly cost was reduced by 20% compared to conven-tional methods.Keywords Assembly Cost reduction Design DFA DFM Mechanical conveyor1 IntroductionConveyor systems used in the food and beverage industry arehighly automated custom made structures consisting of a largenumber of parts and designed to carry products such as foodcartons, drink bottles and cans in fast production and assemblylines. Most of the processing and packaging of food and drink in-volve continuous operations where cartons, bottles or cans are re-quired to move at a controlled speed for lling or assembly oper-ations. Their operations require highly efcient and reliable me-chanical conveyors, which range from overhead types to oor-mounted types of chain, roller or belt driven conveyor systems.In recent years, immense pressure from clients for low costbut efcient mechanical conveyor systems has pushed con-veyor manufacturers to review their current design and assemblymethods and look at an alternative means to manufacture moreeconomical and reliable conveyors for their clients. At present,S.H. Masood (u) B. Abbas E. Shayan A. KaraIndustrial Research Institute Swinburne,Swinburne University of Technology,Hawthorn, Melbourne 3122, AustraliaE-mail: smasoodswin.edu.aumost material handling devices, both hardware and software, arehighly specialised, inexible and costly to congure, install andmaintain 1. Conveyors are xed in terms of their locations andthe conveyor belts according to their synchronised speeds, mak-ing any changeover of the conveyor system very difcult and ex-pensive. In todays radically changing industrial markets, there isa need to implement a new manufacturing strategy, a new systemoperational concept and a new system control software and hard-ware development concept, that can be applied to the design ofa new generation of open, exible material handling systems 2.Ho and Ranky 3 proposed a new modular and recongurable2D and 3D conveyor system, which encompasses an open re-congurable software architecture based on the CIM-OSA (opensystem architecture) model. It is noted that the research in thearea of improvement of conveyor systems used in beverage in-dustry is very limited. Most of the published research is directedtowards improving the operations of conveyor systems and inte-gration of system to highly sophisticated software and hardware.This paper presents a research investigation aimed at im-proving the current techniques and practices used in the de-sign, manufacturing and assembly of oor mounted type chaindriven mechanical conveyors in order to reduce the manufactur-ing lead time and cost for such conveyors. Applying the con-cept of concurrent engineering and the principles of design formanufacturing and design for assembly 4, 5, several criticalconveyor parts were investigated for their functionality, materialsuitability, strength criterion, cost and ease of assembly in theoverall conveyor system. The critical parts were modied andredesigned with new shape and geometry, and some with newmaterials. The improved design methods and the functionality ofnew conveyor parts were veried and tested on a new test con-veyor system designed, manufactured and assembled using thenew improved parts.2 Design for manufacturing and assembly (DFMA)In recent years, research in the area of design for manufacturingand assembly has become very useful for industries that are con-552sidering improving their facilities and manufacturing methodol-ogy. However, there has not been enough work done in the areaof design for conveyor components, especially related to the is-sue of increasing numbers of drawing data and re-engineeringof the process of conveyor design based on traditional methods.Emphasise standardisationUse the simplest possible operationsUse operations of known capabilityMinimise setups and interventionsUndertake engineering changes in batchesA vast amount of papers have been published that have investi-gated issues related to DFMA and applied to various methodolo-gies to achieve results that proved economical, efcient and costeffective for the companies under investigation.The main classications of DFMA knowledge can be iden-tied as (1) General guidelines, (2) Company-specic best prac-tice or (3) Process and or resource-specic constraints. Generalguidelines refer to generally applicable rules-of-thumb, relat-ing to a manufacturing domain of which the designer shouldbe aware. The following list has been compiled for DFMguidelines 6.These design guidelines should be thought of as “optimalsuggestions”. They typically will result in a high-quality, low-cost, and manufacturable design. Occasionally compromisesmust be made, of course. In these cases, if a guideline goesagainst a marketing or performance requirement, the next bestalternative should be selected 7.Company-specic best practice refers to the in-house designrules a company develops, usually over a long period of time, andwhich the designer is expected to adhere to. These design rulesare identied by the company as contributing to improved qualityand efciency by recognising the overall relationships betweenDesign for a minimum number of partsDevelop a modular designMinimise part variationsDesign parts to be multifunctionalDesign parts for multiuseDesign parts for ease of fabricationAvoid separate fastenersMaximise compliance: design for ease of assemblyMinimise handling: design for handling presentationEvaluate assembly methodsEliminate adjustmentsAvoid exible components: they are difcult to handleUse parts of known capabilityAllow for maximum intolerance of partsUse known and proven vendors and suppliersUse parts at derated values with no marginal overstressMinimise subassembliesparticular processes and design decisions. Companies use suchguidelines as part of the training given to designers of productsrequiring signicant amounts of manual assembly or mainte-nance. Note that most of the methodologies are good at eitherbeing quick and easy to start or being more formal and quanti-tative. For example, guidelines by Boothroyd and Dewhurst 8on DFA are considered as being quantitative and systematic.Whereas the DFM guidelines, which are merely rules of thumbderived from experienced professionals, are more qualitative andless formal 9.3 Conventional conveyor system designDesign and manufacturing of conveyor systems is a very com-plex and time-consuming process. As every conveyor system isa custom-made product, each project varies from every otherproject in terms of size, product and layout. The system designFig. 1. Layout of conveyor sys-tem for labelling plasic bottles553is based on client requirements and product specications. More-over, the system layout has to t in the space provided by thecompany. The process of designing a layout for a conveyor sys-tem involve revisions and could take from days to months or insome instances years. One with the minimum cost and maximumclient suitability is most likely to get approval.Figure 1 shows a schematic layout of a typical conveyorsystem installed in a production line used for labelling ofplastic bottles. Different sections of the conveyor system areidentied by specic technical names, which are commonlyused in similar industrial application. The “singlizer” sec-tion enables the product to form into one lane from multiplelanes. The “slowdown table” reduces the speed of productonce it exits from ller, labeller, etc. The “mass ow” sec-tion is used to keep up with high-speed process, e.g., ller,labeller, etc. The “transfer table” transfers the direction of prod-uct ow. The purpose of these different conveyor sections isthus to control the product ow through different processingmachines.A typical mechanical conveyor system used in food and bev-erage applications consists of over two hundred mechanical andelectrical parts depending on the size of the system. Some ofthe common but essential components that could be standard-ised and accumulated into families of the conveyor system areside frames, spacer bars, end plates, cover plates, inside bendplates, outside bend plates, bend tracks and shafts (drive, tail andslave). The size and quantity of these parts vary according to thelength of conveyor sections and number of tracks correspond-ing to the width and types of chains required. The problems andshortcomings in the current design, manufacturing and assemblyof mechanical conveyors are varied, but include:4 Areas of improvementIn order to identify the areas of cost reduction in material andlabour, a cost analysis of all main conveyor parts was conductedto estimate the percentage of cost of each part in relation to thetotal cost of all such parts. The purpose of this analysis was toidentify the critical parts, which are mainly responsible for in-creasing the cost of the conveyor and thereby investigate meansfor reducing the cost of such parts.Table 1 shows the cost analysis of a 50-section conveyor sys-tem. The analysis reveals that 12 out of 15 parts constitute 79%of the total material cost of the conveyor system, where furtherimprovements in design to reduce the cost is possible. Out ofthese, seven parts were identied as critical parts (shown by anasterisk in Table 1) constituting maximum number of compo-nents in quantity and comprising over 71% of overall materialcost. Among these, three components (leg set, side frame andsupport channel) were found to account for 50% of the totalconveyor material cost. A detailed analysis of each of these 12parts was carried out considering the principles of concurrent en-gineering, design for manufacture and design for assembly, anda new improved design was developed for each case 10. De-tails of design improvement of some selected major componentare presented below.5 Redesign of leg set assemblyIn a conveyor system, the legs are mounted on the side frame tokeep the entire conveyor system off the oor. The existing designof conveyor legs work, but they are costly to manufacture, theyOver design of some partsHigh cost of some componentsLong hours involved in assembly/maintenanceUse of non-standard partshave stability problems, and cause delays in deliveries. The delayis usually caused by some of the parts not arriving from over-seas suppliers on time. The most critical specications requiredfor the conveyor legs are:Table 1. Conveyor critical parts based on parts cost analysisProduct descriptionLeg setSide frameSupport channelBend tracksRt. roller shaftTail shaftSpacer barSupport wear stripSupport side wear stripEnd plateCover plateBend platesTorque arm bracketSlot coverInside bend plateQty68804008139391354001323939818978Material usedPlastic leg + SS tube2.5 mm SSC channel SSPlastic20 dia. SS shaft35 dia. Stainless steel50X50X6 SS40 10 mm plasticPlastic2.5 mm/SS1.6 mm S/S2.5 mm/SS6 mm S/S plateStainless steel2.5 mm/SSCost (%)20.2216.0715.0014.366.706.275.435.363.011.881.571.291.210.970.66Improvement possible (Yes/No)YesYesYesNoYesNoYesYesYesYesNoYesYesYesYesTotalCriticalparts100.00554Strength to carry conveyor loadStabilityEase of assemblyEase of exibility (for adjusting height)1 and part 3 in Fig. 2) was not rigid enough. The connectionsfor these parts are only a single 6 mm bolt. At times, when theconveyor system was carrying full product loads, it was observedthat the conveyor legs were unstable and caused mechanical vi-bration. One of the main reasons for this was due to a single boltFigure 2 indicates all the parts for the existing design ofthe conveyor leg. The indicated numbers are the part numbersdescribed in Table 2, which also shows a breakdown of cost an-alysis complete with the labour time required to assemble a com-plete set of legs. The existing leg setup consists of plastic legbrackets ordered from overseas, stainless steel leg tubes, whichare cut into specied sizes, leg tube plastic adjustments, whichare clipped onto the leg tube at the bottom as shown in Fig. 2.Lugs, which are cut in square sizes, drilled and welded to the legtube to bolt the angle cross bracing and backing plate to supportleg brackets bolts. The # of parts in Table 2 signies the numberof components in each part number and the quantity is the con-sumption of each part in the leg design. Companies have usedthis design for many years but one of the common complaintsreported by the clients was of the instability of legs.From an initial investigation, it became clear that the connec-tion between the stainless steel tube and plastic legs bracket (partFig. 2. Existing leg design assembly with partnames shown in Table 1Table 2. Cost analysis for old leg design assemblyconnection at each end of the lugs in part 3 and part 7. The sta-bility of the conveyor is considered critical matter and requiresrectication immediately to satisfy customer expectations.Considering the problems of the existing conveyor leg de-sign and the clients preferences, a new design for the conveyorleg was developed. Generally the stability and the strength ofthe legs were considered as the primary criteria for improve-ment in the new design proposal but other considerations werethe simplicity of design, minimisation of overseas parts and easeof assembly at the point of commissioning. Figure 3 shows, thenew design of the conveyors leg assembly, and Table 3 gives adescription and the cost of each part.Figure 3 shows that the new design consists of only ve mainparts for the conveyors leg compared to eight main parts in theold design. In the old design, the plastic leg bracket, the legtube plastic adjustment and the leg tube were the most expensiveitems accounting for 72% of the cost of leg assembly. In the newPart no.15, 647238Part descriptionPlastic leg bracketLeg tube plastic adjustmentLugAngle cross bracingBacking plateLeg tubeBolts# of parts2421226Qty2221226Cost$ 30.00$ 28.00$ 4.00$ 5.00$ 4.00$ 25.00$ 3.00SourceOverseasOverseasIn-houseIn-houseIn-houseIn-houseIn-houseTotal assembly cost (welding)$ 15.00In-houseTotal1917$ 114.00555Fig. 3. New design for leg assembly with partnames in Table 3Table 3. Cost analysis for new design leg assemblyPart no.13452Part descriptionStainless steel angle (50 50 3 mm)Leg plastic adjustmentCross brassingBoltsBacking plate# of parts22182Qty22142Cost$ 24.00$ 10.00$ 7.00$ 4.00$ 4.00SourceIn-houseOverseasIn-houseIn-houseIn-houseTotal assembly cost$ 10.00In-houseTotaldesign, those parts have been replaced by a stainless steel angleand a new plastic leg adjustment reducing the cost of leg assem-bly by almost 50%. Thus the total numbers of parts in the leghave been reduced from 19 to 15 and the total cost per leg setup1511Size of side frame (depth)Strength of the materialEase for assemblyEase for manufacturing$ 59.00has been reduced by $ 55 in the new design.The new conveyor leg design, when tested, was found to bemore secure and stable than the old design. The elimination ofpart number 1 and 5 from old conveyor design has made the newdesign more stable and rigid. In addition, the width of the crossbracing has also been increased with two bolts mount instead ofone in old design. This has provided the entire conveyor leg setupan additional strength.6 Redesign of the side framesThe side frame is the primary support of a conveyor systemthat provides physical strength to conveyors and almost all theparts are mounted on it. The side frame is also expected to havea rigid strength to provide support to all the loads carried onthe conveyor. It also accommodates all the associated conveyorcomponents for the assembly. The critical considerations of sideframe design are:Figure 4 shows the side frame dimension and parameters.The side frame used in existing design appears to be of rea-sonable depth in size (dimension H in Fig. 4). From the initialinvestigation, it was found that the distance between spacer barholes and return shaft (dimensions G and F in Fig. 4) could bereduced, as there was some unnecessary gap between those twocomponents. The important point to check before redening thedesign parameters was to make sure that after bringing those twocloser, the return chains would not catch the spacer bar while theconveyor is running. The model of the new side frame design wasdrawn on CAD to ensure all the specications are sound and theparts are placed in the position to check the clearances and thets. Using the principle of design for manufacturing the new sideframe design was made symmetrical so that it applies to all typesof side frames. This change is expected to reduce the size of sideframe signicantly for all sizes of chains.Table 4 shows a comparison of dimensions in the old designand the new design of side frames for the same chain type. It556Fig. 4. Side frame dimensionsTable 4. New and old side frame dimension parametersOld designChain type3.25 LF/SSSTR/LBP/MAGA31B92C71D196E65F105G211H241I136J58K85L196TAB2283621875696202232127New designChain type3.25 LF/SSSTR/LBP/MAG/TABA31B100C73D173E67F107G167H199I92J58K85L152is noted that the overall size (depth) of the conveyor has beenreduced from 241 mm to 199 mm (dimension H), which givesa saving of 42 mm of stainless steel on every side frame manu-factured. Thus, from a stainless steel sheet 1500 3000 mm, theold design parameter