炒栗子機(jī)設(shè)計(jì)【炒板栗機(jī)】

炒栗子機(jī)設(shè)計(jì)【炒板栗機(jī)】,炒板栗機(jī),炒栗子機(jī)設(shè)計(jì)【炒板栗機(jī)】,栗子,設(shè)計(jì),板栗 Manuf智力J備有工藝(2005):551-559 25.10.1007 / s00170-003-1843-3 Masood?b?阿巴斯懸Shayan?a?e卡拉調(diào)查設(shè)計(jì)和制造機(jī)械輸送系統(tǒng)，有食品加工。 2003年3月29日收到:2003年6月21日/接受:6月23日/發(fā)表在線(xiàn):2004年，斯普林格出版社倫敦有限ó2004年 摘要：本文章介紹了開(kāi)發(fā)方法和技術(shù)進(jìn)行將降低成本和時(shí)間的設(shè)計(jì)、制造和裝配的機(jī)械輸送系統(tǒng)的研究的結(jié)果，應(yīng)用于食品和食品飲料行業(yè)。改進(jìn)后的方法來(lái)設(shè)計(jì)和生產(chǎn)的自動(dòng)調(diào)節(jié)式氣力輸送的組件是基于新的材料、零件、成本、使用規(guī)則的設(shè)計(jì)制造和面向裝配的設(shè)計(jì)。結(jié)果在一個(gè)測(cè)試輸送系統(tǒng)驗(yàn)證的好處——通過(guò)采用改進(jìn)的技術(shù)。整體材料成本和傳統(tǒng)的方法相比降低了19%，整體裝配成本相比,降低了20%。 關(guān)鍵字：裝配.DFA?DFM.設(shè)計(jì)，機(jī)械輸送。 1介紹 輸送系統(tǒng)應(yīng)用于食品和飲料行業(yè)高度自動(dòng)化的定制結(jié)構(gòu)組成的一個(gè)大型零件的數(shù)量和用來(lái)攜帶產(chǎn)品,如食物紙箱裝,喝的瓶子和罐子在快速生產(chǎn)和組裝線(xiàn)。大部分的處理和包裝的食品和飲料-在紙箱、持續(xù)經(jīng)營(yíng)再保險(xiǎn)——瓶或罐等。在一個(gè)被控制quired移動(dòng)速度,對(duì)充填或者裝配墨粉壽命結(jié)束- 成為。他們的操作需要高效、可靠的我-傳送帶運(yùn)輸,操作時(shí),范圍從高架地板-類(lèi)型的安裝類(lèi)型的連鎖店,或者帶式輸送機(jī)滾筒驅(qū)動(dòng)系統(tǒng)。近年來(lái),極大的壓力來(lái)自客戶(hù)低成本但高效的機(jī)械輸送系統(tǒng)使得制造商重新檢查他們的當(dāng)前的設(shè)計(jì)和組裝等看看另一種方法和手段來(lái)制造更多經(jīng)濟(jì)、可靠的輸送帶,為他們的客戶(hù)帶來(lái)方便，目前,懸Masood(u)?b?a?e Shayan阿巴斯卡拉工業(yè)研究所一本史文朋, 一本史文朋理工大學(xué),墨爾本,澳大利亞3122山楂, 電子郵件：smasood@swin.edu.au: 改進(jìn)后的新零件大多數(shù)物料搬運(yùn)設(shè)備,硬件和軟件兩個(gè)方面,都是高度專(zhuān)業(yè)化,呆板的和昂貴的配置、安裝維持[1]。輸送帶,被固定在以他們的位置和根據(jù)他們的同步輸送帶速度,任何轉(zhuǎn)換的輸送系統(tǒng)非常困難和前期陷入沉思。在今天的從根本上改變工業(yè)市場(chǎng),有一個(gè)需要執(zhí)行一種新的制造策略,一個(gè)新的系統(tǒng)經(jīng)營(yíng)理念,并提出了一種新的系統(tǒng)控制軟件和硬-陶瓷的發(fā)展理念,可應(yīng)用于設(shè)計(jì)的新一代的開(kāi)放、靈活物料搬運(yùn)系統(tǒng)[2]。何鴻燊和Ranky[3]模型,提出了一種新的模塊化可重構(gòu)二維和三維的輸送系統(tǒng),包括一個(gè)開(kāi)放的稀土-可配置的軟件體系結(jié)構(gòu)的基礎(chǔ)上,CIM-OSA(打開(kāi) 系統(tǒng)架構(gòu))模型。指出研究地區(qū)輸送系統(tǒng)的改進(jìn)、完善和提高,用于飲料-焦化是非常有限的。大部分的發(fā)表的研究論文是指揮 用于改善輸送系統(tǒng)的操作和交互的系統(tǒng)非常復(fù)雜的軟件和硬件。本文提出一種研究調(diào)查，實(shí)踐證明,使用當(dāng)前技術(shù)標(biāo)志、制造和裝配型鏈?zhǔn)降牡匕迳? 驅(qū)動(dòng)機(jī)械輸送設(shè)備,以減少制造這樣的運(yùn)輸機(jī)的時(shí)間和成本。應(yīng)用了并行工程的設(shè)計(jì)和實(shí)施的基本原則 面向裝配的設(shè)計(jì)制造和[4、5],幾個(gè)關(guān)鍵研究了輸送機(jī)零部件都是為他們的功能、材料適宜性、強(qiáng)度準(zhǔn)則、成本和簡(jiǎn)化了安裝的 整體輸送系統(tǒng)。這個(gè)關(guān)鍵零部件進(jìn)行了改性用新的形狀和幾何位置重新設(shè)計(jì),以及一些新材料。改進(jìn)后的設(shè)計(jì)方法和功能 驗(yàn)證了新型平零件上測(cè)試了一種新測(cè)試,系統(tǒng)設(shè)計(jì)、制造和組裝過(guò)程中使用。 設(shè)計(jì)制造和裝配DFMA) 近年來(lái),研究在該地區(qū)的可制造性設(shè)計(jì)和裝配已成為非常有用,因?yàn)樗麄冋诳紤]提高工業(yè)設(shè)施和生產(chǎn)。然而,沒(méi)有足夠的工作完成后,在該地區(qū)輸送機(jī)的設(shè)計(jì),特別是相關(guān)的組件是使得越來(lái)越多的圖紙數(shù)據(jù)與重組。輸送過(guò)程的設(shè)計(jì)基于傳統(tǒng)的方法。 大量的文章發(fā)表,investi -DFMA封閉的相關(guān)問(wèn)題,并將其應(yīng)用于各種methodolo -要達(dá)成目標(biāo),使經(jīng)濟(jì)、高效和成本證明 有效的對(duì)這些公司正在調(diào)查之中。 主要的分類(lèi)知識(shí)就可以影響DFMA - 問(wèn)題的一般準(zhǔn)則為(1)、(2)特定公司的最佳 (3)進(jìn)行resource-specific過(guò)程和或約束。一般指通常適用rules-of-thumb指南,到制造領(lǐng)域的設(shè)計(jì)師應(yīng)該注意。下面的列表整理了DFM指南[6]。 ?設(shè)計(jì)最小數(shù)目的部分 ?開(kāi)發(fā)一種模塊化設(shè)計(jì) ?最小化部分變化 多功能?設(shè)計(jì)部件 multiuse?設(shè)計(jì)零件 為便于設(shè)計(jì)部分的0.9%的制造 ?避免單獨(dú)緊固件 靈活性:?最大化設(shè)計(jì)為便于裝配 處理:設(shè)計(jì)?最小化處理的簡(jiǎn)報(bào) ?評(píng)估的裝配方法 ?消除調(diào)整 避免靈活的組件?:他們很難對(duì)付 ?使用零件已知的能力 偏執(zhí)?允許的最高部分 使用已知的和證明?零售商和供應(yīng)商 在derated?使用零件析出大量的價(jià)值觀(guān)與沒(méi)有邊際 ?最小化組件 ?強(qiáng)調(diào)標(biāo)準(zhǔn)化 ?使用盡可能簡(jiǎn)單的操作 使用已知的能力?操作 啟動(dòng)和干預(yù)措施。?最小化 承接的工程更改?批量生產(chǎn) 這些設(shè)計(jì)指導(dǎo)方針應(yīng)該被認(rèn)為是“最優(yōu)的建議”。他們通常會(huì)導(dǎo)致高質(zhì)量、低-成本,地設(shè)計(jì)。偶爾的妥協(xié)必須被做,當(dāng)然。在這些情況下,如果一個(gè)指導(dǎo)方針,走過(guò)去了對(duì)市場(chǎng)營(yíng)銷(xiāo)或性能要求,下一個(gè)最好的選擇應(yīng)選擇[7]。 它是指特定公司的最佳實(shí)踐的內(nèi)部設(shè)計(jì)公司開(kāi)發(fā)的條例,通常是在很長(zhǎng)一段時(shí)間,和設(shè)計(jì)師是沿襲。這些設(shè)計(jì)規(guī)則是確定的公司等導(dǎo)致質(zhì)量得以改善嗎通過(guò)識(shí)別和效率的總體關(guān)系特定的過(guò)程和設(shè)計(jì)決策。公司使用這樣的培訓(xùn)指導(dǎo)方針的一部分給設(shè)計(jì)師的產(chǎn)品需要大量的手工裝配或-維護(hù)。值得注意的是,大部分的方法論擅長(zhǎng)任選一種被快速和容易的開(kāi)始,或者是被更正式的。例如,指導(dǎo)方針,布斯羅伊德Dewhurst[8],在DFA被視為定量和系統(tǒng)的。 而DFM指導(dǎo)方針,這僅僅是法則經(jīng)驗(yàn)豐富的專(zhuān)業(yè)人員,是源自于一些定性和不那么正式的[9]。 3．傳統(tǒng)的輸送系統(tǒng)的設(shè)計(jì) 輸送系統(tǒng)的設(shè)計(jì)和制造是一個(gè)非常復(fù)雜和費(fèi)時(shí)的過(guò)程。像每個(gè)輸送系統(tǒng)一個(gè)定做的產(chǎn)品,每個(gè)項(xiàng)目不同于其他的項(xiàng)目在規(guī)模、產(chǎn)品和布局。該系統(tǒng)設(shè)計(jì)是基于客戶(hù)需求,產(chǎn)品的規(guī)格要求。該系統(tǒng)布局必須適合在空間所提供的公司。這個(gè)過(guò)程的設(shè)計(jì)規(guī)劃系統(tǒng)-輸送機(jī)瞬變電磁法(tem)涉及修改以及可能要花上數(shù)天到數(shù)月不等或某些情況下十年。一個(gè)以最低的成本和最大。 最有可能的客戶(hù)適用性得到認(rèn)可。圖1顯示一個(gè)圖解的布局對(duì)一典型輸送機(jī)系統(tǒng)安裝在生產(chǎn)線(xiàn)用于標(biāo)簽塑料瓶。輸送機(jī)系統(tǒng)的不同地區(qū)特殊的技術(shù)鑒定的名字,一般運(yùn)用于類(lèi)似的工業(yè)應(yīng)用。美國(guó)證券交易委員會(huì)(sec)的“singlizer”-使產(chǎn)品的聲譽(yù)形成一條車(chē)道從多個(gè)車(chē)道?！敖?jīng)濟(jì)放緩的速度表“降低產(chǎn)品一旦它的出口,labeller填料等。美國(guó)證券交易委員會(huì)(sec)的“大規(guī)模流動(dòng)”-興是用來(lái)跟上高速過(guò)程,例如,填料,labeller等?！稗D(zhuǎn)會(huì)表”的方向發(fā)展,促進(jìn)轉(zhuǎn)移-流動(dòng)。這些不同的目的是輸送機(jī)部分因此為了控制產(chǎn)品,通過(guò)不同的處理流程。一個(gè)典型的機(jī)械輸送系統(tǒng)用于食品應(yīng)用包括了兩百機(jī)械根據(jù)大小電器部件的系統(tǒng)。一些常見(jiàn)的但又極為重要的組件,可能是標(biāo)準(zhǔn)和積累了家族的輸送系統(tǒng)。側(cè)架、間隔臂的酒吧,最后板、覆蓋板、內(nèi)彎板、外板、彎曲的軌道和井(開(kāi)車(chē),尾巴和奴隸)。大小和數(shù)量的變化來(lái)表明自己的這些部分的長(zhǎng)度的自動(dòng)調(diào)節(jié)式氣力輸送的對(duì)應(yīng)部分的內(nèi)容和數(shù)量的軌跡-ing的寬度和類(lèi)型的鏈所要求的。存在的問(wèn)題及在當(dāng)前的設(shè)計(jì)缺陷、制造和裝配機(jī)械輸送設(shè)備多樣化、包括: ?在設(shè)計(jì)對(duì)部分 ?高成本的一些組件 ?長(zhǎng)時(shí)間參與總裝/維修 ?使用非標(biāo)零件 圖1 4．部分的改進(jìn) 為了識(shí)別領(lǐng)域的材料、降低成本勞動(dòng)的成本分析的主要輸送部件進(jìn)行了研究估計(jì)成本的百分比各部分的關(guān)系所有這類(lèi)零件的總成本。這個(gè)分析的目的是為了識(shí)別關(guān)鍵零部件,主要負(fù)責(zé)在-壓痕的成本,從而探討輸送方式對(duì)于降低成本的部分。 表1顯示了一個(gè)50-section輸送機(jī)的成本分析系統(tǒng)-瞬變電磁法(tem)。通過(guò)分析可知,有12個(gè)零件組成的15達(dá)79%總材料成本的輸送系統(tǒng),在那里的進(jìn)一步研究的重點(diǎn)改進(jìn)設(shè)計(jì),降低成本是可能的。從這些,七個(gè)部分,分別鑒定為關(guān)鍵的部位(顯示的 星號(hào)符號(hào)在表1)構(gòu)成最大數(shù)量的成分-達(dá)71%的數(shù)量,并包括在整體上的資料成本。在這些人之中,三種成分(腿套,側(cè)架和支持渠道)被發(fā)現(xiàn)占總數(shù)的50%輸送機(jī)材料成本。詳細(xì)分析了每一種12考慮到零件的原則進(jìn)行并行en -工程、設(shè)計(jì)制造和面向裝配的設(shè)計(jì),和研制了一種新的改進(jìn)設(shè)計(jì),每宗[10]。德-改進(jìn)設(shè)計(jì)的尾巴的一些選定的主要部件 5.腿套附件的重新設(shè)計(jì) 在一個(gè)輸送系統(tǒng),腿是安裝在側(cè)架保持整個(gè)輸送系統(tǒng)在了地板上。現(xiàn)有的設(shè)計(jì)工作的自動(dòng)調(diào)節(jié)式氣力輸送的腿,但是花費(fèi)也很昂貴的制造、他們有穩(wěn)定的問(wèn)題,并會(huì)造成延誤發(fā)貨。延遲 通常是造成這些部分不到位從超過(guò)- 供應(yīng)商準(zhǔn)時(shí)。最關(guān)鍵的規(guī)格要求為輸送機(jī)是: 帶式輸送機(jī)?強(qiáng)度負(fù)荷 ?穩(wěn)定性 ?簡(jiǎn)化了安裝 安逸的靈活性(?調(diào)整高)。 圖2顯示的所有部件的使用現(xiàn)有的設(shè)計(jì)輸送機(jī)的腿。指定的密碼是零件編號(hào)表2中所描述的,體現(xiàn)了一種——的一個(gè)故障成本。 完整的勞動(dòng)時(shí)間要求組裝系統(tǒng)性的腿?，F(xiàn)有的腿設(shè)置由塑料腿括號(hào)內(nèi)的命令來(lái)自海外,不銹鋼管,腿 切成指定的尺寸,腿管子塑料的調(diào)整,是哪一種管夾到腿是在底部,如圖2。凸耳,切成大小、鉆孔、焊接而成廣場(chǎng)到腿 管螺栓角度拉條和背襯板,以支持腿支架螺栓。#各部分的表2意味著這個(gè)號(hào)碼在每個(gè)部分元件的數(shù)量和質(zhì)量是特殊的。 腿各部分的設(shè)計(jì)。公司利用這個(gè)設(shè)計(jì)為許多年,但一個(gè)常見(jiàn)的投訴。據(jù)報(bào)導(dǎo),客戶(hù)是不穩(wěn)定的腳。從最初的調(diào)查,就變得很明顯就是不銹鋼管的聲譽(yù)之間和塑料腿支架(部分 在圖1和第3部分。2)沒(méi)有剛性足夠了。連接這些零件是唯一一個(gè)6毫米螺栓。有時(shí),當(dāng)輸送系統(tǒng)正載著滿(mǎn)載荷、觀(guān)察發(fā)現(xiàn)產(chǎn)品 輸送機(jī)的腿是不穩(wěn)定的,并引起了機(jī)械震動(dòng)。其中最主要的原因是由于一個(gè)單一的螺栓連接兩端的凸耳在第三部分和部分的——輸送機(jī)可靠性具有重要物質(zhì)和要求。 為了滿(mǎn)足顧客的期望立即改正?？紤]到存在的問(wèn)題——輸送機(jī)腿德標(biāo)志和客戶(hù)的喜好,一個(gè)新設(shè)計(jì)的輸送機(jī)腿被發(fā)展。一般的強(qiáng)度和穩(wěn)定性腿被認(rèn)為是主要的標(biāo)準(zhǔn)。 在新的設(shè)計(jì)方案的觀(guān)點(diǎn),但其他的考慮簡(jiǎn)單的計(jì),海外部分的安逸裝配環(huán)節(jié)的調(diào)試。圖3顯示,新設(shè)計(jì)的輸送機(jī)的腿總成,和表3給出了描述和造價(jià)的每一部分。 圖3顯示,新設(shè)計(jì)僅由五個(gè)主要的各部位為輸送機(jī)的腿比八種主要的部件舊的設(shè)計(jì)。在舊的設(shè)計(jì)、塑料腿支架,腿塑料調(diào)節(jié)和腿管子管是最貴的項(xiàng)目成本核算的72%的腿總成。 表1。輸送機(jī)關(guān)鍵零部件,基于部件成本分析 產(chǎn)品說(shuō)明 腿*設(shè)置 *側(cè)架 支持渠道* 彎曲軌跡 *Rt.滾子軸 尾軸 間隔條* 支持*穿帶 支持一端穿條* 終板 蓋板 彎板 轉(zhuǎn)矩臂支架 槽蓋 彎板內(nèi) 總 關(guān)鍵零部件 數(shù)量 68 80 400 8 139 39 135 400 132 39 39 8 18 97 8 材料應(yīng)用 塑料腿+ SS管 2 5.m m SS C 信道SS 塑料 20直徑的S軸 35直徑不銹鋼 50X50X6 SS 40×10毫米塑料 塑料 2 5.m m / SS 1 6.m m S / S 2 5.m m / SS 6毫米的飛船空間站板 不銹鋼2 5.m m / SS 花費(fèi)(%) 20.22 16.07 15.00 14.36 6.70 6.27 5.43 5.36 3.01 1.88 1.57 1.29 1.21 0.97 0.66 100.00 改進(jìn)的可能 是的 是的 是的 沒(méi)有 是的 沒(méi)有 是的 是的 是的 是的 沒(méi)有 是的 是的 是的 是的 是的 *表2。成本分析對(duì)老腿設(shè)計(jì)組裝 部分描述。 1 塑料腿支架 5 腿管子塑料調(diào)整 6 凸 4 角度拉條 7 背襯板 2 腿管 3 螺栓 8 總裝配成本(焊接) 圖2 圖3 表3。成本分析對(duì)新設(shè)計(jì)的腿總成 （部分描述） 1 不銹鋼角(50×50×3毫米) 3 腿塑料調(diào)整 4 交叉brassing 5 螺栓 2 背襯板 結(jié)果,那些部分都已經(jīng)被一種不銹鋼角的影響并提出了一種新的塑料腿調(diào)整降低生產(chǎn)成本的腿assem -bly由接近50%。因此零件的總數(shù)量的腿從19日已減少到15和總成本為每回合的設(shè)置 減少了55美元的新設(shè)計(jì)。新輸送機(jī)腿設(shè)計(jì)、測(cè)試時(shí),被發(fā)現(xiàn) 更為安全、穩(wěn)定的比舊的設(shè)計(jì)。消除零件號(hào)1個(gè)月和5從老式輸送機(jī)設(shè)計(jì)作出了新的設(shè)計(jì)更加穩(wěn)定和剛性的。此外,寬度,釘在十字架上支撐也有提高,而不是兩個(gè)螺栓的山一個(gè)在舊的設(shè)計(jì)。這樣就提供了整個(gè)輸送機(jī)腿的設(shè)置額外的力量。 6側(cè)架的重塑 邊框架是首要支持輸送系統(tǒng)提供體力輸送機(jī)及幾乎所有的 零件安裝在它。側(cè)架的預(yù)計(jì)也會(huì)有一個(gè)剛性的力量來(lái)提供必要的支持給所有的荷載進(jìn)行了輸送機(jī)。它也可適應(yīng)所有相關(guān)的輸送機(jī) 組件的裝配。關(guān)鍵的考慮的一面框架設(shè)計(jì)是: 側(cè)架的大小(?深度) ?強(qiáng)度的材料 ?易于裝配 ?易于制造 圖4顯示了側(cè)架尺寸和參數(shù)。 側(cè)架的使用,在現(xiàn)有的設(shè)計(jì)深度尺寸(尺寸H在圖4)調(diào)查時(shí),發(fā)現(xiàn)之間的距離間隔的酒吧，軸(孔尺寸和回報(bào)G和F,如圖4)降低的時(shí)候,就像有了一些不必要的兩個(gè)人之間的距離。更為重要的一點(diǎn),定義之前先檢查一下設(shè)計(jì)參數(shù),以確保帶來(lái)另外兩份關(guān)系更加密切,返回鏈不會(huì)趕上間隔條而輸送機(jī)在運(yùn)行。該模型的新球隊(duì)的框架設(shè)計(jì)畫(huà)在計(jì)算機(jī)輔助設(shè)計(jì)(CAD),以確保所有的規(guī)格是聲音部分是放置在位置和檢查的間隙很適合。通過(guò)這一原則的可制造性設(shè)計(jì)的新球隊(duì)的框架設(shè)計(jì)是對(duì)稱(chēng)的,以便它適用于所有類(lèi)型 側(cè)架的。這個(gè)變化將減小尺寸的一邊所有通徑的框架顯著鏈。 表4顯示的維度上的比較舊的設(shè)計(jì)和新設(shè)計(jì)的側(cè)架為同一鏈類(lèi)型。 圖4 表4。新的和舊的側(cè)架尺寸參數(shù) 它指出整體規(guī)模(深度)的輸送機(jī)有什么期望減少241 mm 199毫米(尺寸H),節(jié)約了42毫米不銹鋼在每側(cè)架馬努-factured。因此,從一個(gè)不銹鋼薄板×毫米,1500 3000股老設(shè)計(jì)參數(shù)只允許六3米長(zhǎng)的側(cè)架但隨著新的設(shè)計(jì)參數(shù),現(xiàn)在它是可能的生產(chǎn)7側(cè)架3米長(zhǎng)從同樣的表大小。用于的資料數(shù)量也是再保險(xiǎn)——側(cè)架認(rèn)為為更深入的研究。據(jù)估計(jì),約55%總成本的輸送系統(tǒng)都花在材料。 目前的資料用于側(cè)架是2.5毫米厚污點(diǎn)-304鋼的等級(jí)食物少。目前,還有其他的材料市場(chǎng)上可以買(mǎi)到的厚度,可以選擇作為一個(gè)選項(xiàng)。為此,一位撓度分析進(jìn)行了預(yù)測(cè),如果有任何其他類(lèi)型的資料西裝能夠取代現(xiàn)有的資料,這樣它才不會(huì)沒(méi)有通過(guò)它的 強(qiáng)度標(biāo)準(zhǔn)。分析6.1撓度側(cè)架圖5給出了確定的實(shí)驗(yàn)系統(tǒng)實(shí)踐新球隊(duì)的框架下,在X,Y方向不同加載條件。隨著新的設(shè)計(jì)參數(shù)的一組側(cè)架的生產(chǎn)調(diào)查撓度等1 6.m米厚的不銹鋼側(cè)架。一段側(cè)架螺栓與間隔條和回歸測(cè)試-軸是組裝做這個(gè)實(shí)驗(yàn)。獲得的結(jié)果撓度運(yùn)用可變荷載側(cè)架的一個(gè)區(qū)段通過(guò)一個(gè)液壓。顯示在圖5,撓度表 放置在垂直(Y)和橫向(X)軸來(lái)測(cè)量嗎任何閱讀上觀(guān)察到的側(cè)架。應(yīng)用的負(fù)荷是通過(guò)對(duì)側(cè)架的液壓機(jī)向下方向。 側(cè)架的支持上從同樣的位置那里的腿是安裝在側(cè)架。 8的軌跡輸送機(jī)路段觀(guān)察任何異常在大負(fù)載。負(fù)載的應(yīng)用于實(shí)驗(yàn)輸送機(jī)部分在估算和高于實(shí)際負(fù)荷欺詐-在真正輸送機(jī)系統(tǒng)條件應(yīng)用。輸送設(shè)備的通常用來(lái)攜帶下的荷載一公噸,每米 工業(yè)應(yīng)用于食品和飲料行業(yè)。掣普珥-應(yīng)用大量的輪廓點(diǎn)是估計(jì)偏轉(zhuǎn)對(duì)側(cè)架在高負(fù)載下。數(shù)字6和7取得成果的 通過(guò)實(shí)驗(yàn)對(duì)輸送機(jī)的四個(gè)進(jìn)程和部分六軌,分別。 從獲得的結(jié)果,觀(guān)察2 KN下?lián)隙戎档暮奢d作用下,幾乎是在2毫米 圖5 圖6 圖7 類(lèi)型的部分。在一定情況下,1.6毫米不銹鋼側(cè)架的設(shè)計(jì),可以一種可能的選擇在現(xiàn)有的輸送機(jī)側(cè)架的設(shè)計(jì)。據(jù)預(yù)計(jì),有更大的部分,對(duì)輸送帶撓度的側(cè)架的意志呆在允許范圍內(nèi),也就是說(shuō),±5毫米。主要的是為什么這個(gè)試驗(yàn)是確保側(cè)架裂紋不扣在高負(fù)載下。因此沒(méi)有 對(duì)于任何證據(jù)屈曲發(fā)生的各種類(lèi)型的部分使用。但預(yù)計(jì)也,經(jīng)驗(yàn)教訓(xùn)的基礎(chǔ)上工程師和調(diào)查研究,在當(dāng)前完整的總成后,輸送設(shè)備想像的力量,這將進(jìn)一步額外減少可靠性偏斜對(duì)側(cè)架。例如,撓度,對(duì)于每一套測(cè)量實(shí)驗(yàn)的意義。與安裝在側(cè)架腿,部隊(duì)將行為相反的方向,將極大推動(dòng)側(cè)架里面。完整的觀(guān)察可見(jiàn)特發(fā)性肺纖維化-保護(hù)的這個(gè)假設(shè)當(dāng)一個(gè)完整可以得出結(jié)論 輸送機(jī)是內(nèi)制造和測(cè)試試驗(yàn)的基礎(chǔ)上的新設(shè)計(jì)參數(shù)。 所有的實(shí)驗(yàn)結(jié)果,得到了令人滿(mǎn)意的結(jié)果,它是騙人的-那1.6毫米不銹鋼304側(cè)架品位是專(zhuān)為輸送帶,對(duì)于食物和飲料行業(yè) 指定的指導(dǎo)方針下負(fù)載。制造的成本節(jié)約這個(gè)地區(qū)有顯著的自預(yù)計(jì)80%的材料的用量在一個(gè)輸送系統(tǒng)是不銹鋼做的。 6.2側(cè)架成本分析 物料檢討和撓度的分析表明了現(xiàn)有2.5毫米不銹鋼薄板設(shè)計(jì)是一個(gè)在身邊的時(shí)候我是誰(shuí)框架的食品和飲料輸送機(jī)應(yīng)用。alysis也顯示,1.6毫米厚的不銹鋼薄板即可作為一種替代性材料為側(cè)架,這將履行令人滿(mǎn)意。表5顯示一個(gè)比較成本的舊的,新設(shè)計(jì)的側(cè)架,哪個(gè) 表明,節(jié)約每側(cè)架在新設(shè)計(jì)是37億美元(例如:一個(gè)儲(chǔ)蓄的50.1%)。除此之外,節(jié)約成本,減少側(cè)架從尺寸241 mm 199 mm也將允許生產(chǎn)一個(gè)額外側(cè)架的3000×1500毫米不銹鋼。 在圖紙上。新設(shè)計(jì)的改善是開(kāi)展了好幾個(gè)其他關(guān)鍵的部位,如支持渠道,還滾子軸上,穿條間隔的酒吧,支持和支持,一端穿帶 導(dǎo)致更多的成本和勞動(dòng)的儲(chǔ)蓄和緩解肌肉吉諾比利-成和組裝等。例如,新的設(shè)計(jì)的支持總成(包括支持渠道穿帶和一端穿條)要求降低若干進(jìn)程,減少磨損的紙條厚度、使用一個(gè)新的M截面通道和規(guī)定使用不同種類(lèi)的鏈給人們提供了一種節(jié)約成本的33.7%實(shí)驗(yàn)結(jié)果表明,改進(jìn)的設(shè)計(jì)。這種新設(shè)計(jì)的輥軸的回報(bào)-用一種節(jié)約成本和減少50% 44.5%的勞動(dòng)力時(shí)間。這種新設(shè)計(jì)間隔酒吧提供費(fèi)用估計(jì)從節(jié)省25%的舊的設(shè)計(jì)。 7 一個(gè)在測(cè)試設(shè)計(jì)實(shí)施的輸送系統(tǒng) 設(shè)計(jì)改進(jìn)的實(shí)施零件和部件進(jìn)行設(shè)計(jì),圖靈測(cè)試和組裝的一個(gè)較為完整的輸送系統(tǒng)。這新的和改進(jìn)的測(cè)試和驗(yàn)證輸送機(jī)當(dāng)時(shí)性能與實(shí)際產(chǎn)品(塑膠瓶)。分析了成本——還進(jìn)行了比較sis是整體成本的儲(chǔ)蓄,在這個(gè)測(cè)試輸送機(jī)與所涉及的費(fèi)用與一個(gè)相同的輸送機(jī) 基于陳舊的設(shè)計(jì)[7]。新的考試輸送機(jī)是一種類(lèi)型(圖8),共有三個(gè)不同的部分的總長(zhǎng)度5米。部分six-track C1是一段截面C2輸送機(jī),加入是一個(gè)six-track彎曲90?輸送機(jī)。這是連接到輸送機(jī)補(bǔ)體C3,它是一段eight-track輸送機(jī)的部分,稱(chēng)為雜合- 國(guó)家的兩種不同類(lèi)型的枷鎖,標(biāo)簽和力量。測(cè)試輸送含有共有26主要部分。圖9所示的是用于測(cè)試的測(cè)試輸送機(jī)在合作產(chǎn)品開(kāi)發(fā)流程 公司。性能和效率的新測(cè)試方法的輸送機(jī)和它的重要的新零件進(jìn)行了光滑、無(wú)噪音的表演-通過(guò)觀(guān)察極佳的產(chǎn)品開(kāi)發(fā)流程的空的塑膠喝瓶輸送鏈條。所有的器官和輸送系統(tǒng)發(fā)現(xiàn)良好的靜動(dòng)態(tài)性能充分展示功能。一個(gè)完整的成本分析在測(cè)試輸送機(jī)進(jìn)行了研究 為了衡量不同新與舊的設(shè)計(jì)也在組裝評(píng)價(jià)緩解和減少勞動(dòng)expendi -真正的。部件數(shù)量,所用的原材料、生產(chǎn)成本進(jìn)行了計(jì)算和百分比等各個(gè)部分的存款每一部分和整體系統(tǒng)進(jìn)行測(cè)定。 圖8 圖9 8結(jié)果和討論 最關(guān)鍵的面積來(lái)查看是否考慮是新的支持通道的設(shè)置和滴盤(pán)中加入已經(jīng)執(zhí)行用較少的勞動(dòng)消耗。注意的是,也已經(jīng)向 確保勞動(dòng)者已經(jīng)工作有效地工作。 《紐約時(shí)報(bào)》用于組裝的輸送系統(tǒng)是在意料之中的對(duì)取決于心情的工人和其他外部前沿空中管制官-工具。但是努力達(dá)到盡可能密切的時(shí)間制造的輸送設(shè)備。一項(xiàng)研究揭示了證明成本分析的事實(shí):生產(chǎn)成本節(jié)約?40%或更多達(dá)到了 八改良設(shè)計(jì)部分節(jié)約成本實(shí)現(xiàn)了26%,34%在其他三個(gè)部分組成。 ?在高成本部分,最大的儲(chǔ)蓄為實(shí)現(xiàn)軸側(cè)架,還輥,腿集和支持穿條紋的。 ?的總費(fèi)用降低了19%的輸送機(jī)。 ?整體勞動(dòng)力成本在裝配的輸送機(jī)降低了20%。 研究表明,該儲(chǔ)蓄完成主要輸送機(jī)的零件,達(dá)到或超過(guò)設(shè)計(jì) 不是設(shè)計(jì)專(zhuān)業(yè)。其中最主要的變化,這些變化輸送機(jī)系統(tǒng)的影響是設(shè)計(jì)的修訂側(cè)架的設(shè)計(jì)參數(shù),這也會(huì)影響到這些變化在其他地方,都是同盟。其次,發(fā)展支持新的M剖面的通道隨著標(biāo)準(zhǔn)磨損 條添加到巨大的成就在新的輸送機(jī)的設(shè)計(jì)。完成從全新的設(shè)計(jì)減少了勞動(dòng)也做出了重大影響成本和流水線(xiàn)上提高了產(chǎn)品設(shè)計(jì)和制造。同時(shí)也注意到,它是由categorising間隔棒不同數(shù)量的軌跡im - 證明了選拔程序的設(shè)計(jì)。新輸送機(jī)制度已成為更經(jīng)濟(jì)且有效的成本和需求使用額外的增強(qiáng)材料被淘汰出局。 9結(jié)論 在設(shè)計(jì)和制造機(jī)械輸送系統(tǒng)-等方面,有相當(dāng)不足的研究工作的輸送機(jī)設(shè)計(jì)優(yōu)化,特別是缺乏應(yīng)用技術(shù)來(lái)設(shè)計(jì)改進(jìn)在這樣的系統(tǒng)。在為了提高成本和訂貨至交貨的時(shí)間——在輸送系統(tǒng) 瞬變電磁法(tem)、一個(gè)完整的故障分析,這也是一種試輸送機(jī)等久了進(jìn)行評(píng)估的高消費(fèi)地區(qū)于輸送機(jī)馬努-成。分析運(yùn)用原則的支持 可制造性設(shè)計(jì),為提高面向裝配的設(shè)計(jì)在不犧牲的功能設(shè)計(jì)和運(yùn)行的系統(tǒng)。一種新的式輸送機(jī)設(shè)計(jì)提出了一種基于所有 建議的修改的自動(dòng)調(diào)節(jié)式氣力輸送的組件。該建議驗(yàn)證了輸送系統(tǒng)以及在考試的時(shí)候所采用的合作公司。結(jié)果證明見(jiàn)sub - cessful與整體的儲(chǔ)蓄,在成本和19%下降20%總勞動(dòng)成本。研究結(jié)果顯示,應(yīng)用DFMA的規(guī)則,設(shè)計(jì)和組裝的費(fèi)用的一個(gè)情結(jié) 像機(jī)械輸送系統(tǒng)為食品加工即可戲劇性的減少。 參考 1. Anderasen MM, Ahm T (1986) Flexible assembly system. Springer, Berlin Heidelberg New York 2. Ho JKL, Ranky PG (1994) The design and operation control of a recon- figurable ?exible material handling. Proceedings of 1994 Japan-USA Symposium of Flexible Automation, vol. 2, Kobe, Japan, pp 825-828 3. Ho JKL, Ranky PG (1997) Object oriented modelling and design of reconfigurable conveyors in ?exible assembly systems. Int J Comput Integr Manuf 10(5):360-379 4. Kusiak A (1990) Intelligent manufacturing systems. Prentice Hall, New York 5. Corbett J, Dooner M, Meleka J, Pym C (1991) Design for manufactur- ing: strategies principles and techniques. Addison-Wesley, UK 6. Mize JH, Glenn P (1989) Some fundamentals of integrated manufac- turing. International Industrial Engineering Conference Proceedings, Washington, DC, pp 546-551 7. Mize JH (1987) CIM-a perspective for the future of IE's. IIE Integrated Systems Conference Proceedings, Nashville, TN, pp 3-5 8. Boothroyd G, Dewhurst P (1988) Product design for manufacturing and assembly. Manuf Eng April:42-46 9. Bedworth DD, Henderson MR, Wolfe PM (1991) Computer integrated design and manufacturing. McGraw-Hill, Singapore 10. Abbas B (2001) An investigation into design and manufacturing of mechanical systems for food processing and beverage industry. Disser- tation, Swinburne University of Technology, Hawthorn, Australia DOI 10.1007/s00170-003-1843-3 ORIGINAL ARTICLE Int J Adv Manuf Technol (2005) 25: 551559 S.H. Masood B. Abbas E. Shayan A. Kara An investigation into design and manufacturing of mechanical conveyors systems for food processing Received: 29 March 2003 / Accepted: 21 June 2003 / Published online: 23 June 2004 Springer-Verlag London Limited 2004 Abstract This paper presents the results of a research investi- gation undertaken to develop methodologies and techniques that will reduce the cost and time of the design, manufacturing and assembly of mechanical conveyor systems used in the food and beverage industry. The improved methodology for design and production of conveyor components is based on the minimisa- tion of materials, parts and costs, using the rules of design for manufacture and design for assembly. Results obtained on a test conveyor system verify the benefits of using the improved tech- niques. The overall material cost was reduced by 19% and the overall assembly cost was reduced by 20% compared to conven- tional methods. Keywords Assembly Cost reduction Design DFA DFM Mechanical conveyor 1 Introduction Conveyor systems used in the food and beverage industry are highly automated custom made structures consisting of a large number of parts and designed to carry products such as food cartons, drink bottles and cans in fast production and assembly lines. 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 filling or assembly oper- ations. Their operations require highly efficient and reliable me- chanical conveyors, which range from overhead types to floor- mounted types of chain, roller or belt driven conveyor systems. In recent years, immense pressure from clients for low cost but efficient mechanical conveyor systems has pushed con- veyor manufacturers to review their current design and assembly methods and look at an alternative means to manufacture more economical and reliable conveyors for their clients. At present, S.H. Masood (a117) B. Abbas E. Shayan A. Kara Industrial Research Institute Swinburne, Swinburne University of Technology, Hawthorn, Melbourne 3122, Australia E-mail: smasoodswin.edu.au most material handling devices, both hardware and software, are highly specialised, inflexible and costly to configure, install and maintain 1. Conveyors are fixed in terms of their locations and the conveyor belts according to their synchronised speeds, mak- ing any changeover of the conveyor system very difficult and ex- pensive. In todays radically changing industrial markets, there is a need to implement a new manufacturing strategy, a new system operational concept and a new system control software and hard- ware development concept, that can be applied to the design of a new generation of open, flexible material handling systems 2. Ho and Ranky 3 proposed a new modular and reconfigurable 2D and 3D conveyor system, which encompasses an open re- configurable software architecture based on the CIM-OSA (open system architecture) model. It is noted that the research in the area of improvement of conveyor systems used in beverage in- dustry is very limited. Most of the published research is directed towards 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 floor mounted type chain driven 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 for manufacturing and design for assembly 4, 5, several critical conveyor parts were investigated for their functionality, material suitability, strength criterion, cost and ease of assembly in the overall conveyor system. The critical parts were modified and redesigned with new shape and geometry, and some with new materials. The improved design methods and the functionality of new conveyor parts were verified and tested on a new test con- veyor system designed, manufactured and assembled using the new improved parts. 2 Design for manufacturing and assembly (DFMA) In recent years, research in the area of design for manufacturing and assembly has become very useful for industries that are con- 552 sidering improving their facilities and manufacturing methodol- ogy. However, there has not been enough work done in the area of design for conveyor components, especially related to the is- sue of increasing numbers of drawing data and re-engineering of the process of conveyor design based on traditional methods. A 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, efficient and cost effective for the companies under investigation. The main classifications of DFMA knowledge can be iden- tified as (1) General guidelines, (2) Company-specific best prac- tice or (3) Process and or resource-specific constraints. General guidelines refer to generally applicable rules-of-thumb, relat- ing to a manufacturing domain of which the designer should be aware. The following list has been compiled for DFM guidelines 6. Design for a minimum number of parts Develop a modular design Minimise part variations Design parts to be multifunctional Design parts for multiuse Design parts for ease of fabrication Avoid separate fasteners Maximise compliance: design for ease of assembly Minimise handling: design for handling presentation Evaluate assembly methods Eliminate adjustments Avoid flexible components: they are difficult to handle Use parts of known capability Allow for maximum intolerance of parts Use known and proven vendors and suppliers Use parts at derated values with no marginal overstress Minimise subassemblies Fig.1. Layout of conveyor sys- tem for labelling plasic bottles Emphasise standardisation Use the simplest possible operations Use operations of known capability Minimise setups and interventions Undertake engineering changes in batches These design guidelines should be thought of as “optimal suggestions”. They typically will result in a high-quality, low- cost, and manufacturable design. Occasionally compromises must be made, of course. In these cases, if a guideline goes against a marketing or performance requirement, the next best alternative should be selected 7. Company-specific best practice refers to the in-house design rules a company develops, usually over a long period of time, and which the designer is expected to adhere to. These design rules are identified by the company as contributing to improved quality and efficiency by recognising the overall relationships between particular processes and design decisions. Companies use such guidelines as part of the training given to designers of products requiring significant amounts of manual assembly or mainte- nance. Note that most of the methodologies are good at either being quick and easy to start or being more formal and quanti- tative. For example, guidelines by Boothroyd and Dewhurst 8 on DFA are considered as being quantitative and systematic. Whereas the DFM guidelines, which are merely rules of thumb derived from experienced professionals, are more qualitative and less formal 9. 3 Conventional conveyor system design Design and manufacturing of conveyor systems is a very com- plex and time-consuming process. As every conveyor system is a custom-made product, each project varies from every other project in terms of size, product and layout. The system design 553 is based on client requirements and product specifications. More- over, the system layout has to fit in the space provided by the company. The process of designing a layout for a conveyor sys- tem involve revisions and could take from days to months or in some instances years. One with the minimum cost and maximum client suitability is most likely to get approval. Figure 1 shows a schematic layout of a typical conveyor system installed in a production line used for labelling of plastic bottles. Different sections of the conveyor system are identified by specific technical names, which are commonly used in similar industrial application. The “singlizer” sec- tion enables the product to form into one lane from multiple lanes. The “slowdown table” reduces the speed of product once it exits from filler, labeller, etc. The “mass flow” sec- tion is used to keep up with high-speed process, e.g., filler, labeller, etc. The “transfer table” transfers the direction of prod- uct flow. The purpose of these different conveyor sections is thus to control the product flow through different processing machines. A typical mechanical conveyor system used in food and bev- erage applications consists of over two hundred mechanical and electrical parts depending on the size of the system. Some of the common but essential components that could be standard- ised and accumulated into families of the conveyor system are side frames, spacer bars, end plates, cover plates, inside bend plates, outside bend plates, bend tracks and shafts (drive, tail and slave). The size and quantity of these parts vary according to the length of conveyor sections and number of tracks correspond- ing to the width and types of chains required. The problems and shortcomings in the current design, manufacturing and assembly of mechanical conveyors are varied, but include: Over design of some parts High cost of some components Long hours involved in assembly/maintenance Use of non-standard parts Table 1. Conveyor critical parts based on parts cost analysis Product description Qty Material used Cost (%) Improvement possible (Yes/No) Leg set 68 Plastic leg + SS tube 20.22 Yes Side frame 80 2.5 mm SS 16.07 Yes Support channel 400 C channel SS 15.00 Yes Bend tracks 8 Plastic 14.36 No Rt. roller shaft 139 20 dia. SS shaft 6.70 Yes Tail shaft 39 35 dia. Stainless steel 6.27 No Spacer bar 135 50X50X6 SS 5.43 Yes Support wear strip 400 40 10 mm plastic 5.36 Yes Support side wear strip 132 Plastic 3.01 Yes End plate 39 2.5mm/SS 1.88 Yes Cover plate 39 1.6 mm S/S 1.57 No Bend plates 8 2.5mm/SS 1.29 Yes Torque arm bracket 18 6 mm S/S plate 1.21 Yes Slot cover 97 Stainless steel 0.97 Yes Inside bend plate 8 2.5mm/SS 0.66 Yes Total 100.00 Critical parts 4 Areas of improvement In order to identify the areas of cost reduction in material and labour, a cost analysis of all main conveyor parts was conducted to estimate the percentage of cost of each part in relation to the total cost of all such parts. The purpose of this analysis was to identify the critical parts, which are mainly responsible for in- creasing the cost of the conveyor and thereby investigate means for 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 further improvements in design to reduce the cost is possible. Out of these, seven parts were identified as critical parts (shown by an asterisk in Table 1) constituting maximum number of compo- nents in quantity and comprising over 71% of overall material cost. Among these, three components (leg set, side frame and support channel) were found to account for 50% of the total conveyor material cost. A detailed analysis of each of these 12 parts was carried out considering the principles of concurrent en- gineering, design for manufacture and design for assembly, and a new improved design was developed for each case 10. De- tails of design improvement of some selected major component are presented below. 5 Redesign of leg set assembly In a conveyor system, the legs are mounted on the side frame to keep the entire conveyor system off the floor. The existing design of conveyor legs work, but they are costly to manufacture, they have stability problems, and cause delays in deliveries. The delay is usually caused by some of the parts not arriving from over- seas suppliers on time. The most critical specifications required for the conveyor legs are: 554 Strength to carry conveyor load Stability Ease of assembly Ease of flexibility (for adjusting height) Figure 2 indicates all the parts for the existing design of the conveyor leg. The indicated numbers are the part numbers described 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 leg brackets ordered from overseas, stainless steel leg tubes, which are cut into specified sizes, leg tube plastic adjustments, which are 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 leg tube to bolt the angle cross bracing and backing plate to support leg brackets bolts. The # of parts in Table 2 signifies the number of components in each part number and the quantity is the con- sumption of each part in the leg design. Companies have used this design for many years but one of the common complaints reported 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 (part Fig.2. Existing leg design assembly with part names shown in Table 1 Table 2. Cost analysis for old leg design assembly Part no. Part description # of parts Qty Cost Source 1 Plastic leg bracket 2 2 $ 30.00 Overseas 5, 6 Leg tube plastic adjustment 4 2 $ 28.00 Overseas 4 Lug 2 2 $ 4.00 In-house 7 Angle cross bracing 1 1 $ 5.00 In-house 2 Backing plate 2 2 $ 4.00 In-house 3 Leg tube 2 2 $ 25.00 In-house 8 Bolts 6 6 $ 3.00 In-house Total assembly cost (welding) $ 15.00 In-house Total 19 17 $ 114.00 1 and part 3 in Fig. 2) was not rigid enough. The connections for these parts are only a single 6 mm bolt. At times, when the conveyor system was carrying full product loads, it was observed that the conveyor legs were unstable and caused mechanical vi- bration. One of the main reasons for this was due to a single bolt connection at each end of the lugs in part 3 and part 7. The sta- bility of the conveyor is considered critical matter and requires rectification immediately to satisfy customer expectations. Considering the problems of the existing conveyor leg de- sign and the clients preferences, a new design for the conveyor leg was developed. Generally the stability and the strength of the legs were considered as the primary criteria for improve- ment in the new design proposal but other considerations were the simplicity of design, minimisation of overseas parts and ease of assembly at the point of commissioning. Figure 3 shows, the new design of the conveyors leg assembly, and Table 3 gives a description and the cost of each part. Figure 3 shows that the new design consists of only five main parts for the conveyors leg compared to eight main parts in the old design. In the old design, the plastic leg bracket, the leg tube plastic adjustment and the leg tube were the most expensive items accounting for 72% of the cost of leg assembly. In the new 555 Fig.3. New design for leg assembly with part names in Table 3 Table 3. Cost analysis for new design leg assembly Part no. Part description # of parts Qty Cost Source 1 Stainless steel angle (50503 mm) 2 2 $ 24.00 In-house 3 Leg plastic adjustment 2 2 $ 10.00 Overseas 4 Cross brassing 1 1 $ 7.00 In-house 5 Bolts 8 4 $ 4.00 In-house 2 Backing plate 2 2 $ 4.00 In-house Total assembly cost $ 10.00 In-house Total 15 11 $ 59.00 design, those parts have been replaced by a stainless steel angle and a new plastic leg adjustment reducing the cost of leg assem- bly by almost 50%. Thus the total numbers of parts in the leg have been reduced from 19 to 15 and the total cost per leg setup has been reduced by $ 55 in the new design. The new conveyor leg design, when tested, was found to be more secure and stable than the old design. The elimination of part number 1 and 5 from old conveyor design has made the new design more stable and rigid. In addition, the width of the cross bracing has also been increased with two bolts mount instead of one in old design. This has provided the entire conveyor leg setup an additional strength. 6 Redesign of the side frames The side frame is the primary support of a conveyor system that provides physical strength to conveyors and almost all the parts are mounted on it. The side frame is also expected to have a rigid strength to provide support to all the loads carried on the conveyor. It also accommodates all the associated conveyor components for the assembly. The critical considerations of side frame design are: Size of side frame (depth) Strength of the material Ease for assembly Ease for manufacturing 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 initial investigation, it was found that the distance between spacer bar holes and return shaft (dimensions G and F in Fig. 4) could be reduced, as there was some unnecessary gap between those two components. The important point to check before redefining the design parameters was to make sure that after bringing those two closer, the return chains would not catch the spacer bar while the conveyor is running. The model of the new side frame design was drawn on CAD to ensure all the specifications are sound and the parts are placed in the position to check the clearances and the fits. Using the principle of design for manufacturing the new side frame design was made symmetrical so that it applies to all types of side frames. This change is expected to reduce the size of side frame significantly for all sizes of chains. Table 4 shows a comparison of dimensions in the old design and the new design of side frames for the same chain type. It 556 Fig.4. Side frame dimensions Table 4. New and old side frame dimension parameters Old design Chain type A B C D E F G H I J K L 3.25 primeprime LF/SS STR/LBP/MAG 31 92 71 196 65 105 211 241 136 58 85 196 TAB 22 83 62 187 56 96 202 232 127 New design Chain type A B C D E F G H I J K L 3.25 primeprime LF/SS STR/LBP/MAG/TAB 31 100 73 173 67 107 167 199 92 58 85 152 is noted that the overall size (depth) of the conveyor has been reduced from 241 mm to 199 mm (dimension H), which gives a saving of 42 mm of stainless steel on every side frame manu- factured. Thus, from a stainless steel sheet 1500 3000 mm, the old design parameters allowed only six 3 m long side frames but with the new design parameter now it was possible to produce seven side frames of 3 m long from the same sheet size. The amount of material used for side frames was also re- viewed for further investigation. It is estimated that about 55% of the total cost of the conveyor system is spent on materials. The current material used for side frames is 2.5 mm thick stain- less steel food grade 304. Currently, there are other materials available in the market with alternative thickness that could be considered as an option. For this, a deflection analysis has been conducted to estimate if there was any other type of material suit- able to replace the existing material so that it does not fail its strength criteria. 6.1 Deflection analysis for side frames Figure 5 shows the experimental setup to determine the deflec- tion of new side frame in X and Y direction under different loading conditions. With the new design parameters a set of side frames were manufactured to investigate the deflection on 1.6 mm thick stainless steel side frames. A section of side frame bolted with spacer bar and return shaft was assembled for test- ing with the experiment. The