《及时化生产系统.ppt》由会员分享，可在线阅读，更多相关《及时化生产系统.ppt（74页珍藏版）》请在三一办公上搜索。
1、及時化生產系統,1,及時化(just in time，JIT)概述,提出者：豐田汽車副社長，大野耐一(Taiichi Ohno)。意義將需要的物品在必須的時間供應必須的品質與數量到需要的地點。目的消除混亂使系統彈性化降低籌置與前置時間存量最小化消除浪費,及時化生產系統,2,JIT目標和建築架構的歸納,及時化生產系統,3,常見的資源浪費1,超額生產(overproduction)等候時間(waiting time)不必要的運送(unnecessary transporting)存貨(inventory)加工浪費(processing waste)不必要的生產步驟產出瑕疵品,及時化生產系統,4,常
2、見的資源浪費2,無效的工作方法(inefficient work method)不佳的佈置和物料搬運模式，增加在製品存貨產品不良再製成本消費者不滿意造成銷售損失,及時化生產系統,5,Waste in Operations,及時化生產系統,6,Waste in Operations,及時化生產系統,7,Waste in Operations,及時化生產系統,8,消除浪費之改善哲學1,視浪費為敵人，消除浪費是首要之務。改善需逐步且持續地進行，而非間歇性地進行大規模改善。每個人都必須參與。改善原則在於利用經濟的策略即可達成，不需花費昂貴的技術或顧問。改善的方法可以應用於各種地方。,及時化生產系統,9
3、,消除浪費之改善哲學2,藉由目視系統達成：作業程序和製程等皆透明化，使得問題與浪費清晰易見。專注於創造價值之處。以流程為導向。主要的改善努力著重於新的想法和新的工作方式。組織學習的本質即為做中學。,及時化生產系統,10,Basic Elements of JIT1,標準的零件(產品設計)模組化設計(產品設計)高產能的系統(產品設計)可同時生產(產品設計),將員工視為資產(人員/組織的要素)訓練員工，使其變成多能工(人員/組織的要素)持續改善(人員/組織的要素)成本會計(人員/組織的要素)領導與專案管理(人員/組織的要素),及時化生產系統,11,Basic Elements of JIT2,Ce
4、llular layouts(製程設計Pull production system(製造規劃與控制)Flexible resources(製程設計)Kanban production control(製造規劃與控制)Small-lot production(製程設計),Quick setups(製程設計)Uniform production levels(製造規劃與控制)Quality at the source(製程設計)Total productive maintenance(製造規劃與控制)Supplier networks(製造規劃與控制),及時化生產系統,12,Flexible Re
5、sources,Multifunctional workers(多能工)Perform more than one jobGeneral purpose machines(通用設備)Perform several basic functionsStudy operators&improve operations,及時化生產系統,13,Cellular Layouts,Group dissimilar machines in manufacturing cell to produce family of partsWork flows in one direction through cellC
6、ycle time adjusted by changing worker paths,及時化生產系統,14,Manufacturing Cell with Worker Routes,及時化生產系統,15,Worker Routes Lengthened as Volume Decreases,及時化生產系統,16,推式與拉式系統,推式系統(push system)(例如，MPR)當工作在某工作站完成時，產出就被推往下一站。拉式系統(pull system)(例如，JIT)工作移動的控制落於下一站;每一工作站從前一站拉拔所需產出。,及時化生產系統,17,Kanban Production C
7、ontrol System(看板生產管制系統),Kanban card indicates standard quantity of productionDerived from two-bin inventory system(雙倉制)Kanban maintains discipline of pull productionProduction kanban(生產看板)authorizes productionWithdrawal kanban(提領看板)authorizes movement of goods,及時化生產系統,18,A Sample of Kanban,及時化生產系統,1
8、9,The Origin of Kanban,及時化生產系統,20,Single-Card Kanban System,及時化生產系統,21,Storage area,Empty containers,Full containers,Single-Card Kanban System,Receiving post,Kanban card for product 1,Kanban card for product 2,及時化生產系統,22,Storage area,Empty containers,Full containers,Single-Card Kanban System,Receivi
9、ng post,Kanban card for product 1,Kanban card for product 2,及時化生產系統,23,Storage area,Empty containers,Full containers,Single-Card Kanban System,Receiving post,Kanban card for product 1,Kanban card for product 2,及時化生產系統,24,Storage area,Empty containers,Full containers,Single-Card Kanban System,Receivi
10、ng post,Kanban card for product 1,Kanban card for product 2,及時化生產系統,25,Storage area,Empty containers,Full containers,Single-Card Kanban System,Receiving post,Kanban card for product 1,Kanban card for product 2,及時化生產系統,26,Storage area,Empty containers,Full containers,Single-Card Kanban System,Receivi
11、ng post,Kanban card for product 1,Kanban card for product 2,Fabrication cell,O1,O2,O3,O2,及時化生產系統,27,看板系統 single kanban,及時化生產系統,28,Types of Kanbans Dual kanbans,及時化生產系統,29,Dual kanban vs.single kanban,Dual kanbanIs used when material is not necessarily moving between two consecutive processes,or when
12、 there is more than one input to a process and the inputs are dispersed throughout the facility.Single kanbanIs used when the processes are tightly linked.,及時化生產系統,30,Types of Kanbans,Kanban SquareMarked area designed to hold itemsSignal KanbanTriangular kanban used to signal production at the previ
13、ous workstationMaterial KanbanUsed to order material in advance of a processSupplier KanbansRotate between the factory and suppliers,及時化生產系統,31,Types of Kanbans kanban square and kanban racks,及時化生產系統,32,Types of Kanbans signal kanbans,及時化生產系統,33,看板管理系統之規則,不要把不良品交給後製程。由後製程到前製程來領取零件。前製程僅生產將被後製程領用去的數量。
14、生產必須平衡。看板只做為微調整的手段，其張數必須減到最少。製程必須安定化、合理化。,及時化生產系統,34,Single-Card Kanban System,KANBAN,Part Number:1234567ZLocation:Aisle 5Bin 47Lot Quantity:6Supplier:WS 83Customer:WS 116,Each container must have a cardAssembly always withdraws from fabrication(pull system)Containers cannot be moved without a kanba
15、nContainers should contain the same number of partsOnly good parts are passed alongProduction should not exceed authorization,及時化生產系統,35,看板(容器)數量之決定1,K=容器數量。d=工作中心之計劃使用率(預期每日需求)。p=每箱容器零件之平均加工時間。W=在生產過程中之平均等候時間，加上每箱物料的搬運時間。C=標準容器之零件容量。X=政策變數。反應生產系統的效率(10%以內),及時化生產系統,36,看板(容器)數量之決定2,及時化生產系統,37,看板(容器)數
16、量之決定3,whereN=number of kanbans or containersd=average demand over some time periodL=lead time to replenish an orderS=safety stockC=container size,及時化生產系統,38,容器數量決定範例,某汽車零件公司生產4輪傳動車的方向盤及暫停系統中的搖桿手臂組合。一般1箱零件在製造週期中需要0.02天的加工及0.08天的物料處理和等候時間。零件每日的需求為2000個單位。管理部門認為搖桿手臂組合的需求不確定，所以其安全庫存為需求量的10%。若每箱內各有22個零件，
17、則應授權的箱子數量為多少。,及時化生產系統,39,小批量(Small-lot production)的效益,降低在製品存貨減少因品質發生問題時所產生的檢驗和重加工成本減少儲存空間問題更容易顯現增加生產彈性易於進行作業平衡,及時化生產系統,40,Inventory Hides Problems,及時化生產系統,41,Lower Levels of Inventory Expose Problems,及時化生產系統,42,Components of Lead Time(前置時間的元素),Processing timeReduce number of items or improve efficie
18、ncyMove timeReduce distances,simplify movements,standardize routingsWaiting timeBetter scheduling,sufficient capacitySetup timeGenerally the biggest bottleneck,及時化生產系統,43,快速籌置(Quick setups),Single-digit setupThe goal of having a setup time of less than 10 minutes.快速換模又稱一分鐘換模術(single-minute exchange
19、of dies,SMED),及時化生產系統,44,快速籌置的實施步驟,1.將換模作業流程劃分外部整備作業與內部整備作業。2.儘可能把內部整備作業改變成外部整備作業。3.消除內部整備所需的調整作業。4.外部整備作業的標準化。5.推動平行作業。6.利用機械提高換模效率。7.其他管理部門的充分配合。,及時化生產系統,45,問題討論教學成效之提昇,內整備：基礎觀念之講解(例如，品質管理課程之統計概念)外整備：課前預習課後復習,及時化生產系統,46,Common Techniques for Reducing Setup Time1,及時化生產系統,47,Common Techniques for Re
20、ducing Setup Time2,及時化生產系統,48,Common Techniques for Reducing Setup Time3,及時化生產系統,49,平準化生產(Uniform Production),Results from smoothing production requirementsKanban systems can handle+/-10%demand changesThe way to reduce variability in productionSmooths demand across planning horizonMixed-model assemb
21、ly steadies component production,及時化生產系統,50,平準化範例1,The APP of TOYOTA:4500 vehicles per week.Two full shifts,five days per week 450 vehicles per shift(480 minutes)Three models are produced:Camry(C),Avalon(A),and Sienna(S).200 Camry,150 Avalons,and 100 Siennas per shiftCycle time:480/450=1.067(min),及時
22、化生產系統,51,平準化範例2,First 200 Cs 150 As 100SsHigh average cycle inventory levelLumpy requirementsSecond4 Cs 3 As 2Ss The cycle=9(1.067)=9.60(50 times per shift),及時化生產系統,52,平準化範例3,ThirdC S C A C A C S AThe setup times must be very short.Component requirements is steadyCapacity requirements are smoothed,及
23、時化生產系統,53,Quality at the Source1,Jidoka(自働化)在生產過程中自動偵測缺點Andon(安童)在每個工作站裝置燈號系統，以指示問題及落後狀態。Undercapacity scheduling allows for planning，problem solving&maintenance,及時化生產系統,54,Quality at the Source2,防呆裝置日文發音為POKAYOKE，是指在模具，工具，機器設備上設計防止錯誤(不良)發生的裝置，一旦作業員做錯或需要作業上的警示時，防呆裝置可以預防或使機器停下來，確保不產生不良品。目視管理系統(visual
24、 control)：係透過顯示板之顯示得以快速且明顯地發現異常、浪費、故障、斷料等現場不順暢之情形，而達到能速謀對策的一種管理系統。,及時化生產系統,55,Visual Control,及時化生產系統,56,Visual Control,及時化生產系統,57,Visual Control,及時化生產系統,58,Kaizen(改善),Continuous improvementRequires total employment involvementEssence of JIT is willingness of workers toSpot quality problemsHalt produ
25、ction when necessaryGenerate ideas for improvementAnalyze problemsPerform different functions,及時化生產系統,59,Total Productive Maintenance(TPM),Breakdown maintenanceRepairs to make failed machine operationalPreventive maintenanceSystem of periodic inspection&maintenance to keep machines operatingTPM comb
26、ines preventive maintenance&total quality concepts,及時化生產系統,60,TPM Requires Management to:,Design products that can be easily produced on existing machinesDesign machines for easier operation,changeover,maintenanceTrain&retrain workers to operate machinesPurchase machines that maximize productive pot
27、entialDesign preventive maintenance plan spanning life of machine,及時化生產系統,61,導入JIT的基礎5S運動,及時化生產系統,62,Supplier Policies1,Locate near to the customerUse small,side loaded trucks and ship mixed loadsConsider establishing small warehouses near to the customer or consolidating warehouses with other suppl
28、iers,及時化生產系統,63,Supplier Policies2,Use standardized containers and make deliveries according to a precise delivery scheduleBecome a certified supplier and accept payment at regular intervals rather than upon delivery,及時化生產系統,64,及時生產系統(JIT II),供應商進入工廠，成為客戶採購部門的積極成員，駐廠代表取代採購人員、銷售人員，甚至物料規劃人員。,及時化生產系統,6
29、5,推行JIT之要素1,獲得高階管理者的支持並確保他們了解所需要的資源。仔細地對生產作業進行研究，以決定哪些部分需要特別努力。獲得員工的支持和合作，並準備員工訓練計畫。轉換之初，先由降低設置時間開始。從製程最末端開始往前，慢慢地轉換作業。,及時化生產系統,66,推行JIT之要素2,轉換供應商的系統成為 JIT，並與其緊密合作。要有克服轉換障礙的準備。正確之銷售預測可有效縮短製造前置時間。生產部門依訂單及長、短期預測，規劃生產水準。供應商依公司之需求預測作長期生產規劃。依需求變動及生產變動更新需求。,及時化生產系統,67,推行JIT之要素3,採購部門將設計變更及未來新零件的需求告知供應商。供應商
30、調整其生產、運送計劃以滿足公司之更新排程。供應商將零件以少量多批方式送至公司。進貨零件皆應有高品質而不需檢驗。,及時化生產系統,68,推行JIT的障礙,管理者不願意承諾。員工和管理者沒有合作精神。改變一個組織的文化相當困難。供應商可能會基於以下的理由反對：買方或許不願意承諾必要的資源，來幫助供應商適應 JIT。對於買方來說，長期契約或許履行不易。批量小、交貨頻繁也許會很困難，尤其是供應商擁有許多其他仍使用傳統系統的買方。品質管制的負擔轉由供應商負責。買方持續 JIT 系統的改善，將產生頻繁的工程變更。,及時化生產系統,69,JIT系統的效益1,降低存貨水準降低需求空間改進生產品質減少前置時間增
31、加生產彈性,及時化生產系統,70,JIT系統的效益2,使生產流程更為順暢增加生產水準作業人員參與解決問題促進與協力廠商的良好關係降低間接勞力的需求,及時化生產系統,71,服務業的精實系統,維持一致的高品質 設施負荷均勻 標準化工作方法 緊密的供應商關係 彈性勞動力,自動化 預防維修 拉式物料流程 生產線流程,及時化生產系統,72,個案研討速食店的JIT,維持一致的高品質 設施負荷均勻 標準化工作方法 緊密的供應商關係 彈性勞動力,自動化 預防維修 拉式物料流程 生產線流程,及時化生產系統,73,JIT實行的議題1,組織考慮JIT系統的員工成本Problem-solvingLost some a
32、utonomy(little or no safety stocks)合作與信任Scheduling，expediting and improving productivity lower-level personnel 薪資系統與員工分類JIT vs.Production volumeManagements flexibility vs.Union,及時化生產系統,74,實行的議題2,程序考慮 Cellular design costly存貨和排程 主生產排程穩定性 生產整備Small lot sizes vs.large number of setups採購與物流Small shipments of purchased items vs.geographic dispersion of suppliers,
