准时制与精益生产方式.ppt

1、Fang Aihua Wuhan University,Lean Production,JIT & Lean Production Systems 准时制与精益生产方式,Fang Aihua Wuhan University,2,Just-in-time Production Systems,Lean Production Defined The Toyota Production System Lean Implementation Requirements Lean Services,LP的定义 丰田生产系统 LP的实施条件 精益服务,Fang Aihua Wuhan University

2、,Lean Production Defined,精益生产方式的定义,Fang Aihua Wuhan University,Lean Production 定义,Lean Production can be defined as an integrated set of activities designed to achieve high-volume production using minimal inventories (raw materials, work in process, and finished goods) Lean Production also involves

3、the elimination of waste in production effort Lean Production also involves the timing of production resources (i.e., parts arrive at the next workstation “just in time”),LP: 利用低库存获得高产量的一整套活动. LP:努力消除浪费 LP:生产资源的时间编排(JIT),Fang Aihua Wuhan University,Pull System拉动系统,Here the customer starts the proces

4、s, pulling an inventory item from Final Assembly,Then sub-assembly work is pulled forward by that demand,The process continues throughout the entire production process and supply chain,Fang Aihua Wuhan University,生产方式的演变,手工生产方式 大量生产方式 精细生产方式 大规模定制,法、德（19世纪） 奔驰公司 美国（20世纪上半叶） 福特公司 日本（20世纪下半叶） 丰田公司,Fan

5、g Aihua Wuhan University,精细生产方式Lean Production,美麻省理工学院国际汽车项目组的研究人员给日本汽车工业的生产方式起的名称。 与大量生产方式相比， 只需一半的(人员、场地、投资) 产出质量更高、品种更多的产品,Fang Aihua Wuhan University,Some statistics from 1986,Framingham (GM) 40.7 hours 130 defects 2 weeks,Toyota Takaoka 16 hours 45 defects 2 hours,A comparison of 1) assembly ho

6、urs 2) defects / 100 cars 3) average inventory levels,Fang Aihua Wuhan University,5,The Japanese Approach to Productivity精益生产方式的产生背景,Goal of full employment in the post WWII period. Government (MITI) supported improvement of targeted industries. Imported technologies. Efforts concentrated on factory

7、 floor. Quality improvement focus,全民就业的目标 （实业建国） 政府扶持计划选定的产业 引进技术 （而非自主开发） 注重生产一线 持续质量改进,Fang Aihua Wuhan University,Two Philosophies核心理念,Elimination of waste Respect for people.,消除浪费 尊重人,Strive for Simplicity(another US Textbook) Always use simple approaches Simple designs Simple control Mistake-pr

8、oof processes,Fang Aihua Wuhan University,6,WasteOperations生产中的七种浪费,(1) Waste from overproduction (2) Waste of waiting time (3) Transportation waste (4) Inventory waste (5) Processing waste (6) Waste of motion (7) Waste from product defects,(1)过量生产的浪费 (2) 等待时间的浪费 (3) 运输的浪费 (4) 库存的浪费 (5) 工序的浪费 (6) 动作

9、中的浪费 (7) 产品缺陷的浪费,Fang Aihua Wuhan University,The “Rocks in the Stream” Concept,Production Problems,Water Level (Inventory),Rock (problem),Boat (company operations),Fang Aihua Wuhan University,Lowering the “Water” Level,Production Problems,Inventory Reductions,CRUNCH!,Fang Aihua Wuhan University,Step

10、 Two - Deal with Exposed Problems,Production Problems,Inventory Reductions,Process Improvement of Production Problem,Fang Aihua Wuhan University,Step Three - Continue the process,Production Problems,Inventory Reductions,Identification of new problem area,Fang Aihua Wuhan University,What is Inventory

11、 in a Lean Production View?,A potential form of waste (when value is not being added) A useful measurement to tell how well the system is working A useful tool to help identify critical uncertainties and production problems,Fang Aihua Wuhan University,The seven elements that address elimination of w

12、aste消除浪费的七种方法,Focused factory networks Group technology Quality at source JIT production Uniform plant loading Kanban production control system Minimized setup times,集中工厂网络 成组技术 源头质量控制 JIT生产 均衡生产负荷 看板控制系统 最小化调整时间（换模）,Fang Aihua Wuhan University,7,Focused Factory Networks 集中的工厂网络,Coordination,System

13、Integration 整合系统,小型专业化工厂 Small specialized plants,Fang Aihua Wuhan University,8,Group Technology成组技术,Departmental Specialization(Job shop) 部门专业化,Saw,Saw,Lathe,Press,Press,Grinder,Lathe,Lathe,Saw,Press,Heat Treat 热处理,Grinder,Saw 锯,Grinder 磨,Lathe 车,Press 冲压,Fang Aihua Wuhan University,9,Group Technol

14、ogy成组技术,Group technology cells 成组技术加工单元,Press,Lathe,Grinder,Grinder,A,2,B,Saw,Lathe,Saw,Lathe,Press,Lathe,1,Saw 锯,Grinder 磨,Lathe 车,Press 冲压,Heat Treat 热处理,Fang Aihua Wuhan University,Kanban Production Control Systems看板控制系统,Kanban: a signaling device to regulate JIT flow.,看板: 一种控制物流品种与数量的标识性的工具。,Fan

15、g Aihua Wuhan University,Kanban Production Control Systems,Storage Part A,Storage Part A,Machine Center,Assembly Line,Material Flow Card (signal) Flow,Withdrawal kanban,Once the Production kanban is received, the Machine Center produces a unit to replace the one taken by the Assembly Line people in

16、the first place,This puts the system back were it was before the item was pulled,The process begins by the Assembly Line people pulling Part A from Storage,Production kanban,Fang Aihua Wuhan University,16,Calculating the Number of Kanbans Needed 计算看板数量,Setting up a kanban system requires determining

17、 the number of kanbans (or containers) needed. Each container represents the minimum production lot size. An accurate estimate of the lead time required to produce a container is key to determining how many kanbans are required.,确定看板(或容器)数量 每个容器代表最低的加工批量 关键是须要尽可能精确地估计生产一箱零件的时间,Fang Aihua Wuhan Unive

18、rsity,17,The Number of Kanban Card Sets, k看板的数目,k = Number of kanban card sets d = Average number of units demanded over some time period L = lead time to replenish an order (same units of time as demand) S = Safety stock expressed as a percentage of demand during lead time C = Container size,k = 看板

19、数量 d = 平均需求量 L = lead time 提前期 S = 安全库存(用提前期中需求量的比例形式表示) C = 容器的大小,Fang Aihua Wuhan University,21,Respect for People尊重员工,Maintain level payrolls Cooperative employee unions Subcontractor networks Bottom-round management style Quality circles (Small group involvement activities),维持稳定的工资 合作性的工会 分包商网络

20、现场管理（基层委员会+小组） 质量小组,Fang Aihua Wuhan University,JIT Requirements JIT的前提条件,Design Flow Process 设计流程（科学、连贯） Total Quality Control 全面质量管理（自觉、自动检测） Stabilize Schedule 稳定的计划 Kanban-Pull 看板拉动 Work with Vendors 与供应商合作 Reduce Inventory more 进一步减少库存 Improve Product design 改进产品设计（标准化、部件少）,Fang Aihua Wuhan Uni

21、versity,11,JIT PurchasingRequirements准时采购的条件,Reduced lot sizes Frequent and reliable delivery schedules Reduced and highly reliable lead times Consistently high quality levels for purchased materials,减小批量 频繁而可靠的交货 提前期压缩并且高度可靠。 保持一贯的采购物资的高质量。,Fang Aihua Wuhan University,12,JIT PurchasingSuppliers准时采购

22、供应商,Fewer, nearby suppliers Repeat business Support suppliers competitiveness Clusters of remote suppliers Limit competitive bidding to new parts Resist vertical integration Encourage suppliers to implement JIT purchasing,少量、近距离 重复业务 支撑供应商竞争力 使距离较远的供应商尽可能靠近 投标竞争仅限于新的零部件 反对垂直一体化 鼓励供应商也实施准时采购,Fang Aih

23、ua Wuhan University,13,JIT PurchasingQuantities准时采购数量,Steady output rate (a desirable prerequisite) Frequent deliveries in small lot quantities Long-term contract agreements with minimal release paperwork Deliver quantities variable from release to release but fixed for whole contract term,稳定的产出率,频繁的小批量送货,长期合同、减少日常文书工作,每次交货数量可变，但整个合同期的数量固定,Fang Aihua Wuhan University,14,JIT Purchasing-Quantities (Ctd)准时采购数量,Little or no permissible overage or underage of receipts Suppliers encouraged to package in exact quantities