OM-Chapter 13e-Lean system

JIT system: A system that organizes the
resources, information flows, and decision rules that enable a firm to realize the benefits of JIT principles.
Push and Pull Systems of Work Flow
Push method: A method in which production
of the item begins in advance of customer needs.
Example: A buffet where food is prepared in advance.
Just-in-time (JIT) philosophy The belief that
waste can be eliminated by cutting unnecessary capacity or inventory and removing non-value-added activities in operations.
Characteristics of Lean Systems
Line Flows and Automation
Line Flows: Managers of hybrid-office and
back-office service processes can organize their employees and equipment to provide uniform work flows through the process and, thereby, eliminate wasted employee time. Another tactic used to reduce or eliminate setups is the one-worker, multiple-machines (OWMM) approach, which essentially is a oneperson line.
Pull method of work flow Quality at the source Small lot sizes Uniform workstation loads Standardized components & work methods Close supplier ties Flexible workforce Line flows Automation Five S Preventive maintenance
Single-digit setup: The goal of
having a setup time of less than 10 minutes.
Characteristics of Lean Systems
Pull method of materials flow Quality at the source Small lot sizes Uniform workstation loads Standardized components & work methods Close supplier ties Flexible workforce Line flows Automation Five S Preventive maintenance
Uniform Workstation Loads
A lean system works best if the daily load on individual workstations is relatively uniform. Service processes can achieve uniform workstation loads by using reservation systems (e.g., scheduled surgeries) and differential pricing to manage the demand. For manufacturing processes, uniform loads can be achieved by assembling the same type and number of units each day, thus creating a uniform daily demand at all workstations. Mixed-model assembly produces a mix of models in smaller lots.
Lean Systems
Lean systems are operations systems that
maximize the value added by each of a company’s activities by paring unnecessary resources and delays from them.
Pull method of materials flow Quality at the source Small lot sizes Uniform workstation loads Standardized components & work methods Close supplier ties Flexible workforce Line flows Automation Five S Preventive maintenance
LP的起因
回国后先在一个车间试点,由订单拉动,后 工序向前工序发生产指令.遭到很大的阻 力,一年后获得成功,大野耐一从车间主任 提升为厂长,在全厂推行,到1963年全厂 实现准时化生产. 以后向协作厂推广,到 1973年基本形成一种全新的生产方式— —丰田生产方式. 73年爆发石油危机,丰 田公司一枝独秀,被证明是一种极具竞争 力的生产方式.
Pull method of materials flow Quality at the source Small lot sizes Uniform workstation loads Standardized components & work methods Close supplier ties Flexible workforce Line flows Automation Five S Preventive maintenance
Pull Method: A method in which customer
demand activates production of the service or item.
Example: A restaurant where food is only prepared when orders are placed.
Characteristics of Lean Systems
Small Lot Sizes
Lot: A quantity of items that are
processed together.
Setup: The group of activities needed to
change or readjust a process between successive lots of items.
Quality at the Source
Quality at the source is an organization-wide
effort to improve the quality of a firm’s products by having employees act as their own quality inspectors, and never pass defective units to next stage. One approach for implementing quality at the source is to use poka-yoke, mistake-proofing methods aimed at designing fail safe systems that minimize human error. Another approach for implementing quality at the source is a practice the Japanese call jidoka, and andon, which gives machines and machine operators the ability to detect when an abnormal condition has occurred.
Chapter 13
Lean Systems
精益系统
Toyota Production System (TPS)
Toyota Production System (TPS) is one of the most admired lean manufacturing systems in existence. They have a process of continuous improvement. Work is completely specified as to content, sequence, timing, and outcome. Services and goods do not flow to the next available person or machine, but to a specific person or machine. Employees are stimulated to experiment to find better ways to do their jobs. Improvements to the system must be made in accordance with the scientific method, under the guidance of a teacher, at the lowest possible organizational level.
LP的起因
到福特公司考察,发现美国的大批量加工 不适合日本国情. 日本的汽车市场上，品种多 战后日本资金严重短缺 日本资源贫乏，国土面积小 寻求适合自己的制造汽车的方式
LP的起因
劳动生产率 1:10 不是 1 个大个子美国人顶 10 个小个子日本人,而 日本肯定在什么地方存在大量浪费 质量差是浪费 库存量大是浪费 用工多是浪费 全部工作从消除浪费开始 首先向库存开刀 降低库存的最好方法是准时生产,全部生产活动 由订单拉动,思路正确但一时想不出好的方法. 在美国逛超市时无意中触发灵感,想出了好的方 法.
精益生Hale Waihona Puke Baidu体系
一个核心思想:
杜绝一切浪费 浪费定义：不产生价值的活动是无效的， 都是浪费。
两根支柱: 准时化： 在需要的时候，按需要的数量加工，不提前、 不过量制造 自动化：目的是保证质量 方法：给设备以人工智能； 人工装配线上工人有权停产。 一个工具:
看板管理
Characteristics of Lean Systems
Lean systems use the pull method of work flow.
Characteristics of Lean Systems
Pull method of materials flow Quality at the source Small lot sizes Uniform workstation loads Standardized components & work methods Close supplier ties Flexible workforce Line flows Automation Continuous improvement and Five S Preventive maintenance