- 學位論文
精實生產與供應鏈的整合模式 – 以福特汽車為例
An Integrated Model of Lean Production and Supply Chain - Case Study from Ford Motor
摘要
美國通用汽車(GM)自1931年取代福特汽車成為全球最大汽車廠之後，持續稱霸世界車壇超過70年。直到2008年一場全球的金融風暴擊垮美國車界，GM的銷售量掉落到豐田(Toyota)的後面。著名的精實生產(Lean Production)正是豐田生產系統(TPS)創作下的產物，不但造就豐田汽車令業界驚嘆的成功故事，同時也使得其他擁有相似系統的日本汽車一樣的來勢凶凶。於是美國三大車廠(Big3)和其他企業自1990年代開始爭相模仿TPS的精實生產，試圖能藉此提振其市場銷售及競爭力，雖然三大汽車都各別花了超過10年以上的時間學習，卻仍無法達到豐田汽車的近似水準。我們不禁要問，若精實生產的推動是造就豐田汽車成功的重要因素，那為何其它眾多競爭者儘管努力的學習與應用卻還是無法與之抗衡？似乎在TPS的內涵中仍存在著某些難以模仿的特殊核心能力等待去探索，而這些特殊的核心能力也正是目前三大汽車和其它企業對精實生產仍然持保留態度及躊躇不前的原因。 為了回應上述的問題 - "為何三大汽車雖然推行了精實生產的改善手法卻仍然無法達成預期的銷售成長？"，本研究試圖找出明確答案 - "到底三大汽車存在著什麼樣的核心問題？哪些行動方案才能幫助三大汽車提振其市場銷售？"；另外，本研究也試圖發掘TPS的精實生產具備哪些核心能力能促使豐田獲致持續不斷的成功。有鑑於此，本研究將以整合模式的方式來呈現：除了使用案例推論(Case-Based Reasoning)的研究方法搭配四步驟的問題解決流程來印證TPS如何藉著它的精實供應鏈工具 - 價值流圖(Value Stream Mapping)在成本降低，品質提昇和交期縮短方面的持續改善來鞏固其核心能力。另外，也以一般問題解決流程的四步驟結合四個限制理論(Theory of Constraints)的邏輯樹圖進行案例研究來協助三大汽車發掘其根本問題與對策，以突破其持續市場蕭條的困境。 另一個待回答的問題 - "限制理論(TOC)是否能有效解決這類複雜的管理策略問題？"，本論文從TOC的案例研究，不但明確地回答上述問題，而且還進一步彙總提供後續研究及問題解決生手一些實用的問題解決建議。另外，透過福特汽車的價值流案例研究，從現況圖到未來圖的分析過程，所有的衡量指標都朝向正向趨勢，也印證價值流的持續改善的確幫助TPS達成其精實供應鏈：最佳品質，最低成本和最短交期的長期目標，並進一步強化其核心能力。 本論文的最大目的除了印證價值流在改善供應鏈方面的價值及其在精實生產持續改善方面的貢獻外；同時也提供具體的問題解決流程配合限制理論的運用來協助企業有效的找出其核心問題和具體對策。 最後，本論文整理幾項對學術與企業界的價值和貢獻如下: 1. 透過對核心能力的探討區別精實生產與TPS的最大差異來幫助推動者作有價值的改善。 2. 提供以核心企業流程作為改善重點的價值流案例來有效取代傳統冗長周期的供應鏈改善。 3. 整理具體的遵循原則協助企業快速有效的推動價值流改善。 4. 提供明確的問題解決流程結合價值流改善來幫助生手提升問題解決能力。 5. 運用限制理論搭配一般問題解決流程也能幫助學生有效的改善管理策略問題。 6. 綜合TOC的問題點與限制提供後續學者做進一步研究的參考。
並列摘要
The famous Lean Production (LP), a brainchild of Toyota Production System (TPS) has played a significant part in Toyota’s success story. The Big 3 (the three big motor companies in U.S.) and other enterprises have learnt from the Toyota’s production system in an attempt to become more competitive. It took more than ten years for the Big 3 to learn TPS or LP related production strategy, but without the same result of Toyota Co. However, if the development of LP is the key to Toyota’s success, why have its competitors struggled despite adopting similar principles? It seems that there is a special core competence within Toyota Motor Company that is not fully understood as yet. In order to address the questions: “Why the Big 3 failed to achieve their expected growth despites their adoption of lean management?”, "are there any comprehensive steps for the Big 3 to turnaround their current situation?” and “how Toyota can continuously and consistently achieve its dramatic success through its core competences?”, this study develops an integrated model using the Case Base Reasoning (CBR) approach. The methodology links four-step problem solving process (PSP) to demonstrate how Toyota use its Lean Supply Chain (LSC) tool – the Value Stream Mapping (VSM) to achieve its core competences through continuous cost reduction, quality enhancement and lead time shortening. Moreover, we also use the four-step PSP to link up the Theory of Constraints (TOC) logic tree diagrams to discover the root causes and countermeasures for the problem. This study illustrates the VSM approach using a case study from the Taiwanese Ford motor company. Through the VSM development from Current State Map (CSM) to Future State Map (FSM), it is proved that all measurable indicators are on the right trend, showing VSM supports LSC on cost reduction, quality enhancement and lead time shortening through P-D-C-A continuous improvement cycle. The major purpose of this dissertation not only shows the value of VSM as a supply chain tool for implementing LP through case study and CBR process application, it also provides industrial insight for those hesitant companies and novices to follow up four-step PSP and link with the deployment of TOC logic tree diagrams to effectively find out their core problems and comprehensive actions. This study provides managerial insights and contributes to both academic and industrial fields in following areas: 1. Identifies the major differences between LP and TPS through core competence review and the comparison; it provides valuable insights for those companies trying to apply LP. 2. Identifies the weakness of traditional supply chain and suggest a LSC tool such as VSM. 3. Provides the basic principles to implement VSM effectively through a case study. 4. Provides comprehensive PSP linking with VSM development for novices (students) to improve their problem solving skills. 5. Demonstrates the improving process for novices (students) to apply TOC logic tree diagrams. 6. Summarizes some issues and limitations for future research.