運用六標準差方法改善馬達異音問題

在今日蓬勃發展的服務業經濟時代裡，提供顧客高品質與快速的服務已經廣泛地被許多世界級的公司視為達成卓越企業績效的重要方法。格蘭富公司(以下簡稱個案公司)是目前全球居於領導地位的泵浦製造商之一。雖屬一般定義的傳統產業，但企業經營並不傳統，現在正應用各種現代化經營理念與經營技術，希望能成功的發展、製造、以及向全球銷售最高品質的泵浦與唧水系統，並為提高生活品質及創造一個健康的環境。本研究個案旨在探討個案公司因OEM客戶報怨其馬達異音問題之品質問題，為了有效解決客戶問題，個案公司利用六標準差DMAIC模式來進行馬達異音軸承生鏽問題之改善。藉由六標準差改善方法與邏輯，期盼對作業流程之改善能有卓越的成效，同時也可以提昇企業競爭力。本研究首先透過顧客的聲音及市場資料的回饋將其問題定義清楚，接著將其轉換成關鍵品質特性之後，再透過高階流程圖(SIPOC)及量測系統的分析來驗證問題。之後再透過分析工具的使用，來進行要因分析，期望藉由分析以得到確實影響流程輸出的主要輸入原因。最後，個案公司發現馬達凡立水製程是影響軸承生鏽的關鍵輸入製程，從小規模的實驗結果中得出在凡立水製程中，因馬達定子加熱溫度之不穩定，以導致於凡立水並未完全乾燥，最後因環境中濕度變化之影響與催化下，讓軸承滑脂與凡立水殘留之酸性氣體相結合產生化學變化，最後侵蝕軸承。本研究針對分析結果提出馬達定子乾燥溫度之改善方案，其改善後之效益為馬達退貨率從114台/年，降至0台/年，最後節省費用約為新台幣2仟8佰多萬元以及客戶平均一年約6,000台之銷售數量，銷售額約為新台幣9仟多萬元。此外，本研究透過流程管理計劃，確實將凡立水製程中所必須注意之控制點以圖面之方式來防止問題之再發。

關鍵字

六標準差方法；馬達軸承

並列摘要

In current economic time where service business is booming, providing high quality and quick service to customers has become one important way to achieve business excellence by many world-class companies.GRUNDFOS Group is one of the leading pump manufacturers in the world. Although it is defined as a traditional industry, Grundfos implement modern concepts and technologies to make it everything but traditional in business management. Grundfos aim to develop, produce and sell highest quality pumps and booster systems to the world in order to create a healthy environment and bring up the living quality for human beings. The purpose of this study is to investigate how Grundfos provide an effective solution to an OEM customer who has a complaint about motor noise in the pump. Grundfos run a project of quality improvement for rusty bearing noise from the motor by using Six Sigma DMAIC approach. By applying the logic and the improving method from Six Sigma, Grundfos anticipate an excellent effectiveness in the working process, and therefore increase the company’s competitive edge in the business. The investigation shows that from the start, Grundfos define the issue of the complaint clearly through an understanding of customer voice and an analysis of feedback from the market. The issue is then transformed to a critical to quality (CTQ). Process mapping (SIPOC) and data from measuring system are used to verify the issue. By using analyzing tools for root cause analysis, the key input which really affects the process output is expected to be found. Based on the results from above analysis, an action to improve the heating temperature of motor stator is implemented with an aim to ensure the motor stators are totally dry and hardened in the lacquering process. This action solves the rusty issue completely. As a result the motor return rate drops from 114 units per year to 0 unit per year, which is a dramatic saving for Grundfos as they would have to pay a credit cost around NTD28 million and sales order around 6,000 units per year (NTD90 million) if this quality issue could not be resolved successfully. In order to prevent the same issue from happening again, Grundfos make a process management plan and use drawings to indicate all control points in the lacquering process.

並列關鍵字

motor bearing ； Six Sigma Approach ； DMAIC ； SIPOC

參考文獻

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