近幾年來,隨著綠色能源等環保意識的高漲,人們越來越重視節能減碳,世界各地因而都興起了一股騎單車的風潮。於此風潮之下,自行車不僅只是交通工具,還發展至休閒運動及競賽領域,也因為騎自行車風氣盛行,使自行車研發及創新工作不斷的精益求精,而輕量化的設計就成為一種趨勢,且也能滿足單車騎士或運動選手多元的需求。 對企業而言,要在競爭激烈的環境中脫穎而出,就必須有獨特性(例如輕量化)的產品才能滿足消費者的需求。在自行車的市場中,重量越輕其價值及售價也越高,因此,原先的鐵製避震器上叉管(Upper Tube)逐漸發展至進階的鋁製避震器上叉管,且鋁管厚度也越抽越薄。 個案公司在產品開發週期的各階段,都會對上叉鋁管進行嚴謹的品質檢驗及測試,可是在量產階段的成品抽樣測試中,還是會發生上叉管失效的問題。失效模式與效應分析(Failure Mode and Effects Analysis, FMEA)是一種可於事先防範產品發生失效以避免其失效造成影響的分析方法,本研究透過失效模式與效應分析的實施,調查上叉鋁管29項風險失效模式對產品品質影響的程度,依其重要性排序,並一一擬定相對應的改善對策。經過調查顯示,上叉鋁管製程中失效模式排序前五項為:機械性質不良及殘留內應力、硬度不均、晶粒過大、晶粒異常、退火不均,個案公司應該立即針對這些失效模式擬定處理方式,以降低產品進入市場後失效所帶來的風險,也確保個案公司對生產避震前叉做出品質異常事前預防,並降低公司損失。
In recent years, with the rising awareness of environmental protection, there is a surge demand of bicycle all over the world. Under this trend, bicycle is not only a transportation tool but also a tool for sports and leisure use. Hence, how to make a lighter bicycle become an important issue for the ordinary and sports cyclists. In the highly competitive bicycle market, the lighter the weight of the bike the higher price of it, therefore, the original iron-made upper tube of the suspension part has been replaced by the aluminum-made upper tube gradually and progressively and the thickness of the tube has been thinner and thinner. Case company has applied rigorous quality inspection practhe manufacturing process of the upper tube, however, during the inspection process of the final product, there still has some defective problems. Failure mode and effects analysis (FMEA) is a proactive method that can be used to prevent defective product occurnces in order to avoid subsequent consequences by systematic analysis of the failure modes and their impacts. This study thus applies the FMEA to the manufacturing process of the upper tube of the suspenstion part of the case company to investigate the 29 failure modes and their associated effects and prioritize them by their importance. In this study, the top five failure modes identified are: poor mechanical properties and residual stress, uneven hardness, grain size is too large, abnormal grain, and uneven annealing. Case company should immediately resolve these failure modes to reduce the risk of failure of the product and prevent and reduce the company's future potential loss.