深溝滾珠軸承之精密熱間鍛造製程模具磨耗與不良品分析

黃忠義(Chung-Yi Huang)

指導教授 ： 傅尹坤

國立中央大學/工學院/機械工程研究所碩士在職專班/碩士(2015年)

摘要

深溝滾珠軸承在工業應用及生活應用都處處可見，舉凡工具機、腳踏車、汽車及機車等都可以見到它的存在可見使用用途廣泛。所以軸承是常考量用大量生產的方式作成軸承，常見軸承生產方式是使用棒材、管材及鍛造件配合切削加工來達到所需要型號大小尺寸，不僅要準備許多尺寸的原材料外，過程中需要浪費許多材料，另一種方式是以熱間鍛造配合滾壓加工製作成軸承單體，與棒管材配合切削加工方法相比熱間鍛造加上滾壓加工更能達到節省材料的目的並維持軸承品質水準。在汽車、航太、軍事、醫藥設備等產業，失效模式分析(FMEA, Failure Mode & Effects Analysis)是一種常用在設計開發與問題之預防分析方法，能有系統化的預測系統內可能引起失效之因素，並對產生失效現象因素解釋，評估各種發生之可能性及造成之原因，並選出關鍵影響因素，事先擬定解決對策方案，管制追蹤改善錯誤的執行，以便對所預測可能出現之失效與故障，先做好防範措施，減少產品使用風險與不確定性。故此文章將介紹業界完整的一套熱間鍛造流程包含熱間鍛造機、球狀化退火爐與冷間滾壓加工機，並且分析各製程生產過程中產生不良品的現象、原因與解決方法，文章中有冷間滾壓加工製程舉例不良品解決方法是需要透過前製程(如熱間鍛造機)改良才得以解決。

關鍵字

軸承 ； 熱鍛

並列摘要

Deep groove ball bearings are the most common machine elements and widely used in many fields of industries such as machine, bicycle, automotive and motorcycles.
There are mainly three methods for bearing ring production and the starting shapes can be in the configuration of rods and seamless tubes. Because of rods and tubes methods are used as raw material and the ring form is given by machining processes, so that the ratio of the waste material is high in forging process. At the end of turning operations the material waste is around 35% of the initial weight. In the third method, ring form is given by hot forging and cold rolling processes and the waste ratio decrease down to 7%.
The complete hot forging process consists of hot forging, spherodizing heat-treatment, sandblasting and cold ring rolling process. The aim of the study is to investigate the tooling wear and defects in hot forging process. The major cause of defect formation and possible remedies are proposed in the precision hot forging and cold ring rolling processes with validated experimental results.

參考文獻

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