- 學位論文
安全歧管鍛造模具應力分析
Stress Analysis of the Forging Die for an Air-Bag Manifold
摘要
目前的汽車安全氣囊用歧管為相關產業重要的零件，因此產品的品質會影響組裝與使用，然而為減少模具異常破裂的損耗，以減少模具成本支出及出貨交期、品質的穩定，因此本文採用有限元素分析軟體DEFORM-2D，在不增加原模具最大尺寸及模具的成本設計下，模擬凸緣整形製程模具可承受之應力，研究分析一體模仁與分割模仁及藉由改變分割位置、預應力環干涉量等參數，模擬模具應力分佈狀況，做為後續改善模具異常破裂所造成不必要的成本浪費及換模工時的重要依據。 研究後有以下結論： 不給預應力環：不給予預應力環時，各組資料顯示分割往下2mm張應力<原設計分割位置<分割往上2mm已經可以證明分割往下移是有助於降低模具張應力，以減少模具破裂機率。 單層預應力環：當分割位置改變後分割越往上移時預應環給的預壓力越好，但是在成形時則是分割越往下移張應力越小，表示分割往上移時雖然得到較大預壓但是相對的在成形時也承受了更大的張應力，另一方面可以證明成形時張應力是很大的。 雙層預應力環：加上外層預應力環對於整體模具應力影響會比單層預應力環更為趨緩，然而分割位置的改變，在成形前的趨勢並不明顯，然而成形中趨勢會較為明顯，其中以模仁往下分割的條件會使張應力的極值下降。 預應力環(束環)干涉量的增加是有助於降低模具張應力，然而2層以上的設計時，更需注意各環間的干涉量大小以達到最佳化設計。
並列摘要
Nowaday manifold that used on automobile air bag has became an important part in the related industries. Part’s quality will affect assembling and use. In order to reduse the tooling’s abnormal wearing, cost, lead time, and stable quality, the finite element analysis software Deform-2D was employed in this study. In order to not increase the maximum size of die and save the cost of die. Simulation the flanging to analyze the stress of die. This study is to analize the integral die, divisional die, and the simulating stress’ distrubution of the die that is caused by the dividing location and prestress’ interfering parameter. To meliorate the die because the abnormal crack of die could make the unnecessary costs and working hours. After study,this shiows: No offer prestress ring: under this status, each shows the result, the stress that is downward 2mm of divisional location < original design < upward 2mm. This can prove that downward the divisional location can help to reduce die’s stress and die’s cracking rate. Single layer prestress ring: when the divisional location is changed, the upward-moved division will give prestress ring a better prestress. But when forming, the downward will get a smaller stress. This tells that the upward division can get much more stress, oppositely, that stands a much bigger stress when forming. The other side, this can prove its stress is very huge when forming. Dual layer prestress ring: the additional outer prestress ring to the whole die will get postponed than the single layer prestress ring. The change of its divisional location is not clear before forming. That will be clearer when forming. Among them, the downward division will reduce its maximan stress. The additional interfering in the prestress ring will help to reduce die’s stress. However, over dual layer’s design, we need to care the interfering’s capacity among rings in order to get a good design. Keywords: manifold, die stress, finite element analysis, Optimization of forging die.