旋轉鍛造亦稱擺輾鍛造,是一種結合滾壓和鍛造的加工方式,其成型所需負載較傳統鍛造低,並同時擁有鍛造的優點,如鍛件表面光滑、減少材料浪費與可有效降低加工時間等。本文將研究以二階段旋轉鍛造成型傘形齒輪,並利用有限元素軟體Deform-3D進行模擬分析,以3因子3水準全因子共27組模擬組數,透過回歸建立二階含交互項之多項式預測模型,求得在良好填充率下,軸向成型力峰值最小化之最佳化錐形胚料設計。;Orbital forging also called rotary forging, is a combination of rolling and forging processing methods, which required lower load than traditional forging. It has many advantages, such as forging smooth surface, which can effectively reduce material waste and reduce processing time and so on. This paper proposes a new procedure for forming bevel gear in two steps of rotary forging. The FEM simulation model of cold rotary forging is established under Deform-3D software environment. Regression analysis simulation results to obtain the tapered billet design optimization in minimizing the peak axial force and good fill rate.