鋼鐵製程分為煉鋼與軋鋼兩階段，訂單導向之鋼鐵業的兩階段製程的生產規劃，先決定軋鋼產品的「切割規劃」，再排定軋鋼階段的軋鋼排程規劃，最後反推至煉鋼階段的排程規劃。所以鋼胚經過軋鋼所得未切割鋼材之「切割規劃」是鋼鐵業生產規劃的基礎。本研究在發展實務觀點之有效的訂單導向鋼鐵廠「切割規劃」模式，能快速獲得績效良好的「切割規劃」解。其中，特殊規格的鋼材不應有庫存，唯獨常用的規格因為續獲訂單的可能性高，才允許庫存。鋼材切割規格
組合問題須同時決定若干個最佳規格組合以及每個規格組合對應的重複切割次數（生產量）以滿足各種規格的訂單需求，所以此問題本質上係非線性，且隨著問題規模擴大將更難求解。因此本研究提出一個四階段的「切割規劃」模式，將複雜的問題分階段求解，配合限制規劃軟體可大幅縮短求解時間又能兼顧求解的品質。一鋼鐵業的實例將用以驗證四階段規劃模式的求解速度與績效。

From practice perspectives, this paper proposes a four-stage planning model for solving the production scheduling problem for steel process with the objective to minimize the total inventory among the popular product, in which the demands of the popular and the special products should be satisfied. As the typical way to solve the considered problem involving simultaneously determining the pattern of product specification and the repeated cutting times for the corresponding pattern, the considered problem is quite complicate and carries the non-linear feature. The four-stage planning model efficiently solves these two categorical variables separately to reduce the complexity. A demonstrative example is also provided, which will be solved by the proposed model.