Factor analysis and yield optimization of a billet manufacturing process: A case study.

摘要

There is a growing demand for iron and steel productions due to their fundamental role in various sectors of industry. Thus, iron and steel manufacturing plants thrive to increase the efficiency of their productions and increase the yield. One of the main challenges facing billet manufacturers is providing raw materials especially since iron ore is not accessible to many. Thus, various types of iron scrap are utilized as the raw material. Also, specific Ferro-alloys are added to the molten iron scrap in the induction furnace in order to increase the quality of the final yield. Although there are many variables affecting the final yield in a continuous casting process, such as facility layout, thermal conditions of melting iron, casting machine, cooling and cutting procedure, this study is focused on how composition of materials can affect the tonnage of final yield.;This research focuses on investigating two major points. Firstly, the researcher investigates any possible correlation between various types of iron scrap and the percentage of final yield. Secondly, the researcher studies if there is any relationship between various levels of Ferro-alloys and the final yield percentage. Raw material profile measurements were gained over one year in the billet manufacturing factory under study, including a detailed list of all Ferro- alloys added to various types of iron scrap in induction furnace as well as the various types of iron scrap utilized with their percentage in the total used raw materials.;The researcher applied statistical analysis via multivariate regression analysis considering various types of iron scrap as multiple variables for conducting regression in the first part of the methodology and various levels of Ferro- alloys as multiple variables for doing regression analysis in the second part. In both, final yield percentage is considered as the response (dependent) variable. Statistical analysis was used to investigate, theoretically, the effect of various variables on the product pattern including yield. In addition, process analysis was done in order to figure out various statistical features of the process. The final results show that certain composition and percentage of certain iron scrap types utilized as raw materials have a significant effect on the process yield. However, the results show that the Ferro- alloys levels are not significant predictors in explaining the variations in the yield percentage.