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On the Experience of Blast Furnace Overhaul Chang Quansheng Blast furnace overhaul is a periodic task for ironmaking enterprises, and the quality of such overhauls directly affects the service life of the blast furnace as well as the economic efficiency of the enterprise. Therefore, ironmaking enterprises must pay great attention to blast furnace overhauls. Based on my extensive experience in organizing major blast furnace overhauls, I would like to share the following insights. I. Thorough planning and adequate preparation are necessary. Although major repairs to blast furnaces occur on a regular basis, the complexity of these tasks and the wide range of aspects involved mean that the scope of repairs varies greatly depending on the production conditions and equipment performance at different stages of the furnace’s life cycle. Therefore, a detailed plan must be developed prior to the major overhaul, based on a thorough inspection of the wear and damage to various equipment components in the blast furnace. These include the maintenance project plan ； Equipment renewal plan ； Technical transformation plan ； Construction material plan ； Plans for the processing of spare parts and the acquisition of equipment ； The construction schedule must be formulated after comprehensive consideration of the blast furnace system’s production capacity, equipment condition, weather conditions, and available construction resources, in order to choose the best option; it is not possible to proceed without proper preparation. II. A rigorous construction plan design is necessary. In the overhaul of blast furnaces, various conditions are subject to limitations, such as those related to the site and the coordination between different processes. It involves multiple specialties working together, and there are certain connections and coordination requirements between different processes as well as between different specialties. Additionally, due to differences in construction equipment, the construction methods also vary. Therefore, before commencing construction, it is essential to develop a thorough construction plan. This plan should include strategies for shutting down the furnace, plans for demolition and installation, and in particular, methods for dealing with the layers of dead metal inside the furnace. It is important to make full use of the input of all stakeholders, to incorporate opinions and suggestions from various sources, to draw on past experiences and lessons learned, and to compare and optimize different options repeatedly, so that the final plan is scientific, reasonable, as well as advanced and feasible. III. Take advantage of major overhauls to carry out as much expansion, renovation, and technological improvement as possible. The cycle for overhauling blast furnaces is relatively long (usually 5–8 years). During such a long production period, scientific and technical advancements continue to occur in various fields, including materials, processes, and equipment, both within the same industry and across different specialties. Meanwhile, the blast furnaces themselves accumulate experience and lessons throughout their operation. Due to the special requirements of continuous production, it is difficult to introduce and implement advanced technologies in a timely manner. In fact, experiences from private enterprises show that the auxiliary equipment designed for small and medium-sized blast furnaces in the past was rather conservative; there is still significant potential for improvement in areas such as fans, hot air stoves, and dust removal systems. It is absolutely no problem to expand the blast furnace by 1.3 or 1.5 times using a major overhaul. Therefore, making full use of blast furnace overhauls for capacity expansion and technical upgrades represents an excellent opportunity. The experience of many ironmaking enterprises shows that such expansions lead to significant economic benefits in terms of increased production, and these benefits are quite substantial. The Linzhou Modern Ironmaking Technology Center has a comprehensive \"Construction Plan for Blast Furnace Installation,\" which includes specific construction methods for each task. Note: Chang Quansheng was formerly an engineer at the Linzhou Company in Henan Province, as well as the manager of the machinery repair workshop; he possesses extensive experience and expertise in the major repairs and expansion projects of blast furnaces.