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Huang Shengcai, Zhengzhou Research Institute of China Aluminium Corporation: On the occasion of the second technical discussion meeting for employees held at the electrolysis plant, I would like to briefly share with all leaders and colleagues some of the experiences and insights I have gained from my daily work. Please feel free to offer any criticism or suggestions if there are any mistakes in what I say. During the failure period of the electrolyzer, by analyzing the measurement data, it is possible to identify the location of the failure in a timely manner. By strengthening maintenance efforts, the rate of failure can be effectively reduced, thereby extending the lifespan of the electrolyzer. 1. By measuring the temperature of the steel window, it is possible to identify the areas where the side carbon blocks are damaged, allowing for timely corrective actions to be taken. When the temperature of the steel window is below 350°C, the furnace sidewall is still present at this time. At around 400°C, there is basically no furnace wall left, only carbon blocks on the sides. When the temperature reaches 450–500°C or higher, there are no more lateral carbon blocks; the steel areas in those zones often turn red, and close attention must be paid to such areas along with enhanced maintenance. II. Through long-term measurements of the pressure drop at the bottom of the furnace, it is possible to determine the degree of aging and damage at that location, as well as the age of the electrolyzer. Generally, the pressure drop at the bottom of a newly installed furnace is around 300–350 mV (except in cases where new energy-saving materials are used). Over time, this pressure drop gradually increases, reaching levels of 400 to 450 mV. For example, in Buildings 5 and 6, the pressure drop at the bottom of the furnaces is around 410 mV, and the age of these electrolyzers is approximately 1700 days. When the pressure drop at the furnace bottom exceeds 500 mV, it indicates that the aging and damage at the furnace bottom are quite severe ； For North 6#, the bottom pressure drop of its furnace reached 500 MV, and its cell age was over 2000 days. III. Measurement of damaged grooves: Once an electrolytic holder is identified as having damaged grooves, a comprehensive measurement of it must be carried out. In large electrolyzers, due to the large area of the furnace bottom, it is difficult to conduct a thorough inspection. To narrow down the area to be checked, the cathode current distribution and the temperature of the furnace bottom shell can be measured in order to make an initial assessment of the location of any damage. The cathode current distribution can be measured using a measuring rod made of copper; the actual current distribution value is obtained by multiplying the voltage drop measured directly across each cathode busbar by its corresponding correction factor. The arithmetic average of these values, along with the establishment of appropriate ranges, helps determine whether the distribution is normal or abnormal. The temperature of the furnace bottom tank shell is measured using an infrared thermometer; under normal conditions, this temperature should not exceed 100°C, and any value above that indicates an abnormality. IV. Improvements and innovations in measurement work: Previously, the furnace bottom pressure drop was measured by drilling holes in large areas, which not only disrupted the material and energy balance of the electrolyzer but was also time-consuming and labor-intensive. Later, it was found that since the resistance of the molten aluminum is very low, the resulting voltage drop is also minimal and can be ignored. We adopted the method of measuring the furnace bottom pressure drop at the direct aluminum outlet, which accurately reflects the magnitude of the furnace bottom pressure drop while saving labor and time. In our future work, we will continue to learn and explore ways to further improve our operational skills. We will work hard to ensure the stable, efficient operation of the electrolyzers, thereby making a proper contribution to our experiments related to low voltage and low efficiency.