A large-scale photovoltaic glass manufacturer needs long-term monitoring of high temperatures up to 1650°C in the hot zone of the melting furnace for ultra-clear rolled photovoltaic glass, while the components must resist erosion from alkali metal vapors. The original ordinary high-alumina Thermocouple Protection Tube suffer from insufficient temperature resistance and poor corrosion resistance, with an average service life of less than 48 hours. Frequent replacements not only increase operation and maintenance costs but also disrupt production continuity, creating an urgent demand for a temperature measurement protection solution tailored to such extreme working conditions.
Combined with the customer’s actual working conditions, customized 99.3% high-purity corundum thermocouple protection tubes are selected for the application. Manufactured from high-purity α-alumina via dense sintering technology, this product features a maximum temperature resistance of up to 1800℃ and can withstand even higher temperatures for short-term service. With extremely low impurity content (SiO₂ ＜ 0.1%), it effectively prevents contamination of photovoltaic glass melt. It also delivers excellent alkali corrosion resistance and thermal shock resistance, perfectly adapting to high-temperature radiation and periodic temperature fluctuations inside melting furnaces, and is fully compatible with the customer’s existing Type B thermocouples.
After application, the corundum thermocouple protection tubes operate continuously and stably in the hot spot areas of melting furnaces. Their average service life is extended to more than 6 months, over 30 times longer than that of the original high-alumina tubes. The temperature measurement accuracy is controlled within ±1.5°C, which effectively ensures the stability of the glass melting process and reduces the risk of thermocouple damage. It helps the enterprise save over 200,000 RMB annually in costs such as spare parts replacement and shutdown maintenance.
This case fully demonstrates the core advantages of corundum thermocouple protection tubes in high-temperature and strongly corrosive industrial environments. Currently, this product has been widely applied at all temperature measurement points of photovoltaic glass melting furnaces in this enterprise, and has been promoted to other leading enterprises in the same industry. It is suitable for various high-temperature working conditions such as glass melting furnaces, metallurgical smelting and special material preparation.
