blow air thermocouple structure theory is that there is a certain gas path between the armored thermocouple and protection tube. Users need input inert gas with certain pressure to eliminate or reduce the gas penetration under the high- temperature, high- pressure conditions. If you add tantalum, it will increase the suction characteristics of blowing-type thermocouple and extending the life of armored thermocouple. It is a key temperature sensor for ammonia completed device.