What are the graduation numbers of thermocouples? What are their characteristics?
The indexing numbers of thermocouples are critically divided into S, R, B, N, K, E, J, T and so on. Among them, S, R, and B belong to precious metal thermocouples, and N, K, E, J, and T belong to low-cost metal thermocouples.
The characteristic of S index number is strong oxidation resistance, and it is suitable for continuous application in reducing and plastic atmosphere. The long-term application temperature is 1400℃, and the short-term application temperature is 1600℃. Among all thermocouples, the S index has the highest accuracy level and is generally used as a standard thermocouple.
2. Comparing R index number and S index number, the heat removal induced electromotive force is about 15% larger, and the characteristics of other thermocouples are basically the same.
3. The thermally induced electromotive force of B index number is very small at indoor temperature, so it is generally not necessary to compensate the wire for accurate measurement. Its long-term application temperature is 1600℃, and its short-term application temperature is 1800℃. It can be used in reducing or neutral atmospheres, and thermocouples with index B can also be used in a short period of time under vacuum pump standards.
4. The characteristic of N index number is strong high temperature oxidation resistance at 1300℃, long-term reliability of thermal induction electromotive force and good reproducibility of thermal cycle in short-term, nuclear irradiance and cold resistance characteristics, it can be partially replaced Thermocouple with S index number.
5. The characteristic of the K index is strong oxidation resistance, and it should be used continuously in a reducing and plastic atmosphere. The long-term application temperature is 1000°C, and the short-term application temperature is 1200°C. The most common application in all thermocouples.
6. The characteristic of E index number is that among common thermocouples, the thermally induced electromotive force is larger, that is, the sensitivity is the greatest. It is suitable for continuous application in a reducing and plastic atmosphere, and the application temperature is 0-800℃.
7. The characteristic of the index number of J is that it can be used in both reducing atmosphere (application temperature limit of 750°C) and oxidizing atmosphere (application temperature limit of 950°C), and resistance to H2 and CO vapor erosion, and is mostly used for oil refining Factories and chemical plants.
8. The characteristic of the T index number is the highest accuracy level among all low-cost metal thermocouples, and it is generally used to accurately measure the temperature below 300°C.
The above are the common index numbers and characteristics of thermocouples. Our company has been specialized in manufacturing thermocouples for more than 14 years. Our thermocouples have high precision, high and low temperature resistance, waterproof and corrosion resistance, and can be customized. If you have any questions about thermocouples, please feel free to consult!
