What are the graduation numbers of high temperature thermocouples? What are their characteristics?
The indexing numbers of thermocouples are mainly 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.
1.The characteristic of S index number is strong anti-oxidation. 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 induction electromotive force is about 15% larger, and the other characteristics 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 a reducing or neutral atmosphere, and can also be used in a short time under the vacuum pump standard.
4. The characteristics of the N index number are strong high temperature oxidation resistance at 1300℃, long-term reliability of thermal induction electromotive force and good reproducibility of thermal cycle in the short term, nuclear irradiance and cold resistance, and can be partially replaced Thermocouple with S index number.
5. The characteristic of K index is strong anti-oxidation, it is suitable for continuous application in reducing and plastic atmosphere, the long-term application temperature is 1000℃, and the short-term application temperature is 1200℃. The most common application in all thermocouples.
