In the selection of thermocouple

Thermocouple selection according to the thermocouple temperature range, the required precision, using the atmosphere, the performance of the measured object, response time and the economic benefit and so on comprehensive consideration. Temperature at 1300 ~ 1800 ℃, the requirement and high accuracy, generally choose B type thermocouple; Required accuracy is not high, atmosphere and allow tungsten-rhenium thermocouples are available, and higher than 1800 ℃ generally choose tungsten-rhenium thermocouples; Temperature at 1000 ~ 1300 ℃ requires accuracy and higher available S type thermocouple and N type thermocouple; Under 1000 ℃ in general with K type thermocouple and N type thermocouple, below 400 ℃ general use E type thermocouple; Negative temperature under 250 ℃, and usually measured in T thermocouple, T thermocouple during low temperature stability and high precision. S type, type B, K type thermocouple is suitable for strong oxidation and weak reducing atmosphere, J type and T type thermocouple is suitable for weak oxidizing and reducing atmosphere, if use air tightness better protection tube, the atmosphere is not too strict.