Studying the effect of various gases on the output characteristics of thermocouple pressure transducers

Abstract

Experimental studies have shown a real possibility of using thermocouple (and in a broader sense) thermal converters to measure the pressure of various gases in a wide pressure range with a low error, subject to mandatory precalibration of the transducers for each of the gases or their mixture. In addition, a constant pattern of the dependence of the calibration characteristic of the thermocouple transducer for different gases is observed over the entire pressure range of 5 to 5 × 10−3 mmHg. Owing to this feature, a thermocouple transducer can be calibrated for different gases at one pressure point using a strain transducer, the readings of which do not depend on the type of gas; subsequently, certain coefficients can be used for any transducers of this type in a pressure range of 5 to 5 × 10−3 mmHg.