Abstract：The mathematical model of double extensometer coaxiality tester was analyzed. The method for the evaluation of measurement uncertainty was established. The coaxiality calibration test was carried out on a hightemperature creep endurance testing machine. According to technical specifications in JJF 1059.1-2012 Evaluation and Expression of Measurement Uncertainty, the sources of each component in uncertainty evaluation were analyzed and evaluated comprehensively. The practical operation method of coaxiality calibration was improved, which improved the accuracy of data.
2021, Vol. 39 
