Contact High Temperature Strain Automatic Calibration and Precision Compensation Technology

Abstract

In order to solve the problem of contact high temperature strain precision measure-ment, this paper established an automatic calibration device for high temperature strain gauges. The temperature of the high temperature furnace was automatically con-trolled by the temperature control device. The electric cylinder was driven by the servo motor to apply the load to the calibration beam. The output signal of the high temperature strain gauge, the thermocouple signal and the displacement signal of the grat-ing ruler were collected at the same time. The deformation measurement results obtained after temperature correction were used to calculate the theoretical mechanical strain, which were fed back to control the loading action to complete the automatic calibration process. Based on the above calibration device, the high temperature strain measurement accuracy correction software was developed to calibrate the high temperature strain gauge with multi-parameters, and the curves of sensitivity coefficient, thermal output, zero drift and creep characteristics with temperature were obtained, and a strain measurement accuracy compensation model was established. The high temperature strain measurement experiment was carried out to verify that the modified model can meet the requirements in each temperature range.