The Measurement of the High Temperature Sodium Pipe in CEFR

The main causes of invalidation of heat transfer piping are stress, thermal displacement and vibration in fast reactor. Strain and displacement measurements are of particular importance in the commissioning and running periods, which is to ensure safety of nuclear reactor. The defect and abnormity of sodium piping can be discovered betimes by the strain and displacement measurements, and the hidden problems of piping can be avoided. Based on the investigation of measurement on piping of power plant, the strain and thermal displacement measurements are carried into execution on the main cooling systems of secondary circuit and the accident residual heat removal system of China Experimental Fast Reactor(CEFR) during the commissioning and running periods. According to the measure data, the accurateness of pipe stress analysis is validated, and the security of systems can be safeguarded. This paper describes the strain and displacement measurement on the high-temperature sodium piping, including the measure method for the double-layer piping, the test of detection capability of high temperature strain gauges, displacement measure device, the analysis and adjustment method of measure data, and so on.