Investigation of a manual plugging meter for monitoring impurities in sodium

The principle, structure and experimental results of the manual plugging meter are described for measuring impurity concentration in sodium. In order to reduce measurement error, the authors investigate some factors which affect accurate measurement of plugging temperature and have found the way to reduce the error. The experimental results show that the differences between the concentrations for the high plugging temperature and the low plugging temperature at different levels of impurity concentrations are almost same. The difference for hydrogen is 0.0763 ppm, 1.03 ppm for oxygen