阻塞计的校准方法研究

Study on Method to Calibrate Plugging Meter

阻塞计是监测钠中杂质浓度水平的最重要的在线测量仪表,为提高阻塞计的测量精度,提出了一种新的校准方法——冷阱控制法。实验通过控制冷阱冷点温度来控制钠中杂质的饱和温度,进而对阻塞计进行校准。实验中采用闭环控制模型准确控制了冷阱冷点的温度,冷阱冷点温度的波动范围为±0.5℃。共进行了28组实验,通过实验得到了阻塞温度的经验校准曲线。阻塞温度经校准后,校准值与理论值间偏差的范围为-0.654~0.653μg/g,平均绝对偏差为0.298μg/g,平均相对标准偏差为4.40%,校准曲线的残差概率图散点基本上呈直线趋势,残差服从正态分布,校准曲线的可信度较高。冷阱控制法较为简单,易于推广,该方法对阻塞计校准后,可提高其测量准确度。

Plugging meters are the most important online meters for measuring the concentration of impurities in sodium.In order to improve the accuracy of the plugging meters,a new calibration method,cold trap controlling method,was put forward.To determine impurity saturation temperature by cold trap in experiments,a closed-loop control model was used to control the temperature of the cold point,and the range of the temperature fluctuation of the cold point was±0.5℃in the experiment.28 groups of experiments were conducted,and an empirical calibration curve of plugging temperature was obtained.After the calibration,the range of deviation is-0.654-0.653μg/g,and the mean absolute deviation and mean relative standard deviation of experiments are 0.298μg/g and 4.40%,respectively.The residual probability scatters into a straight line trend basically,and the residual obeys the normal distribution,so the calibration curve has higher credibility.The accuracy of the plugging meters is improved by cold trap controlling method,and this method is simple and easy to popularize.