控制图法在计量标准稳定性考核中的应用研究

Research on the Application of Control Chart Method in the Stability Assessment of Measurement Standard

以临界流文丘里喷嘴法气体流量标准装置的计量标准稳定性考核为例,探讨了控制图的建立与应用。首先利用统计控制限建立极差控制图(R图),在确认R图处于受控状态后,再建立平均值控制图(■图),并对控制图进行分析。不同于JJF 1033-2016《计量标准考核规范》中规定的■图控制限的计算方法,本文从计量标准稳定性考核要求的角度出发,确定■图的目标控制限。控制图能用来监控计量标准所提供的标准量值的变化情况,并基于稳定性考核的要求,直观、准确地对计量标准稳定性进行判断,预警可能发生的质量失控,保证计量标准的稳定性。

The establishment and application of control charts are discussed by taking the stability assessment of the metrological standard of the critical flow venturi nozzle method gas flow standard device as an example.Firstly,the range control chart (R chart) is established based on the statistical control limit.Then,the average control chart (■ chart) is established after the confirmation that the R chart is in a controlled state.And the analysis of control charts is further conducted.Starting from the angle of the requirement of the stability assessment,the target control limits of the ■ chart are determined.The calculation method of control limits of the ■ chart differs from the method stipulated in the JJF 1033-2016Rule for the Examination of Measurement Standards.This paper determines the target control limits of the mean value control chart from the perspective of the requirements of stability assessment of metrology standards.The control chart can be used to monitor the changes in the standard values provided by the measurement standard and,based on the requirements of the stability assessment,make intuitive and accurate judgments on the stability of the measurement standard,warn of possible quality loss,and ensure the stability of the measurement standard.