气体流量标准装置钟罩外径测量方法的研究

Measurement Methods for the Outer Diameter of Bell Type Prover of Gas Flowmeter Standard

钟罩式气体流量标准装置的钟罩外径测量是几何测量法中最重要的测量参数,其不确定度分析是否准确就成为必须解决的问题。以容积为100 L的钟罩为研究对象,应用π尺法、激光跟踪法和外径千分尺法3种不同的实验方法,分别对钟罩不同截面上的外径进行了测量。对测量结果进行了比较和分析,3种测量方法引入的不确定度都在允许的范围内,由此得到3种测量方法都是正确合理的结论。通过对数据的分析,就国产的钟罩而言,相对较好的测量方法是π尺法。

In the geometric method it is most important to measure outer the diameter of the bell type prover gas flow standard facility, so the main problem is to analyze the uncertainty. For the bell type prover that volume is 100 litre, three different methods including π ruler method, laser tracker method and micrometer method are applied to measure the outer diameter of the bell type prover. The outer diameter in different sections of the bell type prover is measured. The results were compared and analized, and the method are coherent. The research shows that all of these methods are proper. Through the analysis of the data, the π ruler method is more exact for the bell type prover produced in China.