用双计时法检定换向器不确定度的探讨

Investigation on Uncertainty of Changeover by Using Double-timing Method

为研究液体流量标准装置动态启停法检定机械式累积流量仪表时的换向系统对称特性,提出了用双计时法检定换向器系统的不确定度。试验结果证明了气动电磁阀工作非对称性是换向器系统不确定度的主要来源。研究结果表明,采用双计时法检测换向器所得不确定度比传统检测方法检测结果要大,比较符合装置实际使用情况。

In order to research the symmetry feature of changeover system in calibrating mechanical flow totalizing instruments with standard facilities using dynamic start-stop, the double-timing method is proposed to test the uncertainty of changeover system. The tests show that the asymmetry of the pneumatic electromagnetic valve is the primary factor forming uncertainty of changeover system. The result of research indicates the asymmetry measured by double-timing method is bigger than that of testing by conventional method, but it is much applicable in real conditions of the facilities.