基于双计时原理的水表和换向器检定方法研究

Research on the Measurement Method of Watermeter and Changeover Based on Double-timer Method

为提高水流量标准试验装置检测大口径机械式水表示值误差的检定精度,提出一种基于动态启停双计时原理的检定方法。依据两台计时器分别记录的被检水表通流时间和工作量器进水时间,可以方便地修正示值误差并对换向系统工作特性进行监测。研究结果证实,换向气动电磁阀不对称工作特性是换向系统不确定度的主要来源,双计时法能明显提高机械类流量仪表的示值误差检定不确定度。

In order to improve the accuracy of the measurement standard system for big-inch mechanical watermeters, a new method based on the principles of flying start and stop and double-timer methods is proposed. According to separately recording the time of watermeter tested and flow into the tank by the double timer, it is easy to provide correction and monitor the performance characteristics of the changeover system. The result of the research proves that the unsymmetry of air-operated electromagnetic valve is the primary source of uncertainty . The uncertainty of the indicating errors of mechanical flowmeters could be improved effectively by the double-timer method.