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为满足我国四川盆地东部大天池构造带天然气地面集输工程的工艺要求和天然气集输生产过程自动化而设置的大天池SCADA系统网络，实现了对井站、集气站、脱水装置的自动化控制，包括各种检测、控制调节和数据采集系统。文章说明了计算机计量系统的工作原理，现场天然气计量系统仪器、仪表的构成，所使用的流量计算方法；分析了影响计算机计量不准确度的诸多因素，且对整个系统总不确定度进行了计算，确定出影响误差的主要因素；另外，通过对同一计量点所做的对比实验（双波纹管差压计与自动化仪表计量相比较），证实计算机计量的准确性、抗干扰性都优于前者，同时还分析了影响现场仪表计量准确度的关键因素是仪表自身的准确度以及仪表所使用的环境条件。

APPLICATION OF GAS AUTOMATIC MEASURING SYSTEM 1)

Datianchi SCADA network is designed for the requirements and automation of gas gathering system for the structural belt of Datianchi gas field in Chongqing. It realizes the automatic control to well stations, gas gathering stations and dehydration devices, including different systems of monitoring, controlling, adjusting and data acquiring. The article describes the working principle of the computer system, the apparatus and instruments forming the gas measuring system, and the flow calculating method, analyzes the factors effecting the accuracy of computer measuring, calculates the total uncertainty of the whole system, and identifies the main factors effecting errors. With comparison test(comparing the bi bellows differential pressure gauge with the automatic instruments) at a same measuring point, it is proved the accuracy and anti jam of the computer measurement is better than that of the differential pressure gauge. Also, it is demonstrated the accuracy of instrument itself and the environment conditions of the instrument working are the key of affecting accuracy of field measurement.