气体超声流量计在长庆气田的应用

长庆油田第一采气厂79座集气站、3座净化厂、2座配气站的天然气计量系统中以孔板流量计为主，但由于受天然气气质、生产条件及外界条件的影响，在使用中经常出现标准孔板附着脏物、损伤、取压管路堵塞或泄漏等情况，导致维护工作量较大，也影响天然气的准确计量。为了提高天然气贸易计量的准确度，通过对各类流量计的性能优选，长庆气田2003年在“西气东输”天然气贸易计量系统中首次尝试应用Instromet、Daniel两种气体超声流量计，并开展孔板流量计的对比分析研究，大大提高了贸易计量管理水平及贸易计量准确度，取得了较好的应用效果及经验。为此，简述了气体超声流量计的工作原理、工作性能特点，气体超声波流量计量值溯源，探讨其应用中的不足，以期为气体超声流量计的现场应用提供参考。

APPLICATION OF GAS ULTRASONIC FLOWMETER IN CHANGQING GAS FIELD

The orifice plate flowmeter is the major kind of flowmeter used in the natural gas measurement system of the Primary Gas Production Plant of PetroChina Changqing Oilfield Company, which contains 79 gas gathering stations, 3 purification plants and 2 gas distribution stations. Nevertheless, the standard orifice is apt to be attached with dirty, and be easily damaged. The pressure sample tube is plugged or tends toward leak from time to time. All these problems in Changqing Gasfield are caused by the natural gas properties, production conditions and external conditions. It will lead to increasing amount of maintenance work and gas measurement inaccuracy. To boost the measurement accuracy of natural gas trade, Instromet and Daniel gas ultrasonic flowmeters were initially used by Changqing in the gas trade metering system of the "West-east Natural Gas Transmission Project". Comparison analyses and researches were performed on the orifice meter, which have substantially promoted the management level and accuracy for trade measurement and achieved favorable application effect and rich application experience in work place. The working principle and performance of gas ultrasonic flowmeter were briefly introduced. Its shortages during application were discussed. This will offer references for the on-site application of gas ultrasonic flowmefers.