国家石油天然气大流量计量站检定工艺的优化

Optimization of verification process in national large oil/gas flowrate metering stations

国家石油天然气大流量计量站采用直排检定工艺进行流量计检定,在乌鲁木齐分站工程可行性研究过程中,发现检定工况存在高压、大压差、直排管道工艺复杂、温度不稳定等技术难题。基于此,从调整分站压力、流量和计量系统入手,提出了一套天然气计量直排检定工艺优化方案,同时需要注意以下几点:流量调节过程中,分、调流系统和压力调节系统之间相互不影响;在设计过程中,应以"等压切换、分流调节"作为操作原则;分流、调流操作应能较快调节至各流量检定点,并使流量在短时间内稳定;不改变原有直排管道工艺、调压工艺和计量方式;利用直排管道原有计量调压设备,减少投资。该工艺计量站的推广应用,可为国内计量检定站设计提供借鉴。

In national large oil/gas flowrate metering stations, the collinear verification is normally used for meters. The feasibility study of the Urumqi sub-station project has revealed some challenges for the verification, such as high pressure, large pressure differential, complex collinear pipeline technology, and instable temperature. In this regard, this paper presents an optimized collinear verification process in gas metering by adjusting the pressure, flowrate and metering system in the substation. However, the following aspects should be considered：（1） flowrate division/adjustment system and pressure regulating system should not interact during the flowrate adjustment;（2） design should be made on the principles of ＂switching at constant pressure and adjusting by flowrate division＂;（3） flowrate division and adjustment should enable the rapid operation to all flowrate verification points and stabilize the flowrate in a short time;（4） original collinear pipeline process, pressure regulating process and metering approach should not be changed; and（5） current metering and pressure regulating equipment of collinear pipeline should be remained to reduce the investment. The promotion and application of this optimized process in the sub-station will provide a reference to the design of other metering and verification stations in China.