关键词: 比值法, 内锥, 三级差压, 双节流装置, 文丘里, 虚高模型

Abstract: Wet gas always occurs in oil and natural gas industry, so the accurate measurement of wet gas is of great significant. At present, make use of single phase meter after gas-liquid separator is the common method in wet gas measurement, but this method has a higher cost. So in order to meter the wet gas without separation online, a novel measurement device composed of a long throat Venturi tube and a V-cone is proposed and a new metering method based on triple differential pressures is put forward. In this method, the ratios of the differential pressures are vital parameters used to establish the measurement correlations. The comparisons of these correlations in laboratory and fields are also presented. In laboratory test, the measurement accuracy of the gas and liquid are 2.13% and 6.68% respectively. Field performance test results show that the relative error of gas flow rates is 7.87%, and the full scale error of liquid flow rates is 15.96% before the correction, and after field correction the average relative error of the gas metering is less than ±3%, the full-scale errors of the liquid metering is less than ±10%.

Key words: Cone, Dual-throttle device, Over-reading correlation, Ratio method, Triple differential pressures, Venture