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As a new type of flow measurement instrument, the intelligent helical vortex flowmeter offers highly effective performance in chemical production. It can automatically correct the temperature, pressure, and compressibility factor of the gas during measurement, through the collaboration between the sensor unit and the intelligent computing unit, in order to accurately determine the total flow rate of the gas. However, due to the inherent fixed error factors of the machine itself, as well as the influence of the environment and operating conditions on the measuring instruments in use, measurement errors occur. What this article aims to explore is how to minimize the errors caused by the influence of the factors mentioned above, and to identify the identifiable factors that lead to such errors; this will play a very important role in improving the accuracy of gas measurement, especially in areas such as natural gas metering. 1. Performance of the rotational vortex flowmeter itself (1) Straight pipe section The length of the straight pipe section must be standard and adequate; this affects the performance of the measuring instrument, as the measurement results are influenced by the flow conditions of the fluid. Therefore, there should be a sufficiently long and properly configured straight pipe section before and after the flowmeter to ensure stable flow of the fluid. Generally, the straight pipe section before the meter should be no less than 5D, and the straight pipe section after the meter should be no less than 1D. (2) Flow range Due to differences in specifications, the flow range of vortex flow meters also varies. Additionally, such meters are unable to detect flows below the lower limit, and it is difficult to maintain their accuracy in such conditions ； At the same time, when the gas flow rate is too high and exceeds the standard, it can lead to pressure loss, loss of pulses, and inaccuracies in measurement. In such situations, it becomes extremely difficult to maintain accuracy. (3) Pressure Accurate pressure measurement plays a decisive role in the precise determination of gas quantities. The pressure at the measurement point is inversely proportional to the relative error; the higher the pressure, the smaller the relative error. Therefore, when selecting a flow meter, it is necessary to take into account the maximum pressure under operating conditions and choose an appropriate sensor range accordingly. 2. Measurement errors caused by changing working conditions (1) Mechanical vibration The accuracy of the vortex flow meter decreases due to the intense mechanical vibrations in the pipeline. (2) Gas impurities The sensor of the vortex flowmeter has high requirements regarding gas quality; gases containing impurities or contaminants can clog the flowmeter during flow, affecting the sensor’s ability to measure the frequency of vortex rotation. Therefore, the gas separation or filtration efficiency should be good. Based on comparisons of gas flow rates during the same period, when there is more dust accumulation inside the rotameter, the measured gas flow rate is reduced by approximately 3% compared to when there is no dust accumulation. Due to its long construction period, the Mouda pipeline of the civil natural gas transmission network has iron sulfide particles formed inside its pipes, which reduces the accuracy of sensor readings ； At the same time, the various components and connection points of the flow meter have very high requirements regarding the quality of the gas. The presence of liquids in natural gas can corrode the sensors of the flow meter as well as its connection points. Gaskets are typically used at these connection points, and liquid droplets there can form an electrolyte solution that corrodes the gaskets. Once the gaskets of a flow meter are corroded, even minor leaks that occur can affect its ability to provide accurate measurements. (3) Electromagnetic interference: When developing this vortex flowmeter, the manufacturer took into full account the need for the flowmeter to be able to continue operating in the event of a power outage. Therefore, the manufacturer’s preset parameters as well as the calibration settings are stored in the electrically erasable programmable read-only memory (EEPROM) located in the flowmeter’s controller. However, when encountering other strong interferences (lightning, overhead high-voltage lines), some of these parameters change. The instrument’s display shows some irregular measurement results, causing the instrument to become dysfunctional. 3. Other reasons: Proper maintenance of the swirl vortex flowmeter has been carried out ； Drift of relevant parameters ； Bypass internal leakage ； Violation of operating procedures ； Failure to calibrate on schedule ； Equipment damage, etc., are also causes of measurement errors. During the production process, various phenomena can occur; for example, unstable medium flow, an undersized measurement range, and frequent fluctuations in the process can all lead to measurement errors. Sudden changes in flow rate and pressure cause the medium to become a pulsating flow; when the differential pressure increases or decreases, resulting in significant pulsations, measurement errors can be substantial. Ideas for reducing errors: 1. Choose the appropriate range properly. To ensure the accuracy of flow measurement, it is necessary to take into account various interfering factors during the design, installation, and use of flow meters, and to implement corresponding preventive measures. When installing a flow meter, follow the manufacturer’s instructions carefully to ensure proper operation, and avoid having the instrument operate constantly at its upper or lower limits. Under normal circumstances, the flow range of a flow meter is between 20% and 90% of the maximum flow rate under the operating conditions of that flow meter. Smart progressive cavity flow meter: during normal measurement, the flow rate is less than or equal to 1.5 times the maximum operating flow rate ； When the flow rate is 1.5 times or greater than the maximum operating flow rate, the flow meter exhibits a significant negative deviation, and may even lose pulses. 2. Proper installation of the flow meter When installing a swirl vortex flow meter, due consideration should be given to the surrounding environment and the cleanliness of the medium. The installation location of the flow meter should avoid vibrations and high temperatures as much as possible; it should be kept away from elements that can disrupt the flow pattern, such as compressors, separators, pressure regulators, tees, elbows, etc. The inner walls of the straight sections before and after the meter must be smooth and straight. The fluid being measured should be a clean, single-phase fluid, with a straight section of at least 5D in front of the meter and at least 1D behind it. When the fluid contains droplets and trace particulate impurities, it is necessary to prevent these crude oil particulates from accumulating around the vortex generator, thereby avoiding measurement errors ； In winter, the flow meter housing should be insulated to prevent water accumulation; therefore, it must be installed in strict accordance with the instructions and the actual conditions. During the installation of the flow meter, it is essential to determine the flow direction of the medium, as it must not be installed in the reverse direction. 3. Proper selection of pressure rating The pressure measurement accuracy of rotameter-type vortex flowmeters must be calculated in terms of relative error, whereas the accuracy of pressure sensors is generally determined based on application error. An intelligent rotameter must accurately detect the pressure of the medium in order to ensure accurate flow measurement. Currently, the common pressure ratings for sensors used are 0.6, 1.0, 1.6, 2.5, 4.0, and 6.0 MPa. In intelligent flowmeters, segmented correction is applied to pressure detection; when the medium pressure is not less than 1/3 of the design pressure, the relative error in pressure detection can be kept at no more than ±0.4% ； However, when the pressure is below 1/3 of the design pressure, the relative error may not be guaranteed to be less than ±0.4%. Therefore, the sensor range should be determined based on the maximum pressure of the actual medium at the site; otherwise, if a pressure sensor rated for higher pressures is used to measure low pressures (not exceeding 1/3 of the design pressure), the required accuracy of the flow meter cannot be ensured. 4. Strengthen routine maintenance: (1) Plot curves to analyze parameters under different gas supply pressure and temperature conditions, in order to determine the optimal gas supply pressure parameters ； (2) Plot curves for the instantaneous flow rate on a daily basis for tracking and comparison, in order to identify the patterns of changes in peak gas consumption ； (3) Plot curves to track and compare the daily gas supply volume, in order to identify the patterns of changes in peak gas consumption ； (4) Analyze the upper and lower limits for the daily gas supply flow measurement, in order to select a flow meter with relatively reasonable measurement limits ； Select the appropriate type of vortex flowmeter to reduce measurement errors at the source ； Conduct an analysis of gas supply conditions, identify patterns in gas usage, and improve the metering management system ； (5) Regularly assess the gas usage of downstream users to understand the relationship between the number of users and their gas consumption, and adjust the metering devices accordingly. Explore the factors that affect the operation of flow meters, reduce or eliminate those factors that impact accurate measurement, and improve measurement accuracy. (6) To reduce measurement errors, the swirl vortex flowmeter should be sent to a qualified calibration facility for calibration across its entire range before official installation ； Check the battery condition from time to time, and inspect the gauge factors and seal status ； During use, regularly inspect or clean the vortex flow meter and other components ； Regularly check the status of the instrument process flow, and address any issues found promptly ； Calibrate the instruments regularly (usually once per year). For more information, please visit the company’s official website at http://www.yb1518.com/. Please keep this link when reproducing the content! http://www.yb1518.com/UploadFiles/20101022185438865.jpg