Reasons for inaccurate accuracy of vortex flowmeters and solutions

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　　The vortex flow meter is a product that has been carefully designed by integrating advanced technologies from developed countries as well as years of experience in research and production. It achieves intelligence, standardization, series production, versatility, and the use of standardized manufacturing molds, thereby ensuring the aesthetic quality of the product. This product features advanced circuit design, low power consumption, a wide measurement range, simple structure, low resistance loss, durability, wide applicability, long service life, stable operation, and ease of installation and adjustment. 1. Effect of accumulation on the upstream surface of the vortex generator in vortex flow meters: If viscous particles are present in the fluid being measured, they may gradually accumulate on the upstream surface of the vortex generator, altering its geometric shape and size; as a result, the flow coefficient also changes. Therefore, it is necessary to clean this area regularly during use. 2. Effect of temperature on measurement The impact of temperature changes on the geometric dimensions of the measured object consists of two factors: one is caused by changes in the width of the vortex generator, and the other is caused by changes in the inner diameter of the pipe. To eliminate this effect, the K coefficient is generally adjusted. Currently, the flowmeters produced by some manufacturers perform fixed-temperature correction and real-time temperature correction in software to account for the impact of temperature. 3. Effects caused by a mismatch between the inner diameter of the piping used with the vortex flow meter and the inner diameter of the flow meter itself. 4. Issues related to selection: In practice, it is advisable to choose the smallest possible diameter in order to improve measurement accuracy. For example, if a vortex flow meter pipeline is designed to serve several devices, and some of these devices are not used at times, the actual flow rate in use decreases. This results in the originally selected diameter being too large, which in turn raises the lower limit of the flow rate that can be measured; as a result, accurate readings cannot be obtained at low flow rates. However, the meter can still function at higher flow rates, as redesigning it can be very difficult. Changes in process conditions are usually temporary. The indication accuracy can be improved by adjusting the parameters. 5. Installation-related issues: The main problem is that the length of the straight pipe section in front of the vortex flowmeter sensor is insufficient, which affects the measurement accuracy. For example, when there is clearly not enough straight pipe section in front of the sensor, and since the FIC203 is not intended for measurement but only for control purposes, its current accuracy can be considered as reduced. 6. Reasons for the direction of parameter tuning in vortex flowmeters 　Incorrect product parameters lead to inaccurate readings on the instrument. Incorrect parameters lead to errors in the calculation of the full-scale frequency of the secondary instrument. A small difference in the full-scale frequencies results in inaccurate readings over time, while an actual full-scale frequency that is much higher than the calculated value causes large fluctuations in the readings, making it impossible to obtain accurate values. Moreover, inconsistencies in the parameters provided in the documentation affect the final determination of these parameters. Such problems were resolved by re-calibrating the instruments and comparing the results.