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Every device has its own specific usage guidelines, and vortex flowmeters are no exception. Today, I’ll tell you about two key points that should be taken into account when using vortex flowmeters. Determine the minimum flow rate and select an appropriate diameter. First, the upper and lower limits of flow rate as well as the normal flow rate specified for the process are analyzed; the flow rate in kg/m3 is converted into the flow velocity under operating conditions (in m/s). Within its normal measurement range, the Reynolds number Red lies between 2×104 and 7×106. Within this range, the accuracy of flow measurement can reach the level specified by the technical specifications; exceeding this range will result in significant measurement errors. Vortex flow meters can measure upper flow velocities; generally, this is 60 m/s for gases, 70 m/s for steam, and 7 m/s for liquids. The characteristic of vortex flowmeters is that they are sensitive to low flow rates but not to high ones; therefore, it is crucial to determine the lower flow limit for vortex flowmeters. Under normal circumstances, the gauge diameter selected should ensure that the gas flow velocity is not less than 7 m/s and the liquid flow velocity is not less than 0.7 m/s. If the flow rate does not meet this requirement, intermittent reduction or expansion should be appropriately employed to minimize pipe losses. When selecting the caliber, it is also necessary to avoid situations where the frequency generated by normal flow rates is around 50 Hz, as power-frequency interference entering the instrument is not easily detectable and can lead to measurement errors. Dynamic compensation must also be carried out. Since a vortex flow meter can only measure the volume of fluid under the current operating conditions in the pipeline, changes in parameters such as flow rate, pressure, and temperature cause changes in density, while the volume under operating conditions remains constant. As a result, the frequency generated by the vortex flow meter does not change; thus, the same frequency corresponds to different volumetric flows under various standard conditions. Therefore, when measuring gases and superheated steam, pressure and temperature compensation must be applied; when measuring saturated steam, pressure compensation is required, while for measuring liquids, temperature compensation is necessary. A vortex flow meter consists of a sensor and a display instrument. Generally, the accompanying display instruments come equipped with various compensation functions that users can adjust as needed. A vortex flow meter consists of a sensor, a counting and display unit, and a preamplifier. Its counting and display unit can count the signals output by the converter, thereby enabling functions such as recording, storing, calculating, and setting flow rates. Also known as its secondary instrument, it is composed of a microcontroller system. In addition, it can also be used to control the liquid crystal display to show information such as the measured instantaneous flow rate and total flow rate. However, some Yokogawa vortex flowmeters can communicate data with remote computers, featuring communication interfaces that are used for dynamic monitoring. Today, the editor will share with you two points that should be kept in mind when using vortex flowmeters. We hope this will be helpful for you in daily use. If you want to learn more interesting facts about instruments and meters, please follow us