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Vortex flow meters are designed and manufactured based on the Karman vortex street principle. Flow rate is measured by applying the principle of fluid oscillation. As the fluid passes through a vortex flow transmitter in a pipe, two rows of vortices are generated alternately above and below the vortex generator, which is shaped like a triangular prism; these vortices are proportional to the flow velocity. The frequency at which these vortices are generated is related to the average velocity of the fluid flowing past the vortex generator as well as the characteristics of that vortex generator. A turbine flowmeter is a device that uses a multi-bladed rotor (turbine) to detect the average flow velocity of the fluid, thereby determining the flow rate or total volume. Turbine flowmeters are widely used for measuring various substances such as oil, organic liquids, inorganic liquids, liquefied gas, natural gas, gas, and other low-temperature fluids. It features a simple structure, few components required for manufacturing, low weight, easy maintenance, high flow capacity (a large volume of fluid can pass through at the same diameter), and the ability to operate under high parameters (high temperature, high pressure, and low temperature). In market use, vortex flowmeters are primarily employed for measuring the flow rate of fluids in industrial pipelines, including various media such as gases, liquids, and vapors. It is characterized by low pressure loss, a wide measurement range, and high accuracy; when measuring volumetric flow rate under operating conditions, it is hardly affected by parameters such as fluid density, pressure, temperature, and viscosity. There are no moving mechanical parts, thus it offers high reliability and requires minimal maintenance. In current market applications, users should be aware that flow meters must be used within the technical parameters defined by the working pressure and temperature range of the medium. Do not deliberately choose instruments with high pressure ratings and extremely high temperatures; instead, select instruments based on the actual operating pressure and temperature, as the latter are more expensive. The lower flow limit of a vortex flow meter depends on the density and kinematic viscosity of the fluid under operating conditions, while its upper flow limit is generally not affected by the pressure and temperature of the fluid. Therefore, to determine the flow range, it is sufficient to identify the actual lower flow limit that is available for use. After calculating the minimum flow rate, consult the flow range table to determine the corresponding diameter. When selecting a flow meter, it is advisable to avoid operating it at the lower limit of its range; therefore, the diameter of the flow meter should be as small as possible to achieve higher flow velocities and a wider flow range.