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When selecting a gas turbine flowmeter, the following factors should be taken into consideration: 1. Flow range: The choice of the flow range for a turbine flowmeter has a significant impact on its accuracy and service life. Moreover, each size of flowmeter has a specific measurement range, and the selection of the flowmeter’s diameter is also determined by the required flow range. The principle for selecting the flow range is that the minimum flow rate during use should not be lower than the minimum flow rate that the instrument can measure, and the maximum flow rate during use should not be higher than the maximum flow rate that the instrument can measure. For applications with intermittent operation where the actual daily operating time of the instrument is no more than 8 hours, 1.3 times the maximum flow rate under actual use is taken as the upper limit for the flow range; for applications with continuous operation where the actual daily operating time of the instrument is at least 8 hours, 1.4 times the maximum flow rate under actual use is taken as the upper limit for the flow range. The lower flow limit for the instrument is appropriately set at 0.8 times the minimum flow rate in actual use. 2. Accuracy level: Generally, turbine flowmeters are chosen due to their high accuracy. However, the higher the accuracy of a flowmeter, the more sensitive it is to changes in operating conditions on site. Therefore, careful consideration should be given to the choice of accuracy level, taking economic factors into account. For trade settlement instruments used in large-diameter gas pipelines, it is cost-effective to invest more in high-precision instruments; whereas for applications with lower flow rates, instruments of moderate precision are sufficient. 3. Pressure loss: Try to choose turbine flowmeters with low pressure loss. Because the pressure loss of the fluid as it passes through the gas turbine flow meter is the smaller, the less energy is consumed by the fluid as it moves from the inlet pipe to the outlet pipe; in other words, the total power required is reduced. This allows for **energy savings, lower transportation costs, and improved efficiency. 4. Gas density: For gas turbine flowmeters, the fluid property that has the greatest impact is the gas density; it significantly affects the meter’s coefficient, especially in low-flow regions. If the gas density changes frequently, corrective actions must be taken regarding the flow coefficient of the flow meter. 5. Bearings: The bearings in turbine flowmeters are generally made of three materials – tungsten carbide, polytetrafluoroethylene, and carbon graphite. The bearings of natural gas metering instruments should be made of tungsten carbide. 6. Structural type: (1) For the internal structure, a back-thrust turbine flowmeter is recommended. Because the reverse thrust structure allows the impeller to remain in a floating state within a certain flow range, with no contact points in the axial direction and thus no end-face friction or wear, which helps to extend the service life of the bearings. (2) The selection is based on the piping connection method; flow meters can be installed horizontally or vertically. For horizontal installation, the piping connection methods include flange connection, threaded connection, and clamp connection. Flange connections are used for medium-diameter pipes; threaded connections are used for small-diameter and high-pressure pipes; clamp connections are only suitable for low-pressure pipes of small to medium diameter; threaded connections are the only option for vertical installations. (3) Select the model according to environmental conditions, taking into account the effects of temperature and humidity. For natural gas measurement, an intrinsically safe explosion-proof turbine flowmeter should be selected. Flow metering is one of the components of measurement science and technology, and it is closely related to the national economy, national defense construction, and scientific research. Doing this work well plays an important role in ensuring product quality, improving production efficiency, and promoting the development of science and technology. Especially in today’s era of energy crises and an increasing level of automation in industrial production, the significance and role of flow meters in the national economy have become even more evident.