Factors affecting the accuracy of Rotameter during use

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　　Rotary vane flow meters are commonly used in the settlement of natural gas transactions; therefore, measurement accuracy has always been a goal that we strive to improve. In addition to the effects of the manufacturing process itself, there are many other factors that can influence the metering accuracy during actual use, mainly including the following aspects: 1) Measuring high-pressure gases using devices designed for low-pressure applications. It involves installing a metering chamber on the high-pressure pipeline, then using a pressure regulator to adjust the pressure. Users consume gas through the low-pressure pipeline. When the gas consumption by the users on the low-pressure pipeline is low, according to the gas law of states, at roughly constant temperatures, the low flow rate in the low-pressure pipeline results in an even lower flow rate in the high-pressure pipeline; in some cases, this flow rate is not even sufficient to reach the threshold required for the flow meter to start functioning. The flow meter does not count. So it will cause significant measurement errors. 　　2) An unreasonable pipeline design may cause significant measurement errors. Figure 2 shows a simplified diagram of the actual pipeline installation; there are two parallel pipelines, and when the main pipeline network is in use, the manual valve of the branch pipeline network is closed. The flow meter functions properly. When the branch pipeline also uses gas, the manual valve opens; as a portion of the gas in the main pipeline is diverted to the branch pipeline, the pressure in the main pipeline decreases. This results in the pressure before meter No. 1 being lower than the pressure behind it, causing the meter to operate in reverse direction and to accumulate flow volume, which leads to double counting of the flow. To avoid this situation, a check valve must be installed in front of flow meter No. 1. 　　3) Proper installation methods help improve the measurement accuracy of the flow meter and extend its service life. When installing the flow meter on the pipeline, it is necessary to ensure that the threaded holes on the flow meter’s body are aligned with those on the pipeline flange, as well as to maintain the parallelism of the flanges. This prevents the flow meter from being subjected to external forces, which could cause the meter’s body to deform and lead to jamming. To start the flow meter, the front valve should be opened first, followed by the slow opening of the rear valve, so that the flow meter can start under pressure. This prevents the gas from causing deformation of the flow meter’s rotor due to the air hammer effect, which could lead to the meter getting stuck. 　　The above is an analysis of the factors that affect the use of Roots flow meters in field applications. If you have any additional comments or suggestions, feel free to leave them in the comments section; we look forward to making progress together with you.