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I. The concession method The so-called concession method involves making concessions regarding a certain indicator; this approach is widely used in product quality management. For example, in chemical manufacturing, the products that come out at the end of the production process do not meet the standards for first-class products, but they do meet the standards for second-class products. As a result, they are sold as second-class products instead of being discarded, which is more economical. In field applications of electromagnetic flowmeters, if the length of the straight pipe section cannot be met under any circumstances, and if the flow measurement results are not intended for trade settlement but rather for general monitoring or process control, the compromise method can be attempted. II. Installation of a flow regulator A flow regulator can be used to reduce the length of the straight pipe section upstream. Compatibility tests show that it can be used downstream of any upstream fitting. Currently, only two types of flow regulators are listed in the main text of ISO5167: the 19-tube bundle flow straightener and the Zanker flow regulator plate. The standard specifies the applicable types of throttling and flow-blocking elements, as well as the exact installation locations for these flow regulators. III. Selecting the appropriate model Since different types of flowmeters have vastly varying requirements regarding the length of the straight pipe section, if the flowmeter chosen initially requires a long straight pipe section that cannot be satisfied under any circumstances, it is necessary to select a model with lower requirements for the length of the straight pipe section. IV. Evaluation of the influence factors When the length of the straight pipe section is insufficient, the uncertainty of the electromagnetic flowmeter increases, as the velocity distribution within the pipe becomes distorted, resulting in the actual flow coefficient of the instrument differing from the coefficient used during factory calibration. If a flow meter equipped with upstream and downstream pipe sections is assembled using the actual types of fittings and lengths of straight pipe sections present on site, and then placed on a flow standard device to determine the flow coefficient of that meter, it can be used in practice. The flow coefficient can then be utilized to calculate flow rates, thereby completely eliminating the impact of insufficient lengths of straight pipe sections on the measurement results. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012717174126829.jpg