The electromagnetic flow meter is an efficient and accurate flow meter that is widely used in the water supply industry and has become one of the most commonly used flow meter types in urban water supply and sewage treatment. However, during the measurement process of the electromagnetic flow meter, sometimes the flow velocity of the measurement pipe is too low, resulting in the measurement component being unable to detect the generation of the flow signal. In order to solve this problem, diameter reduction can be adopted.

Diameter reduction refers to increasing the flow rate by changing the cross-sectional area of ​​the pipe, so as to meet the minimum requirements of the electromagnetic flow meter. Specifically, the diameter of one of the two sections of pipeline before and after the electromagnetic flow meter is installed can be reduced. Before the diameter reduction process, detailed measurements and calculations are required to ensure that the flow rate after the change in the pipeline cross-sectional area meets the requirements of the electromagnetic flow meter and will not affect the normal operation of the pipeline. According to the actual situation, select the appropriate diameter reduction method and length. Usually, tapering, expansion, etc. can be used for diameter reduction.

In addition to diameter reduction, the measurement accuracy of the electromagnetic flow meter can also be improved by increasing the flow rate of the pipe. Specific methods include increasing the diameter of the pipe, shortening the length of the measurement pipe, increasing the flow rate of the water pump, etc. When selecting a method, comprehensive considerations need to be made based on the specific situation to achieve the best measurement results.

In addition, in order to ensure the accuracy and stability of the electromagnetic flow meter, a series of inspection and maintenance work are required during installation and use. Before installation, the pipelines need to be cleaned and inspected to remove impurities and foreign matter to ensure smooth flow inside the pipelines. During use, regular calibration and maintenance are required to find and solve problems in time to ensure the accuracy and stability of the electromagnetic flow meter.

As a type of flow meter widely used in the water supply industry, electromagnetic flow meters have become the most used type of flow meters in urban water supply and sewage treatment due to their excellent measurement performance. In practical applications, electromagnetic flow meter need to meet a certain flow rate range to accurately measure flow. However, due to the different water quality and water properties in the water supply system, sometimes the flow rate in the pipeline is too low, and in this case it is necessary to reduce the diameter of the pipeline.

Diameter reduction treatment refers to adding a section of reducer to the pipeline to increase the flow rate and meet the measurement requirements of the electromagnetic flow meter. The specific operation method is to first select appropriate pipe materials, pipe fittings and valves according to the system requirements, select the pipe diameter according to the parameters after the system is combined, and select an electromagnetic flow meter with a sensor diameter smaller than the measurement pipe diameter. Because the diameter of the pipeline being measured is inconsistent with the surface diameter of the electromagnetic flow meter, reducers are added before and after the local pipeline where the electromagnetic flow meter is installed to increase the flow rate and meet the flow rate range requirements of the flow meter.

It should be noted that it is very important to choose the appropriate reducer length and diameter ratio, which requires actual measurement and calculation according to the specific situation. In addition, in order to ensure the effect of the diameter reduction treatment, the pipelines need to be cleaned and maintained to prevent debris and dirt in the pipelines from affecting the flow rate and measurement accuracy.

The application and diameter reduction of electromagnetic flow meter have been widely practiced and experienced in the water supply industry. Through scientific design and precise operation, the problem of low flow velocity in the pipeline can be effectively solved and the accuracy and stability of the electromagnetic flow meter can be ensured, thus providing strong support for the production and development of the water supply industry.

Electromagnetic flow meter are widely used in the field of water supply measurement because their measurement principle is based on Faraday's law of electromagnetic induction and is suitable for measuring volume flow in conductive liquids and slurries. However, in practical applications, the different water properties of users may cause the water flow rate in the pipe to be low, which cannot meet the flow rate requirements of the electromagnetic flow meter. Therefore, diameter reduction processing is required. The diameter reduction process is to select an electromagnetic flow meter with a sensor diameter smaller than the measurement pipe diameter after selecting the diameter of pipes, pipe fittings and valves, and add reducers before and after the sensor to increase the flow rate of the electromagnetic flow meter. However, when performing reducing work, it must be noted that the reducer must meet the taper requirements. According to product requirements, the gradually expanding or contracting cone angle of the pipe sections before and after the sensor should be less than15°, otherwise it is necessary to customize an extended tapered or tapered tube to meet the requirements.

For example, a large chemical plant selected based on its original design water consumptionDN300Electromagnetic flow meter water meter set, but due to the requirements of the straight pipe section of the electromagnetic flow meter and the water meter room of the unit is too long and narrow, consider using an electromagnetic flow meter with a smaller pipe diameter of one or even two grades, and perform diameter reduction processing. However, based on the standard atlas reducer size calculation,DN300x200 and DN300x100The central cone angle of the reducer is greater than15°, does not meet product design requirements. Therefore, it is necessary to specially customize non-standard gradually expanding and reducing tubes, and lengthen the length of the reducing part to reduce the central cone angle to the taper requirement.15°Within.

In practical applications, in order to meet the flow rate requirements of the electromagnetic flow meter, designers can make flexible changes based on the user's water consumption and the actual situation on site to save investment in the water meter set and enable the flow meter to operate in better working conditions. In addition, the upstream side of the electromagnetic flow meter should have no less than5A straight pipe section that is twice the diameter of the pipe, and the downstream side should be no less than3A straight pipe section that is twice the inner diameter of the pipe. If there is a gate valve or regulating valve that is not fully open upstream, the length of the straight pipe section upstream of the flow meter should be increased to10Times the inner diameter of the pipe.