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Description of the solution to reduce the accuracy of the flowmeter

There are a wide variety of flow meters on the market, and the range of use is also very common. The accuracy of the flowmeter has been determined at the time of shipment. However, in practical applications, we still have the result of lowering the accuracy, and the level of accuracy of each flowmeter is not the same. So how do we deal with the reduction in flowmeter accuracy? The following small series will give you a detailed introduction to the treatment of flowmeter accuracy reduction.

1, save installation
The accuracy of saving the installation of such instruments does not require fluid calibration. The factory test adopts the "dry standard" method, and the fundamental accuracy is probably calculated. The calculation is based on the “extra value” supplied by the demander. The density of the medium can be actively compensated and intelligently manifested. In this case, it is necessary to focus on whether the instrument device can meet the meter request, for example, the straight pipe segment. Length, if the request is not reached, the calculation of the additional deviation should refer to the instrument's clarification.

If the density of the medium is manually calculated, when the actual condition of the fluid medium is different from the planned condition, the flow performance value is multiplied by a modification factor for the individual gas, and T, Z, and P are resolved as the planned additional task conditions. The medium temperature, the tightening coefficient, and the medium pressure; t, z, and p are the media temperature, the tightening coefficient, and the medium pressure under realistic mission conditions.

Obviously, the temperature and pressure of the fluid in the actual task are randomly changed. The artificial compensation of the ultrasonic flowmeter can only make up for the uniform value, and the deviation is obvious. The better measure is to take the initiative to make up the intelligent instrument. For imaginary (or near-fantasy) gases, this remedy is highly commensurate, with an accuracy of ±1% for quality flow or volumetric flow.

It saves the installation to have a certain request for the straight pipe section, and the additional deviation caused by the unsatisfactory satisfaction can be delimited for the scale saving installation.

2, volumetric flowmeter
The additional deviation caused by the volumetric flowmeter under the premise of the actual task is due to the influence of the temperature and pressure of the fluid medium on the volume of the measuring chamber. Under the condition of the known cavity material, the volume change can be calculated. The meter readings are modified. The viscosity of the actual fluid may also have an effect on the meter reading, depending on the instrument's statement. The length of the straight pipe does not affect its accuracy individually, which is the strength of the bumps of this type of instrument. This type of meter represents the volumetric flow of the fluid under mission conditions. The weekdays required by the application are the volumetric flow or mass flow at scale, and the fluid density must be stopped. At the beginning of the new flowmeter, the intelligent performance instrument was applied and the density was actively compensated.

3, electromagnetic flowmeter
The reason of the electromagnetic flowmeter is based on Faraday's electromagnetic theorem. The inner diameter (fluent area) of the sensor has an influence on the measured value. When the pressure temperature of the fluid medium differs from the reference premise, the difference in the smooth area can be converted into a meter reading. Come out, or you must have a certain deviation. The meter has a lower request for the straight pipe section, and the pressure transmitter application should pay attention to it. There is no modification formula when the straight pipe section is lacking. The meter measures the volumetric flow under mission conditions. If volume flow or mass flow is required under scale conditions, the density compensation needs to be stopped.

4, turbo meter
This type of instrument is sensitive to the premise of the site, and the application is best satisfied with its request in order to adhere to the factory accuracy. When the temperature and pressure of the fluid medium are different from the reference premise, the volume change of the sensor housing can be calculated according to the material of the sensor and the temperature pressure plate, and the meter reading can be modified. When the viscosity of the fluid medium under the task condition is different from the viscosity of the calibration fluid, the modification should be stopped according to the viscosity modification curve supplied by the instrument manufacturer. The turbometer has a certain request for the length of the straight pipe of the high and low swim, and should be satisfied with the idea, especially when the user requests high precision. The meter represents the volume flow under the premise of the media task. If you want to know the scale volume flow or the mass flow, you need to stop the density compensation. Turbine meters have high measurement accuracy and are often used as scales to calibrate mission meters.

5, vortex flowmeter
The input static pressure level transmitter is sensitive to the premise of the site, and the application is best satisfied with its request in order to adhere to the factory accuracy. When the temperature, pressure and reference conditions of the fluid medium are different, the volume change of the sensor housing can be calculated according to the material of the sensor and the temperature and pressure plate, and the meter reading can be modified. The vortex flowmeter has a higher request for the length of the upper and lower straight pipe sections, and should be satisfied with the idea, especially when the user requests high precision. The meter represents the volume flow under the premise of the media task. If you want to know the scale volume flow or the mass flow, you need to stop the density compensation.

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