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How to select and calibrate liquid mass flow meters - focus on microfluidic control technology

Liquid mass flow meters are widely used in many fields due to their own advantages. The selection work is also a very important task. How to choose the right type? Let's look at it together.
Before selecting the liquid mass flowmeter, collect the measured fluid composition, maximum flow rate, minimum flow rate, maximum working pressure, maximum temperature, and minimum temperature data. The selection is largely governed by fluid properties, so that for the selected flow meter or measurement method, not only the nature of the fluid to be measured is adapted, but also a change in the fluid properties due to a change in the fluid properties. The amount of influence should also be able to adapt.
The various parameters of the fluid under the conditions of use and the technical specifications of the selected instrument are usually found in the evaluation manual. For those components of the fluid that are not well understood, the relevant user must actively consult with the manufacturer to determine whether the selected instrument can be used normally. In addition, the liquid mass flow meter selection should be adjusted according to the site conditions, so that the appropriate flow meter can be selected.
The liquid mass flow meter is fully functional, intuitive, easy to operate and use, and can reduce the inconvenience caused by other electromagnetic flowmeter English menus. The measurement accuracy is further ensured and the grounding ring is not needed at any time, which reduces the trouble of the instrument volume and installation and maintenance. The measurement accuracy is not affected by changes in fluid density, viscosity, temperature, pressure and conductivity. The sensor induced voltage signal and the average flow rate are linear. Relationship, so the measurement accuracy is high.
When using liquid mass flowmeters, due to the influence of error factors caused by working conditions and environmental changes, after the analysis of uncertainty and the verification of field experimental data, in order to meet the requirements of on-site use, the flowmeter needs to be performed. Calibration, then how to calibrate the liquid mass flow meter? We summarize the following:
Working condition check: According to the requirements of the liquid mass flowmeter instruction manual, first check to determine if the flowmeter is working properly. According to the flowmeter verification certificate or the factory checklist, check whether the input of the key parameters affecting the measurement accuracy in the converter is correct. Pipes with stop flow conditions, check the flow rate of the flowmeter.
For remote verification, the flowmeter must be removed and sent to a secondary or primary flow standard for verification. These new calibration factors are then entered into the existing data acquisition system. Although remote verification may provide higher accuracy, the method may not be accurate and true from a system perspective, and the method is expensive and laborious to operate.
Performance measurement: Refer to the flowmeter, which is generally the same as the model being used, and can be connected to the components under test. This method provides a more accurate view of system performance because it operates under real conditions. However, this technique also has disadvantages, which typically reduce flow measurement accuracy because it may require the use of multiple reference flow meters for fluids in this range. For liquid mass flow meters, since most flow sensors show their maximum error at the lower end of the measurement range, more than one reference flow meter is required. Furthermore, improper compensation of the actual test conditions with reference to the initial calibration of the flow meter can also increase unknown and uncontrolled measurement errors.

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