In the field of industrial measurement, liquid electromagnetic flowmeter is an instrumentation device that occupies an important position. But a variety of factors will affect the accuracy of the liquid flow meter. Therefore, it is important to understand the basic issues of flowmeter measurement for better use of the equipment, to maximize the effectiveness of the equipment, and to promote the development of daily work.
• Mechanical Wear and Tear
General new liquid flowmeter after a period of time to break in, the gap between the gears will reach a suitable range, in this case, the flow leakage is relatively small. But the flowmeter gears will be depleted with long-term movement, generally speaking, after 2-3 years of use, the gap between the gears will become larger, the flow leakage will also become larger, thus affecting the measurement accuracy of the liquid flowmeter, so regular inspection and maintenance is necessary, and in special circumstances, but also for the corresponding replacement.
As the liquid temperature is a less controllable factor, when the temperature rises, the flowmeter in the gear gap will become larger, the flowmeter leakage will also become larger, but also need to consider is the temperature rise in the volume of the measurement space will also become larger, the medium by thermal expansion and other factors.
• Inappropriate Differential Pressure
When the differential pressure between the import and export of the liquid flowmeter is relatively small, the gear speed will be low, the amount of oil leakage will be relatively large; and when the flowmeter flow between the import and export of the pressure is large, the gear speed is fast, the amount of oil leakage will increase, the error is naturally larger. Therefore, only the import and export pressure control in the appropriate range, in order to reduce the error.
The above are a few factors that affect the measurement accuracy of the liquid flow meter, but may not be comprehensive enough. Understand the factors that cause the flowmeter error, for the measurement of the industrial sector to occupy the standardization of its production and improve the efficiency of the comprehensive utilization of resources is of great significance.
For improving the service life of the magnetic flowmeter, reduce the probability of failure, electromagnetic flow meter routine maintenance is very necessary. Daily maintenance should pay attention to several aspects:
First, regular cleaning of the electromagnetic flowmeter transmitter tube wall scaling layer, which helps to protect the insulating lining of good insulation properties;
Second, in production practice, the instrument end cap, daily inspection of junction port sealing, which helps to protect the dry environment inside the instrument as well as the instrument's high degree of sealing, to extend the service life;
Third, regular calibration of the zero point of the instrument, which helps to protect the effective grounding of the flowmeter.