I. Common occasions where ultrasonic flowmeters are mainly applicable
1. Environmental protection field: municipal sewage measurement, factory sewage discharge detection, etc. In this occasion, time difference method and Doppler method ultrasonic flowmeters are widely used.
2. Oilfield: cementing mud flow measurement, oilfield oily sewage flow measurement, water injection flow measurement, etc.
3. Water company: raw water measurement of rivers, lakes and reservoirs, tap water flow measurement. Multi-use time difference ultrasonic flowmeter.
4. Chemical metallurgy: industrial circulating water flow measurement, production process water consumption measurement
5. Mining: mine drainage flow measurement, etc.
6. Aluminum plant, steel plant, paper mill and other production process water consumption measurement
7. Food and pharmaceutical enterprises: chemical flow measurement, juice flow measurement, etc. production process water consumption measurement
8. Power plant, thermal power plant: production process water consumption measurement, cooling circulation water flow measurement, generator set coil cooling water flow measurement, etc.
II. Ultrasonic flowmeter maintenance
1. Ultrasonic flowmeter zero flow inspection
When the pipeline liquid is still and there is no strong magnetic field interference and strong vibration around, the meter head displays zero. At this time, the zero point is automatically set to eliminate zero drift. Small signal removal is required during operation. Usually, the flow rate is less than 5% of the full-scale flow rate, and it is automatically removed. At the same time, the zero point can also be adjusted through the menu.
2. Ultrasonic flowmeter panel keyboard operation
Before starting the instrument operation, you must first set the parameters effectively, such as the unit system, installation method, pipe diameter, pipe wall thickness, pipe material, pipe roughness, fluid type, two probe spacing, flow rate unit, minimum speed, maximum speed, etc. Only when all parameters are entered correctly can the instrument correctly display the actual flow value.
3. Regular calibration of ultrasonic flowmeter
In order to ensure the accuracy of the flowmeter, regular calibration is required. Usually, a higher-precision portable flowmeter is used for direct comparison. The measured data is used for calculation: error = (measured value-standard value)/standard value. The calculated relative error and correction coefficient are used to make the measurement error meet the error of ±2%, which can meet the measurement requirements.
4. Regular maintenance of ultrasonic flowmeter
For ultrasonic flowmeters with external transducers, there is no water pressure loss and potential leakage after installation. It is only necessary to regularly check whether the transducer is loose and whether the adhesive between the transducer and the pipeline is good; for plug-in ultrasonic flowmeters, it is necessary to regularly clean the impurities and scale deposited on the probe for leakage; if it is an integrated ultrasonic flowmeter, it is necessary to check whether the flange connection between the flowmeter and the pipeline is good, and consider the impact of on-site temperature and humidity on its electronic components, etc. Regular maintenance can ensure the long-term stable operation of the ultrasonic flowmeter.