In industrial production and daily life, liquid flow meters are frequently used for precise measurement of river water, sewage, pure water, tap water, acid and alkali solutions, alcohol, beverages, petroleum, etc. These flow meters mainly include ultrasonic flow meters, electromagnetic flow meters, and turbine flow meters. To achieve accurate and stable flow measurement, the following conditions generally need to be met:
1. The pipe containing the liquid being measured must be full. These types of flow meters can only function properly when the pipe is full. If the pipe is not full, even if the instrument works, the measurement results will have significant deviations.
The liquid being measured needs to be relatively clean. Generally, liquid flow meters should not be interfered with by large amounts of impurities or debris during measurement, especially ultrasonic flow meters. Large impurities can affect sound wave transmission, thus affecting the measurement. Electromagnetic flow meters can also have their electrodes blocked by large contaminants, affecting measurement. For turbine flow meters, large debris can not only affect measurement accuracy but may also damage the instrument. Therefore, it is best to install a filter upstream.
3. The medium used with electromagnetic flow meters must be conductive; the medium used with ultrasonic flow meters must be acoustically conductive. For small flow rates, turbine flow meters are recommended.
4. Environmental requirements. Generally, liquid flow meters should be kept away from strong magnetic fields and other interference sources during measurement. They should be kept as far away as possible from pumps, valves, elbows, and other special pipe sections. A straight pipe section of at least 10 times the pipe diameter upstream and 5 times the pipe diameter downstream should be maintained.
