Ultrasonic flowmeter
Advantages of acoustic flowmeter:
1. Non-contact flow measurement
2. No flow obstruction measurement, no pressure loss.
3. Non-conductive liquid can be measured.
4. Wide pipe diameter range
5. Water, gas, oil, all kinds of media can be measured, its application field is very broad.
Disadvantages of ultrasonic flowmeter:
1. There are some limitations in measuring high temperature media.
2. High requirements for temperature of flow field.
3. The length of straight pipe section is required.
Electromagnetic flowmeter has many advantages in fluid flow and is widely used in various industries.
1There are no obstructing flow parts in the measuring pipe, no pressure loss, and the requirements of the straight pipe section are relatively low;
2 High measurement accuracy, strong stability, strong anti-vibration interference ability;
3 The measurement is not affected by changes in fluid density, viscosity, temperature, pressure and conductivity;
4 With a variety of electrodes and lining options, strong resistance to dielectric corrosion.
Of course, electromagnetic flowmeters have their own limitations:
1 The measuring medium must have a certain conductivity (generally greater than 5us/cm), and there are also certain requirements for measuring the initial flow velocity (generally greater than 0.5m/s).
2 The temperature of the measuring medium is limited by the lining material, and the measurement effect of high temperature medium is not good.
3 Can not measure gas, vapor and other media.
4 If the measuring electrode works for a long time, there may be scaling, which can be measured only after cleaning
5 For the high viscosity medium and solid-liquid two-phase medium, it is necessary to use high frequency excitation, low frequency low magnetic accuracy.
6 Due to the limitation of the sensor structure principle, the cost of large-caliber products is too high, resulting in the increase of product caliber and price.
7 Due to its principle limitations, the instrument sensor coil needs to be energized to generate a magnetic field, and the estimated power consumption is relatively high, which is not suitable for battery power supply.
Comparation
1. Magnetic flowmeter accuracy is higher than ultrasonic flowmeter’s.
2. Electromagnetic flowmeter’s price is affected by pipe diameters, but for clamp on ultrasonic flow meter, its price is unrelated with pipe diameter.
3. Magentic flow meter does no clamp on type, ultrsonic flow meter is optional for clamp on, can achieve non contact water flow meters.
4. Ultrasonic flow meter can work with non conductive liquids, like pure water. Electromagnetic flow meter just can measure conductive liquids.
5. Eletromagnetic flow meter can’t measure very high temperature liquids, but ultrasonic flow meter is ok to high temperature liquids.
Post time: Mar-31-2023