1. Features of turbine flowmeter:
1) High accuracy, generally .25% r-.5% r for liquid, and .15% r for high-precision type; The medium is gas, generally 1% r-1.5% r, and the special type is .5% r-1% r. Among all flowmeters, it is the most accurate.
2) It has good repeatability, and the short-term repeatability can reach .5%-.2%. It is precisely because of its good repeatability, such as frequent calibration or online calibration, which can obtain extremely high accuracy, that it is the preferred flowmeter in trade settlement. ?
3) Output pulse frequency signal, which is suitable for total quantity measurement and computer connection, without zero drift and strong anti-interference ability. ?
4) Very high frequency signal (3-4kHz) can be obtained with strong signal resolution. ?
5) The range is wide, and the medium and large caliber can reach 4: 1-1: 1, and the small caliber is 6: 1 or 5: 1. ?
6) Compact and lightweight structure, convenient installation and maintenance, and large circulation capacity. ?
7) It is suitable for high-voltage measurement, and there is no need to open holes in the instrument body, so it is easy to make high-voltage instruments. ?
2. Working principle of the turbine flowmeter:
When the fluid flows along the axis direction of the pipeline and impacts the turbine blades, a force proportional to the product of the flow qv, the flow velocity V and the fluid density ρ acts on the blades to push the turbine to rotate. When the turbine rotates, the blades periodically cut the magnetic field lines generated by the electromagnet, changing the magnetic flux of the coil. According to the principle of electromagnetic induction, a pulsating potential signal will be induced in the coil, and the frequency of this pulsating signal is proportional to the flow rate of the measured fluid. Where qv is the total volume of fluid, and n is the total number of pulses generated by the flow sensor; ξ is the flow coefficient.
The important characteristic parameters of the turbine flowmeter sensor are different for different instruments, and change with the wear and tear of the instrument after long-term use; It means the number of pulses output by the flow sensor when the unit volume flow passes through the flow sensor. ?
the pulse signal output by the turbine flowmeter sensor is amplified by the preamplifier and sent to the display instrument, so that the flow can be measured.
3. The turbine flowmeter is suitable for:
liquid flow measurement in petroleum, chemical, light industry, food and other industries.