The ultrasonic flowmeter is designed based on the geometrical principle that the velocity of the ultrasonic wave propagating in the flowing medium is equal to the average flow velocity of the measured medium and the velocity of the acoustic wave itself. It is also measured by the flow rate to reflect the flow rate. Although the ultrasonic flowmeter appeared only in the 1970s, it is very popular because it can be made into a non-contact type and can be connected to the ultrasonic water level gauge for opening flow measurement without disturbing or resisting the fluid. There are promising flow meters.
Ultrasonic Doppler flowmeters fabricated using the Doppler effect have received widespread attention in recent years and are considered to be ideal gauges for non-contact measurement of two-phase flow.
Fluid oscillating flowmeter
The fluid oscillating flowmeter is designed based on the principle that the fluid will oscillate when flowing under specific flow conditions, and the frequency of the oscillation is proportional to the flow velocity. When the flow cross section is constant, the flow rate is proportional to the flow volume of the pilot volume. Therefore, the flow rate can be measured by measuring the oscillation frequency. This flowmeter was developed and developed in the 1970s. Because it combines the advantages of non-rotating components and pulsed digital output, it has a promising future. At present, typical products include vortex flowmeters and spiral vortex flowmeters.
Second, the compressed air vortex flowmeter installation steps
1. The special flanges to be equipped are welded to the upstream and downstream straight pipe sections respectively, so that the inner diameters of the special flange and the straight pipe section are strictly vertical and concentric.
2. Install the sensor clip on the upper and lower straight pipe sections welded with special flanges and fasten them with bolts. The upstream and downstream straight sections should be kept concentric with the sensor.
3. It should be noted that the flow direction of the sensor should be consistent with the flow direction of the fluid in the pipeline.
Third, special attention should be paid when installing compressed air vortex flowmeter
1. When welding special flanges and straight pipe sections, the sensor should be removed and the sensor welding flange must not be carried.
2. Before the sensor is installed, the sealing ring must be placed in the groove of the flange.
3. The pressure point and temperature measurement point should be at the 3DN~5DN and 6N~8DN downstream of the sensor.
4. When the high temperature pipeline is insulated, do not wrap the sensor to avoid damage.
5. The cable connecting the vortex flowmeter should be as far away as possible from the interference of strong electromagnetic fields. It is absolutely not allowed to lay with high voltage cables. The shielded cable should be as short as possible, the maximum length should not exceed 500 meters, and should not be coiled to reduce the distributed inductance.
Battery powered electromagnetic flowmeter features
1. Micro power consumption design, five 3.6V lithium batteries, continuous operation for 5~10 years, and easy to replace the battery.
2. The display adopts LCD large-screen liquid crystal display, which can display multiple flow parameters such as instantaneous flow rate, flow rate (pipe pressure), cumulative total amount of forward and reverse, and alarm prompt.
3. There are no movable and resistance parts in the measuring tube, no entanglement or clogging phenomenon, almost no pressure loss, and long-term reliable and continuous work.
4. Wide measurement range: The flow rate measurement range can reach 0.05m/s~10m/s.
5. High measurement accuracy: ±0.5% ~ ±1.0%.
6. Measurement stability: The measurement accuracy is not affected by changes in physical parameters such as temperature, pressure, viscosity and density of the measured medium.
7, with pulse output and GSM wireless data remote transmission.
8, with data storage function, up to 1000 groups of traffic data can be saved, and the data storage time can be arbitrarily set and data query.