(1) higher measurement accuracy
Compared with other velocity flow meters, the two-channel ultrasonic flow meter is less sensitive to the upstream obstacles such as elbow, pump or valve, and the reliability of the measurement results is high. Even if a channel stops working due to some reason, the flow meter can still continue to measure.The requirements of the typical inlet straight pipe section are at least 5D upstream and at least 2D downstream. Under the premise of meeting the above installation requirements, the measurement accuracy of the multi-channel ultrasonic flow meter can reach ± 0.5%.By contrast, the repeatability requirement of the electromagnetic flow meter under this precision is 1/3 of the accuracy, and the repeatability requirement of the ultrasonic flowmeter under this precision is 1/5 of the accuracy. Obviously, the requirements of the ultrasonic flow meter can be higher than that of the electromagnetic flow meter.
(2) lower requirements for straight pipe segment
Multi-channel ultrasonic flow meter due to use of velocity distribution and area distribution of double integral to calculate flow rate, so in the case of laminar flow and turbulent flow can accurately measure the flow rate, can achieve the measurement precision of the handover, at the same time it can realize the flow measurement range and measure the diameter is big, straight pipe for required small (3 d) after 10 d, at present the product on the market can do DN5000 is the biggest for pipe size, and the more easy to achieve high accuracy, the larger the diameter of multichannel ultrasonic flow meter diameter, in theory, can make any big.
(3) the measurement sensitivity is higher
Another feature of the multi-channel ultrasonic flow meter is that because the time measurement accuracy is very high, can reach picosecond, so it can achieve high measurement sensitivity, so as to ensure the accurate measurement at low flow rate (0. 05 m/s can reach 0.5%).The range ratio is relatively high, up to 400∶1.
(4) continuous flow with pressure construction and online maintenance can be realized
The insertion ultrasonic flow meter is different from the external clamping flow meter in that its sensor is in direct contact with water (medium).As with other flow meters, it is useful for factory pipe section products in the form of flange connections, and can also be installed in the field on the pipe in use.Most of the plug-in ultrasonic flow meters can be installed with continuous flow and pressure through the pressure installation tool. This technology can be applied not only in the old pipe network renovation project, but also in the new project, eliminating the expansion joint and connection flange, such as in the pipe network after water installation, can save investment and time.After years of use, due to water quality problems, scaling occurs on the wall of the pipe and the front end of the sensor, which may affect the signal sending and receiving of the sensor. At this time, the sensor can be removed from cleaning online through the pressure installation tool under the condition of continuous flow, so as to continue to ensure the measurement accuracy and stability of the flow meter.