With the development of industrial production, people have increasingly high requirements for the accuracy and range of flow measurement. At the same time, with the development of instrument science and technology and the continuous improvement of material science and technology, flow measurement technology is advancing rapidly. In order to adapt to various applications, various types of flow meters have been introduced one after another. Currently, there are more than a hundred types of flow meters in use, classified from a principle perspective, among which the more common ones are electromagnetic flow meters, turbine flow meters, volumetric flow meters, differential pressure flow meters, and ultrasonic flow meters produced by MEZOLEN. For various types of flow meters based on different principles, there are subdivisions such as external clamp type, insertion type, and pipeline type, as shown in the following figure.
External clip type
Insertion type
Pipeline type
However, in actual production and life, there are various types of measured media. If the measured medium is a substance with relatively stable chemical properties, the measurement operation will be relatively smoother. However, if the characteristics of the measured medium itself are prone to crystallization or the medium is a mixture of multiple substances, such as solid-liquid mixtures of coal water slurry, the sensor probe may be attached by some viscous substances, crystals, etc. This problem is particularly targeted at flow meters with pipeline and insertion probes that directly contact the medium, thereby affecting the measurement work of the instrument itself. Today's introduction is aimed at this problem. The processing plan for ultrasonic flow meters developed and produced.
Ultrasonic probe with self-cleaning function
I believe many people have heard of, come into contact with, or even used products related to ultrasonic cleaning. The working principle of an ultrasonic cleaning machine is mainly through an ultrasonic transducer, which converts high-frequency electrical energy into mechanical vibration. The ultrasonic waves are radiated into the cleaning solution in the tank through the cleaning tank wall. The radiation of the ultrasonic waves makes the liquid flow and generates a large number of microbubbles. The microbubbles in the liquid in the tank can maintain vibration under the action of the sound waves, and these bubbles will cover the surface of the cleaning object, surrounding it layer by layer. Finally, after reaching a certain level of air pressure, the bubbles will burst, and the rupture of each bubble in the liquid will produce a powerful shock wave. This is what it means “Cavitation effect”. It will destroy the adsorption ability of dirt on the surface of the cleaning object, causing the dirt layer on the surface of the object to fatigue and be removed. In fact, ultrasonic cleaning machine achieves the effect of oil and dirt removal through cavitation effect, which is a physical cleaning method. So what kind of sparks can be generated by the collision between this principle and ultrasonic flowmeter?
The sensor probe of an ultrasonic flowmeter also converts high-frequency electrical energy into mechanical vibration, namely ultrasonic waves, through a transducer. When the sensor probe of the instrument is covered or stuck with some substance, the instrument can control the transducer to emit a certain frequency of ultrasonic waves. When it propagates into the liquid, the above-mentioned ultrasonic waves are generated inside the liquid “Cavitation effect”.
To achieve the purpose of cleaning the probe, the attached material on the surface of the probe is biologically stripped off by force. This process can be performed before or after each measurement of the instrument, or when the instrument determines that the signal is impure and automatically starts cleaning the probe. The specific timing of opening can be set according to the actual situation. This solution can solve or alleviate this problem that occurs during the measurement of such fluid media. This function is a unique feature of ultrasonic flow meters and will provide more possibilities for flow meters in various environments in the future.
