Clamp-on ultrasonic level meter, as the name implies, is because the ultrasonic level meter does not need to open a hole, and the probe is placed outside the pipeline, so it does not need to directly contact the medium. Because many level meters need to directly contact the medium, many working conditions are complex, and some working conditions that require strict sanitary conditions, such as the milk industry, are not suitable for these level meters that directly contact the medium, Therefore, the clamp-on ultrasonic level meter is widely used in these industries with special working conditions.
Of course, the clamp-on ultrasonic level meter is not only applicable to these complex working conditions, but it can also be applied to various working conditions, except the gas industry, so some people will ask, what is the clamp-on ultrasonic level meter, and what are its applicable occasions? Then I will tell you what an clamp-on ultrasonic level meter is.
The clamp-on ultrasonic level meter is a kind of high-frequency pulse sound wave sent by the ultrasonic transducer (probe). When it encounters the surface of the measured level (material), it is reflected back and the reflected echo is received by the transducer and converted into an electrical signal. The propagation time of the sound wave is proportional to the distance from the sound wave to the object's surface. The relationship between the sound wave transmission distance S and the sound speed C and the sound transmission time T can be expressed by the formula: S=C × T/2.
The probe part emits an ultrasonic wave, which is then reflected by the liquid surface, and the probe part receives it again. The distance from the probe to the liquid (object) surface is proportional to the time of the ultrasonic wave:
Hb=CT2, i.e
Distance [m]=time × Sound speed/2 [m]
Temperature compensation formula of sound velocity: ambient sound velocity=331.5+0.6 × temperature
The clamp-on ultrasonic level meter is composed of three parts: an ultrasonic transducer, a processing unit, and an output unit.
1. No mechanical movable part, high reliability, simple and convenient installation, non-contact measurement, and relatively low accuracy not affected by liquid viscosity, density, etc.
2. Polypropylene waterproof shell is adopted. The shell is small and quite solid, with excellent chemical resistance. For inorganic compounds, no matter acid, alkali, or salt solution, except for strong oxidizing materials, it has almost no destructive effect on them. It is insoluble in almost all solvents at room temperature and can be used on general media such as alkanes, hydrocarbons, alcohols, phenols, aldehydes, ketones, etc.
3. Lightweight, no scaling, and no medium pollution.
4. Non-toxic. The utility model can be used for the installation of equipment in the pharmaceutical and food industries, and maintenance is extremely convenient.
Through the introduction of the clamp-on ultrasonic liquid level meter, we must have a clear understanding of the clamp-on ultrasonic liquid level meter. Since there are so many performance characteristics of the ultrasonic liquid level meter, can it be applied to all working conditions? That's not the case. Although the ultrasonic liquid level meter does not directly contact the medium, it also has its limitations.
1. There should be no obstacles below the sound wave. The ultrasonic level meter is a sound wave reflection principle. Obstacles will affect the ultrasonic emission, resulting in signal loss;
2. The ultrasonic level meter test is easy to have a blind area;
3. Pressure vessels should not be measured. The pressure mainly affects the probe, and there is also a certain relationship between pressure and temperature, T=KP (K is a constant), so the change of pressure affects the change of temperature, and then affects the change of sound velocity;
4. In the actual measurement, the temperature will also cause measurement error, and the change in temperature will lead to a change in sound speed. Advanced measuring systems, including temperature sensors and system functions, can automatically compensate for the influence of temperature. In practical application, because the temperature of the probe's surrounding environment is different from that of the measured medium, the measurement system will select the temperature sensor combined with the probe and the clamp-on temperature sensor separated from the probe for temperature compensation;
5. Dust is one of the most influential factors in ultrasonic level meter measurement. Dust environment has little impact on sound speed, but it has obvious attenuation on a sound wave, so it is better not to use it in this situation;
6. The ultrasonic level meter cannot be used in the situation with water mist, media that is easy to produce a large amount of foam, and volatile media, which is easy to absorb sound waves or interfere with sound wave emission, resulting in signal loss and precision decline.
Therefore, you must be very familiar with your own working conditions when purchasing. Otherwise, the clamp-on ultrasonic level meter you bought won't work. It will not only waste money but also affect industrial production, which will not pay off. Hangzhou Meacon is a professional manufacturer of clamp-on ultrasonic level meters. If you have any questions about clamp-on ultrasonic level meters, you can consult Hangzhou Meacon's online customer service or call Hangzhou Meacon's hotline.