There are many kinds of ultrasonic flowmeters. According to different classification methods, it can be divided into different types of ultrasonic flowmeters.
(1) Working measurement principle
There are many kinds of ultrasound flowmeter for closed pipelines according to the measurement principle, and the most used are the two categories of transit time and Doppler ultrasonic principle. The transit-time ultrasonic flowmeter uses the principle that the transit time between the sound wave propagating in the flow and the counter-current propagation in the fluid is proportional to the flow rate of the fluid to measure the flow rate of the fluid, which is widely used in the measurement of raw water in rivers, rivers and reservoirs, the detection of petrochemical products process flow, and the measurement of water consumption in the production process. According to the practical application needs, transit time ultrasonic flowmeter is divided into portable time difference ultrasonic flowmeter, fixed transit time ultrasonic flowmeter, transit time gas ultrasonic flowmeter.
(2) Classified according to the measured medium
Gas flow meter and liquid flow meter
(3) The propagation time method is classified according to the number of channels
According to the number of channels classification commonly used mono, double channel, four-channel and eight-channel .
The four-channel and above multi-channel configuration has a great effect on improving the measurement accuracy.
(4) Classified by transducer installation method
It can be divided into portable, handheld type and fixed installation type.
(5) Classification according to the transducers type
Ultrasonic flowmeter is divided into three kinds: clamp on type, insert type and flange & thread type.
Clamp-on ultrasonic flowmeter is the earliest production, the user is most familiar with and the application of ultrasonic flowmeter, the installation of the transducer without pipeline break, that is, it fully reflects the ultrasonic flowmeter installation is simple, easy to use characteristics.
Some pipelines due to thin material, poor sound conduction, or serious corrosion, lining and pipeline space gap and other reasons, resulting in serious attenuation of ultrasonic signal, with the external ultrasonic flowmeter can not be measured normally, so the generation of pipe segment ultrasonic flowmeter. The tube segment ultrasonic flowmeter integrates the transducer and the measuring tube, solving a difficulty in the measurement of the external flowmeter, and the measurement accuracy is higher than that of other ultrasonic flowmeters, but at the same time, it also sacrifices the advantage of the external attached ultrasonic flowmeter not to break the flow installation, requiring the installation of the transducer through the cut pipe.
The insertion ultrasonic flowmeter is in the middle of the above two. The flow can not be interrupted on the installation, the use of special tools to punch holes in the pipeline with water, and insert the transducer into the pipeline to complete the installation. Because the transducer is in the pipeline, the transmission and reception of its signal only passes through the measured medium, but not through the tube wall and lining, so its measurement is not limited by the tube quality and tube lining material.
Post time: Jun-09-2023