The ultrasonic flowmeter is used for control measurements or to quickly detect flow rate in a pipe, making it a portable and easy-to-install measuring system.

The ultrasonic flowmeter works according to the transit time difference method. The flowmeter's measuring principle is very simple. For a diagonal measurement in a pipe, less time is required for a measurement in the direction of flow than in the opposite direction. As the flow rate increases, more time is required for a measurement in the opposite direction, and less time is required for a measurement in the opposite direction. The difference between flow times in the direction of flow and counterflow directly depends on the flow velocity. The flowmeter uses this effect to determine flow velocity and flow rate. Electroacoustic transducers receive and transmit brief ultrasonic pulses through the medium flowing in the pipe.

The transducers are positioned vertically and offset on both sides of the pipe to be measured. The non-invasive sensors are placed on the pipe and secured, for example, with a cable tie. The display quickly indicates the flow velocity. The ultrasonic flowmeter can be used on metal, plastic, and rubber pipes.