The probe should be installed on the side of the pipe in order to avoid cavities produced by gases accumulated at the top of the pipe that affect the transmission and reception of ultrasonic signals. If the probe cannot be installed on the side, it is important to ensure that the pipe is filled with fluid at all times. Any gap between the probe and the tube walls will result in substantial attenuation of signal intensity, seriously affecting signal strength and quality. Therefore, a coupling agent must be applied between the head of the probe and the tube wall during installation to ensure that no air bubbles remain between the probe and the tube wall.
