A dual element transducer sensor called a transceiver is used to both transmit and receive the ultrasonic signal
effectively with reflection as the sensing mode. The ultrasonic transceiver has the advantage of becoming a
transmitter at one time while can be as a receiver at the other time [12]. A transceiver Model UB300-18GM40-I-V1
shown in The transceiver’s frequency is 390 kHz with the diameter of 18 mm and the sensing range is from 30mm
up to 300 mm. Based on modelling, there are twenty-eight (28) transceiver sensors can be mounted around the pipe
with 14 mm distance between each other and 50 mm distance from the pipe surface. The fixed distance from the
transducer array to the pipe surface is decided as to optimize the number of sensor in ultrasonic sensing ring and the
image area for the sensor.