Tomographic instrumentation system based on ultrasonic sensor for monitoring irregularities in pipe

Abstract

The formation of irregularities inside pipes is a common phenomenon that occurs in the chemical industry. The presence of irregularities on the surface of the internal pipe wall can lead to corrosion which eventually reduces its own integrity for operation. Many methods have been developed for the prevention and detection of this problem. An ultrasonic is one of the non-destructive methods used in the industrial sector. An ultrasonic instrumentation system has been developed in this project to detect the presence of internal irregularities in a pipe. The variations of ultrasonic signals were observed in the experiment when it passed through different conditions of the internal pipe surfaces. An ultrasonic Sensor EFC16T/R-2 with a frequency of 40 kHz was mounted outside the test pipe using a circle ring sensoring unit. The results showed that there were changes of output voltage when there were irregularities detected in the ultrasonic path. The output voltage was low in the range of 2.1333V to 3.1334V when there were no irregularities detected inside the steel pipe. The increase in output voltage from 5.4677V to 8.8667V indicated that the absorption of ultrasonic signals by irregularities had occurred. The collected data were processed using Matlab software to reconstruct the images inside the pipe. The reconstructed images showed the irregularities detected inside the pipe that resembled the actual conditions of the pipe. However, several images showed a slight inaccuracy of irregularities position in the test pipe compared to the actual condition of the pipe. This was due to the instability of ultrasonic signals, which could be easily affected by environmental factors and the presence of noise during the experiment. Nonetheless, it is believed that the developed ultrasonic tomography was able to monitor any irregularities present inside a pipe.