Flávio Gonçalve Cavalieri and Ana M. F. Fileti
GPS, Leakage, HDPE, Microphone
Detect leakages with precision is crucial for gas transport pipelines, avoiding huge financial and environmental losses.
This work aims to develop a spherical shaped device capable of displace inside gas pipes and determine the leakage location. The acquisition and storage of audio signals, picked up by a microphone, and also the geographic coordinates, provided by a GPS receiver module, allowed finding leak location.
A high density polyethylene HDPE pipe was made to perform the experimental data capture and analysis. The fluid used in the tests was the compressed air, supplied by a compressor. Two leaks were simulated by holes with different diameters, 2 and 4mm coupled to the pipe inlet valve.
Test results showed a great efficiency for leak detection using the acoustic-electronic device. Relevant phenomena were observed by applying the Fast Fourier Transform, such as: the increase of the amplitude components related to the leakage when increasing the air pressure, and the different frequency components caused by the two leak diameters.
The GPS module presented a positioning error when moving within the pipe. Tests conducted with a signal repeater ensured the GPS signal reception. Thus, the determination of leak position can be improved by the installation of repeaters at specific points along in the pipe.