Abstract:A new method is presented that uses guided wave techniques for sludge and blockage detection in long-range pipelines. Existing techniques have the limitations that the sludge position needs to be known a priori and the area to be inspected needs to be accessible. A novel guided wave technique has been developed that allow the sludge or blockages to be detected remotely without the need to access the specific location where the pipe is blocked, nor to open the pipe. The technique measures the reflection of guided waves by sludge that can be used to accurately locate the blocked region. The effectiveness of the proposed technique is demonstrated and confirmed by experimental measurements.