Abstract: Fine detection of underground pipelines refers to the use of special instruments and methods for key pipelines, difficult pipelines and special pipelines in key areas of engineering construction on the basis of conventional underground pipeline detection, and provides more accurate and more detailed results for design and construction through high-quality, high-density or high-precision detection. The fine detection of non-excavation pipelines is the most important one, and has always been a difficult problem in the industry, as conventional material detection equipment for such pipeline detection seems powerless. Through the application example in this essay, the accuracy and reliability of Ritchie SR-20 combined with micro tracer probe and inertial gyroscope positioning technology in the fine detection of non-excavation pipelines are verified, and the fine detection of non-excavation pipelines is able to be achieved depending on the site conditions and pipeline depths.

Key words: non-excavation, underground pipeline, fine detection, micro tracer probe, inertial gyroscope