Pipeline direction detection technology. The combination of inertial navigation system and inspection technology is another great progress of internal inspection technology. It can not only determine the direction of pipeline, but also facilitate the scientific management of pipeline. At the same time, the geological hazards may be produced in complex geographical environment or region of the pipeline, this technology can also be the detection of pipe bending strain, is an important complement of pipeline safety evaluation compared with the developed countries, the domestic start later, in the early 1980 s began to carry out the study of pipeline inspection technology, the real application in pipeline inspection technology and achievements, It should be traced back to China Oil Pipeline Inspection Technology Co., LTD. (hereinafter referred to as China Oil Pipeline Inspection) in 1994.