Pipe deformation inspection is an application of in-line inspection technologies, and its principle is: install mechanical probe, electronic recorder and battery on the pig, so as to convert it into a deformation inspector; when running in the pipeline, the probe installed on the inspector can detect and record the pits on the pipe, ovality, circumferential weld, pipe thickness variation, position and other signals; after taking out the inspector, read the technical data on the recorder, and analyze with data analysis software, so as to obtain the deformation amount and specific position of the pipe.