Pipeline defect detection system based on transmission-type terahertz spectrum

The utility model discloses a pipeline defect detection system based on a transmission-type terahertz spectrum. Comprising a fixed seat and a movable ring positioned on the fixed seat, the movable ring can rotate relative to the fixed seat; three groups of terahertz detection assemblies are distributed at equal intervals along the circumference of the moving ring; the polyethylene gas pipe is conveyed to a terahertz signal radiation area along with the conveying belt; the terahertz signal radiation area is an in-ring sampling area of the moving ring; the movable ring rotates in a reciprocating mode in the circumferential direction. Terahertz signals penetrate through the polyethylene gas pipe, information carrying the wall thickness and defects of the gas pipe is collected and imaged by the terahertz detector and then is transmitted to the computer for image data processing and analysis, a three-dimensional model of the polyethylene gas pipe is established, and potential defects are visually displayed and mar