Coaxial cable outer conductor welding seam centering system and installation method

The invention discloses a coaxial cable outer conductor welding seam centering system and an installation method. The coaxial cable outer conductor welding seam centering system is characterized by comprising a fixing base, a positioning piece support, a positioning piece, an upstream laser sensor support, a downstream laser sensor support and a laser sensor. The installation method comprises the following steps: pre-assembling the positioning sheet and the laser sensor; adjusting the posture of the positioning piece and the transverse position of the positioning piece support, so that the positioning piece is vertically arranged, aligned with the welding needle and located in the center of the production line, and the lower end is inserted into a longitudinally-wrapped outer conductor welding seam on the production line; after the positioning piece is fixed, the laser sensors on the two sides of the positioning piece are debugged respectively, so that the laser sensors are just located at the positions which