On-line system for replacing insulator of power transmission line

The invention relates to the technical field of power equipment, and discloses an on-line system for replacing an insulator of a power transmission line, which comprises a front positioning hoop and a rear positioning hoop which are arranged at different insulators of the same suspension insulator string, a pull-back piece used for adjusting the distance between the front positioning hoop and the rear positioning hoop is arranged between the front positioning hoop and the rear positioning hoop. A front claw capable of sliding in the radial direction is arranged in the front positioning hoop through a claw adjusting mechanism, and the front claw is used for being matched with an iron cap so that the front positioning hoop can be fixed to a suspension insulator string. A rear claw capable of sliding in the radial direction is arranged in the rear positioning hoop through a claw adjusting mechanism, and the rear claw is used for being matched with an iron cap so that the rear positioning hoop can be fixed to the