Abstract: This paper introduces an X-ray non-destructive testing (NDT) robot for tension clamp sleeves used in high-voltage transmission lines, capable of adapting to different conductor spacing. Through mechanical design and drive circuit development, the robot can be deployed onto the line by suspending a traction rope with a drone and pulling it using a winch. The core innovation lies in an adjustable walking mechanism that dynamically adapts to varying conductor spacing, combined with an obstacle-crossing motor drive system that enables stable traversal of obstacles such as Stockbridge dampers to reach the target inspection location. During detection, a multi-degree-of-freedom imaging system precisely positions the tension clamp sleeve. Meanwhile, the robot can complete in-service non-destructive testing without power outage, enabling the timely detection of internal defects in compression fittings and effectively preventing accidents such as conductor breakage or dropping caused by poor crimping quality.