Abstract: The engineering field environment of nuclear power, shield structure, ship and ocean engineering and other industries is characterised by complex, unstructured and severe conditions, which has an urgent demand for the use of robots to replace manual welding operations. In order to solve the problem of welding operations in complex environments, this paper addresses the key technologies such as network communication, three-dimensional modelling, pose update, collision detection, data acquisition, and human-machine interaction. Based on digital twin technology, a teleoperation test platform for the welding robot has been established. This platform creates a real-time and reliable bi-directional data channel between the upper computer controlling the virtual robot and the lower computer controlling the physical robot, thereby achieving precise synchronous control of the poses of both the virtual and physical robots. At the same time, a robot teleoperation MIG welding test is carried out as the potential application scene of shield machine cutter plate field repair for Q345 steel plate material in 2G and 3G positions, and the welded seam with good appearance is obtained. The results show that the robotic digital twin and teleoperation technology has certain advantages in solving the high-quality welding under complex working conditions, and has a broad application prospect in the field of nuclear power, shield structure, ship and ocean engineering repair.