The insulation coating of bare wires is an important measure to ensure the safety and reliability of power transmission. The design of the coating mechanism for bare wire insulation coating robots is the key to intelligent coating. This article proposes a new type of wheel group clamping coating mechanism suitable for multiple types of bare wires. It has a conventional sag adaptive design, which can stably walk on the wire, achieve uniform coating, and meet the requirements of different coating thicknesses by adjusting the movement speed. Through mechanical analysis, software simulation, and experimental verification, it is shown that the vibration of the front and rear wheels during operation is not uniform, forming the pitching motion of the entire mechanism. The speed fluctuation remains at around 70mm/s, with a fluctuation rate of about 23%. After 0.2 seconds of coating startup, the operating speed of the nozzle and the output torque of the driving wheel tend to stabilize, proving that the mechanism has characteristics such as stable performance and smooth walking, It provides a new solution for the insulation coating of bare wires and has important application value.