The invention discloses a method for automatic coloring penetration detection in a pre-detection stage of a
power station pipeline. A detection instrument is adopted for detection; the detection instrument comprises a mechanical arm, a movable
chassis and a height adjusting arm, the height adjusting arm is arranged on the movable
chassis, the mechanical arm is installed at the end of the height adjusting arm, and the detection instrument is provided with cleaning rag and
terminal equipment. The detection agent comprises a
cleaning agent, a penetrating agent and a developing agent; the detection method sequentially comprises the following steps: performing pre-cleaning, performing
drying, applying a penetrant, removing excess penetrant, performing
drying and applying a developer. The environmental conditions are as follows: in the whole detection process, the temperature of the penetration detection agent, the surface temperature of the workpiece and the
operating temperature are withinthe temperature range of 10-50 DEG C. According to the invention, the surface of a detected part can be accurately identified, and manual actual addition of a
cleaning agent, a penetrating agent anda developing agent is replaced, so that the harm of the penetrating agent and the developing agent to a
human body is avoided, the
field detection efficiency is improved, the detection period is shortened, and the labor cost is reduced.