In the production of fasteners, the most common injection molding defects are mold release agent oil stains, white spots, burrs and debris, of which oil stains are the most difficult to detect. White spots, burrs and debris have obvious features in the image, while products with oil stains are very similar in appearance to general good products, which are difficult to detect.Using the Segmentation and Classification technology of Solomon SolVision AI image platform, deep learning is performed for each type of surface defect. After the AI model is trained, it can immediately detect all types of defects including oil stains.