• 《Rubber parts Appearance Inspection Code》: specifies the definition of terms such as rotten bubble, lack of material, flash, crack, spray, tear, bubble, burnt edge, impurities, prying, delamination, degumming, mold dirty, aging glue, less sulfur, uneven thickness, deformation, etc. For example, rotten bubble refers to the product surface is obviously prominent and honeycomb; Flash (burr) refers to the production of excess material in non-structural parts of the product; Bubble refers to the product surface is obviously prominent and spherical. At the same time, the corresponding inspection methods, inspection items and standards are clarified. If the vision requirements have normal vision, the illumination is normal fluorescent lamp, 40W fluorescent lamp is used when there is no daylight indoors, the eye distance from the product 30-40cm directly, the observation time is 10 seconds; The inspection standards for different defects are specified, such as the diameter of the rotten bubble shall not be greater than 0.5mm, the diameter of the bubble is less than 1mm, and the height or depth is less than 0.5mm.

• 《Appearance Inspection Standard for Injection and Rubber Part - Quality Management System》: applicable to all production and assembly according to specifications. The standard defines the test conditions, such as the test distance of 300±50mm, the test time of 10±5 seconds, the light intensity of 1000lux (from the overhead), the light type of D65-standard day light, the test needs to be carried out in the indoor temperature of 22±5 degrees. The inspection methods and acceptance criteria are given for classification of defects such as suction mark, distortion, flash edge, short shot, welding line, pouring mark, flow mark, burn mark, silver line, scratch, color difference, bulbous protrusion, color and tone, surface grain, impurity, refraction defect, and bad appearance caused by welding method. For example, the class 1 and class 2 appearance grades do not allow suction marks and distortion; class 1 and class 2 do not allow flash edges, class 3 is allowed when firmly attached to the product; Scratches are not allowed in class 1, minor scratches are allowed in class 2 (described in detail in the appearance quality file if necessary), class 3 is allowed, etc.

• 《O-shaped rubber sealing ring appearance quality inspection standard" GB 34452.2-1987》: specifies the appearance quality inspection standard of O-shaped rubber sealing ring, according to the shape, characteristics and size of O-ring defects, the classification of its surface defects and requirements. Quality grades include Class n (general), Class s (higher), Class nz or Class sz (Special) and are subject to agreement between supply and demand. The standard also specifies the meaning of the relevant letter symbols, such as d1 represents the O-ring inner diameter, d2 represents the O-ring section diameter. In terms of appearance quality, the size and tolerance of the finished O-ring should comply with the relevant regulations, no pores, cracks, bubbles are allowed, the surface should be smooth and clean, and the surface defects should not exceed the specified limit.

Different rubber products and application scenarios may need to refer to different standards, and the appropriate standard should be selected according to the actual situation for inspection. In addition, some specific industries or companies may also have their own internal standards, which may be more stringent or refined for specific product characteristics.