，要求将标准内容详细描述一下
Light Rail External Shape, Delivery Weight and Surface Quality (GB / T 11264-1989)
Light rail is transported by railway and used in railway operations. It is an important part of the railway infrastructure. Light rail external shape, delivery weight and surface quality are important indicators to ensure the operation safety of railway transportation and the quality of light rail.
GB / T 11264-1989 stipulates that the surface defects of light rail should meet the requirements, and the external shape and delivery weight should also meet the design requirements. The requirements of light rail external features, delivery weight and surface quality are as follows:
1. External shape. According to GB / T 11264-1989, the light rail is divided into 5 external shape categories: 8kg, 12kg, 18kg, 22kg and 30kg. They must meet the relevant requirements of external shape of the corresponding type. It is required that the difference between the front and back head sizes, the rail waist size and the upper rail size of the same cross section light rail should not be greater than 1.5mm; the longitudinal profiles of the head and waist of the same rail section should not be greater than 5.0mm; The rail edges of the head, waist and upper rail should have no burrs or a small round of burrs not exceeding 0.2mm, and the upper edges should be rounded and clear.
2. Delivery weight. According to GB / T 11264-1989, the delivery weight of light rail should meet the design requirements for each type of light rail, and the delivery weight variance of each grade of light rail should not exceed 3%.
3. Surface quality. According to GB / T 11264-1989, the surface quality of the light rail must meet the requirements. It is required that the light rail surface of the 8kg, 12kg, 18kg, 22kg and 30kg levels should have no subsurface cracks, X-ray or other visible defects, and no delamination, corrosion or steam stains; The surface of the head and waist should have no obvious black, white, line and unfeeling defects, and other obvious defects; the butt surface of the same temperature should have no triangulation, wedging or other serious unevenness; the surface should have no oil, adhesion or intense local blackening.
GB/T 11264-1989 established the standards for light rail external shape, delivery weight and surface quality. These standards are important to ensure the safe operation and good quality of light rail. Rail operators should strictly abide by the relevant provisions of this standard, properly use and maintain the light rail, and correctly handle related problems to ensure the safe running of the light rail.
