GB/T 13477.7-2002 Focus on the determination of low temperature flexibility of building sealing materials. The standard specifies the test method in detail, specifies the required equipment, such as low temperature boxes, bending tools, etc. Describe the preparation steps of the specimen, set the low temperature environmental conditions, and the bending operation process. By bending the sealing material specimen at low temperature, observe whether there is crazing, fracture, etc., to evaluate its low temperature flexibility. This provides a key performance test basis for the application of building sealing materials in cold regions or low temperature environments, and helps to ensure the effectiveness and durability of building sealing projects under low temperature conditions.