GB/T 11026.9 - 2016 is part 9 of the heat resistance standard for electrical insulating materials, providing guidelines for calculating heat resistance using simplified procedures. It describes the simplified methods that can be used in evaluating the heat resistance of insulating materials, covering the scope of application, the determination of relevant parameters and the calculation process, and guides how to obtain key indicators of heat resistance through specific simplified steps. With the help of this standard, the heat resistance characteristics of insulating materials can be calculated efficiently and conveniently, providing a quick reference for the design and material selection of electrical equipment, and helping to improve work efficiency while ensuring the safe operation of electrical equipment.