The GB/T 5989-2008 standard specifies a differential heating test method for the load softening temperature of refractory materials. This method accurately determines the load softening temperature of refractory materials by simulating the deformation of refractory materials under constant pressure and increasing temperature. The standard specifies the test equipment, operation process and result judgment method. This allows enterprises to evaluate the performance of refractory materials under high temperature bearing conditions, providing a basis for the selection of high temperature equipment such as product mass control and industrial kilns, and helping to screen refractory materials that can serve stably in high temperature and heavy load environments.