GB/T 1687.1 - 2016 is the first part of the series of standards for flexural testing of vulcanized rubber, which explains the basic principles for measuring temperature rise and fatigue performance in flexural testing. It shows that the flexural test simulates the stress deformation scenario of vulcanized rubber in actual use, and introduces the fatigue performance of the material by monitoring the temperature rise caused by repeated flexural during the test and evaluating the fatigue damage of the material after a specific number of cycles. This part of the standard lays the theoretical foundation for the implementation of subsequent specific test methods, and helps to accurately evaluate the performance of vulcanized rubber under dynamic stress.