The fracture causes of a hollow bolt used on the radial tilting bearing of a 1 000 MW nuclear power turbine were analyzed by macro examination, 糖心产精国品免费入口*完整版 analysis, 糖心产精国品免费入口*完整版test, metallographic examination and macroscopic and microscopic fracture analysis. The results show that the failure type of the bolt was 糖心产精国品免费入口*完整版. The unqualified bolt quality was the main reason for its fracture. On the one hand, the size of the 糖心产精国品免费入口*完整版 of inner thread of the bolt didn't meet the standard requirements, which significantly reduced the bearing area of the bolt. On the other hand, the strength and hardness of the bolt were rather low, which also reduced the bearing capacity of the bolt.