螺栓断裂失效分析

Bolt fracture failure analysis

对断裂的高压天然气压缩机平衡管法兰螺栓的金相组织、化学成分、力学性能及断口的宏、微观特征等进行了综合分析,并结合压缩机设计文件资料、运行状态等,找出其断裂的原因。结果表明,在交变载荷的长期作用下,紧固螺母与设备结合处螺栓的螺纹根部存在应力集中现象,致使该部位成为裂纹源,最终螺栓发生疲劳断裂。

The microstructure,chemical composition,mechanical properties,macro and micro fracture morphology of the balance pipe flange bolt,which was ruptured,of the high pressure natural gas compressor were analyzed comprehensively. Crack reasons of the broken bolt were found according to the design documents and the running state of the compressor. Results showed that the stress concentration occurred in the connecting position between the nut and the equipment under the long-term alternating load. Thus,that zone became the crack source,which ultimately led to the bolt fatigue rupture occured.