Abstract��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.
2017, Vol. 35 
