FAILURE ANALYSIS OF U-TUBE IN HIGH PRESSURE HEAT EXCHANGER

The analysis of cracking failure for U-tube in high pressure heat exchanger was made by means of Chemical composition analysis, mechanical properties tests, microstructure test, SEM analysis of fracture and energy spectrum analysis of corrosion product. Investigation shows that the chemical composition and mechanics properties of the tube meet the demand of relative standards and the cracking cause for the heat exchanger tube end was stress corrosion cracking in polythionic acid environment.