LUO Honghui, LONG Huiguo, WANG Peng. Analysis of Large Area Cracks of Boiler Headers Pipe Base for 660 MW Ultra Supercritical Units[J]. 2020, 40(5): 35-38.
LUO Honghui, LONG Huiguo, WANG Peng. Analysis of Large Area Cracks of Boiler Headers Pipe Base for 660 MW Ultra Supercritical Units[J]. 2020, 40(5): 35-38.DOI:
Based on the analysis of the macro-morphology and microstructure of the cracks
the cause of the large area welding crack in the pipe base of the boiler header for 660 MW ultra-supercritical unit is studied. The results show that the welding heat input is large
the weld hardenability and reticular structure are weakened without preheating before welding and heat treatment immediately after welding
and the welding crack is produced under the action of welding restraint stress
welding residual stress and high temperature heat treatment.Improper welding technology is the main cause of welding crack.