Abstract:An analysis is made and countermeasures are given on the large area exfoliation of the oxide scale at the rear platen superheater of the 2 × 660 MW Ultra-supercritical boilers, which are made of domestic TP347HFG austenitic stainless steel, and have just been put into operation for about 6 months.It is considered that the manufacturing process of domestic TP347HFG austenitic stainless steel needs to be optimized and improved.It is also recommended that domestic TP347HFG austenitic stainless steel for elevated temperature heating pipe of the ultra-super critical boiler must be treated with internal surface shot peening to prevent pipe explosion accidents caused by oxide exfoliation.In addition, the non-automatic feeding of feed water may be another important reason for the oxidation scale to fall off early.