Abstract: The convection surperheater′s structure and 440t/h boiler system were introduced, metering and analyses were conducted for the sample of failure pipe. It was considered that the superheater blast was caused by the blockages of oxide skins, which were taken into pipes during unit startup and shutdown, and metal residues, which were left when maintenance, the blockage lead to overheating and then blasting. At last, some concrete suggestions for prevention pipe blast were proposed.

Key words: convection surperheater, desuperheater, oxide skin, short-term over-heat