Burst Failure of the Ceiling Tubes in a Coke Dry Quenching Furnace

By analyzing the macro morphology, microstructure observation, nonmetallic inclusions, chemical composition of substrate, component and phase analysis of the attachment on the surface, the reason for burst failure of the ceiling tubes in a coke dry quenching (CDQ) furnace was discussed. The results showed that the ceiling tube near the inner wall of the furnace without mask on the side of bursting was severely thinned by the accumulation and erosion of flue gas. In the environment of flue gas with high temperature, the oxide scale was easily formed. The oxide scale on the external surface was flaked off by corrosion and then regenerated. Circularly, the thickness of tube was reduced and the strength decreased further. Meanwhile, the steel aging of tube caused the reduced mechanical properties because of long-term service at high temperature. Finally, the ceiling tube burst due to over the limit pressure inside the tube.