Failure Analysis of Boiler Water Wall Leakage of a Thermal Power Plant
Through macroscopic analysis and microstructure observation,the internal structure,surface crack morphol-ogy and distribution of the water wall tube of a thermal power plant boiler were analyzed,and the causes of the leakage of the water wall tube were explored.The results showed that the crack originated from the inner wall of the water wall tube,and there was obvious erosion thinning phenomenon of the wall thickness in the leakage point and near the leakage point,and the thinnest part was only 320.14 μm.The microstructure of the inner wall near the leakage point was ferrite + pearlite + a small amount of carbide,and fine lamellar cracks and oxides appeared along the grain boundary.Combined with the opera-tion status of the boiler,it was speculated that there were some original defects in the bending surface of the water wall tube,and the continuous expansion of the defects caused by high temperature and high pressure was the main cause of the burst.It was recommended that strengthening the surface inspection of the pipes with large angle bending parts of the water wall and replacing the pipes that did not meet the requirements in time.
water wallfailure analysismicrostructurecrackshigh temperature and high pressureleakage
NETL
NSTL
万方数据
维普
