Reason for boiler tube leakage

A leakage accident occurred during the operation of a certain boiler tube. The cause of boiler tube leakage was analyzed using methods such as macroscopic observation, chemical composition analysis, metallographic examination, scanning electron microscopy and energy spectrum analysis. The results show that there were corrosive media in the pipeline. Under the combined action of working stress and thermal stress, stress corrosion cracking occurred on the inner wall of the pipeline, and the cracks continued to expand and penetrate the wall thickness, ultimately led to a boiler tube leakage accident.