Abstract: Frequent tube bursting in the high-temperature superheater of dry coke quenching (CDQ) boilers is a primary constraint on their long-term safe operation. This failure involves complex interactions between multiple factors, namely erosion and corrosion, and existing research lacks quantitative elucidation of their synergistic coupling mechanism. This study aims to reveal this coupled failure mechanism and propose effective integrated protection strategies. A multidisciplinary approach combining field case statistics, computational fluid dynamics (CFD) simulation, and microscopic material analysis was adopted. First, operational data from 106 domestic CDQ boilers were statistically analyzed to identify macroscopic failure patterns. Second, a full-scale CFD model from the CDQ outlet to the boiler inlet was established to quantitatively analyze flow field distribution and erosion rates. Finally, SEM/EDS and XRD were employed to characterize the microstructure, elemental distribution, and corrosion products of the failed tube sections, thereby revealing the microscopic corrosion mechanism. Macroscopic statistics indicate a significant positive correlation between high-sulfur coke, large-scale units and a high tube burst rate. CFD simulations quantitatively reveal a "gas flow deviation" phenomenon, causing local flue gas velocities to reach 3.5 times the average and a theoretical erosion thinning exceeding 0.5 mm/a. Microscopic analysis at an approximate wall temperature of 500 ℃ shows sulfur enrichment up to 1.33%(atomic fraction) in the corrosion layer of the failed tube section, and FeS formation is detected, confirming elemental sulfur as the key chemical factor destroying the protective oxide scale. Based on these findings, a coupled failure physical model of "mechanical scale removal-chemical corrosion-product exfoliation" was constructed, indicating that the synergistic effect leads to a failure rate far exceeding the sum of individual factors. Subsequently, an integrated protection strategy was proposed, encompassing material upgrade (TP321H/TP347H), installation of anti-wear shields, flow field homogenization modification, and source control of the corrosive medium. Following the application of this strategy in a 170 t/h CDQ boiler at a coking plant in Shanxi, the first tube burst cycle was extended from an average of 11.6 months to over 36 months, avoiding direct and indirect economic losses exceeding 6.28 million yuan per incident. This study not only provides an effective solution for the failure of CDQ boilers but also offers a universal technical pathway for preventing similar coupled failures in other high-temperature dust-laden industrial installations.