To address the corrosion failure issues in hydrogenation reaction effluent air cooler (REAC)systems, a typical process simulation model was constructed using the reverse order deduction method. This study investigated the influence mechanisms of different oil flow rates on the distribution of corrosive components within the system, ammonium salt crystallization temperature, and erosion risks. The results indicate that variations in oil flow rate do not significantly affect the aqueous distribution of corrosive components or increase the system's erosion risk. Additionally, the oil flow rate has minimal impact on the crystallization temperature of ammonium salts, meaning higher flow rates do not elevate the risk of salt formation. However, increasing the flow rate of vacuum gas oil (VGO) markedly reduces the corrosion factor (K), thereby lowering the overall corrosion risk. The VGO flow rate also has a pronounced influence on the aqueous NH?HS concentration at the air cooler outlet, whereas the effect of naphtha flow rate differs from that of diesel and VGO. Notably, raising the flow rates of diesel and naphtha increases the system pH, while increasing VGO flow rate decreases it. To mitigate corrosion risks, it is recommended to moderately increase the VGO content during crude oil processing while simultaneously boosting either the diesel content or injection water volume.