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Based on the corrosion mechanism of atmospheric and vacuum distillation units, benchmarking analysis, and the current situation, 5 adjustment and prevention measures have been formulated. 1. Enhance the deep desalination of crude oil by adjusting parameters such as the temperature for electrodesalination and the intensity of ultrasound, so as to reduce the salt content after desalination to 2.5 mg/L, or even below 2.0 mg/L ； 2. Monitor and mitigate corrosion at the top of the vacuum distillation column by comparing the historical trends in the hydrogen content there, and accordingly increase the dosage of corrosion inhibitors and ammonia water. Increase the frequency of analysis to at least once per day, especially for the H2 content, H2S content, O2 content, and N2 content in the depressurized gas, as well as the pH of the acidic water at the top of the depressurization tower and the chlorine content in that acidic water; this is to monitor changes in corrosion conditions and the effectiveness of corrosion inhibitors. Adjust the amount of steam used for vacuuming to ensure uniform steam distribution across all branches, prevent uneven flow of condensed steam water, and avoid insufficient washing ； 3. The pipeline at the top of the vacuum tower was recoated with a corrosion-inhibiting film to increase the amount of corrosion inhibitor injected; this amount was raised to more than twice the specified level (around 40 ppm), and recoating took approximately 15 days. Once the protective film formed by the corrosion inhibitor is in place, it can then be reduced below the agreed dosage level (about 20 ppm). If the pH is below 9.0 during this period, increase the amount of ammonia water injected; otherwise, keep the amount of ammonia water injected constant and try to inject as little as possible to prevent the formation and accumulation of ammonium salts, which could exacerbate corrosion ； 4. The process parameter control device determines the dew point temperature at the top of the vacuum tower and strives to increase both the temperature at the top of the vacuum tower and the reflux temperature of the vacuum tower, ensuring that both are at least 14 °C above the dew point temperature ； 5. The leakage detection and database establishment system conducts a comprehensive inspection of the corrosion conditions at the top of the pressure reduction tower (oil and gas pipelines, stage 3 vacuuming systems, water cooler housings, atmospheric legs). It measures the thickness of these components and stores the data for comparison; by reviewing historical thickness measurement data, changes in the corrosion rate can be identified.