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It is necessary to integrate three methods – offline routine monitoring, online real-time monitoring, and medium analysis – to establish a comprehensive corrosion monitoring system for oil refining equipment. The specific implementation approach is as follows: First, deploy sensors in a stratified manner to cover all scenarios; identify the corrosion-prone areas within the plant’s key units, and prioritize the installation of online thickness measurement probes in high-risk areas such as those under high temperature and pressure or exposed to hydrogen. In areas subject to low-temperature electrolyte corrosion, resistive/inductive/electrochemical probes should be used to enable 24/7 monitoring of corrosion rates. For areas prone to erosion such as elbows, tees, and locations behind control valves, ultrasonic thickness measurement points are installed; corrosion coupons made of the same material are used alongside these points to regularly verify the accuracy of the online monitoring data. II. Medium tracing and advance warning: Online analyzers for pH, total iron, chloride ions, and sulfides are installed at key locations such as the top of atmospheric and vacuum distillation towers and hydrocracking units to monitor in real time any changes in the corrosiveness of the process media. Meanwhile, regular sampling is conducted to determine the levels of sulfur, acid, chlorine, and nitrogen in crude oil, thereby enabling early detection of corrosion risks at the source. Dynamic adjustment of anti-corrosion parameters for processes such as injection and water injection is carried out based on the results of medium analysis, thereby advancing the point at which corrosion control is implemented. III. Data integration and closed-loop control: A unified corrosion monitoring data platform is established to integrate multi-source data from online probes, fixed-point thickness measurements, and medium analysis; it automatically calculates the corrosion rate and triggers alarms in real time for locations where the values exceed the specified limits. During the shutdown for maintenance, historical monitoring data is reviewed using methods such as visual inspections and penetrant testing, in order to optimize the subsequent monitoring layout, thus creating a sustainable closed loop of \"monitoring–analysis–optimization\".