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I. Vibration problems: Since the production of high-purity benzene at the Nylon Chemical Company’s plant began in 1998, several cooling heat exchangers have experienced severe vibrations during operation, resulting in premature damage to the foundations and pipelines. The function of the condenser F-E206 is to perform gas-liquid separation on the mixed circulating gas resulting from the reaction, which contains hydrogen, benzene, toluene, xylene, and light alkanes. The material on the shell side is in a gas-liquid mixture state, with a pressure of up to 5.28 MPa and a temperature of 145.13°C; the temperature drops to 40°C after cooling℃ ； The cooling medium on the supervisor side is cooling water. If the vibration of F-E206 is not addressed promptly, it can easily lead to serious accidents such as leaks of high-pressure, flammable, and explosive circulating gases. II. Causes of vibration 1. Vibration generated during operation When the cooler F-E206 is put into use, gas is present in the cooling medium, resulting in gas slugging and thus vibration. 2. Vibration during production (1) Causes: ① Excessive amount of coolant injected ； ②Excessive coolant flow rate ； ③Production load adjustment has decreased significantly ； ④The material-side logistics flow rate decreases. In normal operation, whether in counterflow or co-current mode, the flow of the fluid and the coolant creates a temperature gradient within the heat exchanger. The presence of these factors disrupts various reasonable temperature gradients, causing the temperature of the hot fluid to drop significantly upon entering the heat exchanger, resulting in a low-temperature liquid state. This leads to a large accumulation of non-condensable high-temperature gases and still-gasified high-temperature gases in a small area, thereby causing gas slugging and severe vibration of the heat exchanger. (2) Conditions for vibration to occur during production: ① Large amount of cooling agent used ； ②The processing volume on the material side is high ； ③The temperature difference between the material before and after cooling is >100°C, which is quite large ； ④The imported material is in gaseous or gas-liquid mixed state, with complete or partial condensation phase change ； ⑤The shell side contains the high-temperature material (with a large processing volume), while the tube side holds the cooling medium, as shown in Figure 1. For the regulation of cooling water return flow, globe valves are commonly used. When the load and process parameters change significantly, it is necessary to manually adjust the cooling water return valve on-site at any time; however, delays in making such adjustments often lead to vibration. III. Treatment Methods 1. Elimination of vibrations generated during operation The vibrations that occur during operation are caused by the presence of gas on the cooling medium side, which leads to gas slugging. The treatment is relatively simple: open the exhaust valve of the coolant-side heat exchanger, and once the exhaust operation is complete, the vibration will be eliminated. 2. Elimination of vibrations generated during production: Slowly close the return water valve, and during adjustment, constantly monitor the temperature of the material after cooling to prevent excessive fluctuations, until the vibrations are eliminated. In the production units for benzene purification and cyclohexanol at Shenma Nylon Chemical Company, the vibration that frequently occurred in the cooling heat exchangers was eliminated through the aforementioned methods, with significant results. At the same time, all the process and production parameters of the heat exchanger remain unaffected, ensuring the safety and stability of production.