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Phenomenon: (1) The main steam or reheat steam temperature drops linearly. (2) There is a loud water impact sound or vibration in the steam pipes. (3) White steam appears or water droplets splash at the stem, flanges, and shaft seals of the main steam valve and throttle valve. (4) Load decreases, the unit emits abnormal noises, and vibration increases. (5) As the axial displacement increases, the metal temperature of the thrust bearing rises, and the expansion difference decreases. (6) An increase in the temperature difference between the upper and lower cylinders of the turbine, or an alarm is triggered. Handling principle: (1) In the event of water hammer in the unit, it should be handled as an emergency shutdown due to vacuum breakdown. (2) Make sure that the drain valves on the turbine itself and related steam pipelines are open. (3) Pay attention to monitoring parameters such as axial displacement, expansion difference, metal temperature of thrust bearings, and vibration. (4) Listen carefully to the sounds inside the turbo-generator and accurately record the coasting time. (5) If water enters the turbine due to a full water level in the heater or deaerator, the extraction steam valve should be closed immediately, the faulty heater should be isolated from the system, and drainage should be increased. (6) If water enters the turbine, causing the temperature differences between the upper and lower metal sections of the high-pressure and medium-pressure cylinders to exceed the specified limits, the vacuum should be broken immediately to shut down the machine urgently. (7) Once the turbine speed reaches zero, start continuous barring immediately. (8) When turning the rotor, pay special attention to whether the turning current increases, and record the rotor eccentricity. When the rotor is severely deformed or there is friction between the internal moving and stationary parts, and the turning gear cannot rotate the rotor, it is strictly prohibited to force it to turn. (9) After an emergency shutdown due to water hammer in the unit, it is strictly prohibited to restart it within 24 hours ； Before restarting, the turbine shall be rotated continuously for at least 6 hours, and the temperatures of the upper and lower cylinders as well as the rotor’s eccentricity must meet the specified requirements. (10) Once the steam turbine meets the starting conditions, start it. During the starting process, it is necessary to monitor parameters such as rotor eccentricity, axial displacement, expansion difference, metal temperature of the thrust bearings, and vibration to ensure they are within the specified control limits, as well as to check the drainage condition of the turbine itself and the steam pipelines ； (11) If abnormal noises or grinding sounds are detected when the turbine is restarted, the vacuum should be immediately broken to shut down the machine, and reports should be made at each level. (12) During the coasting process, if the axial displacement of the turbine, the expansion difference, vibration, the metal temperature of the thrust bearings, and the oil return temperature increase significantly, and the coasting time is markedly reduced, reports should be submitted at each stage. It is necessary to decide whether to remove the cylinder for inspection based on the condition of the thrust bearings; otherwise, startup is not permitted. (13) If abnormal noises are heard inside the turbine and friction is detected in the rotating parts during shutdown, the cylinder should be removed for inspection.