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Technical measures to prevent bending of the turbine shaft: 1. Before starting the turbine, it is necessary to ensure that the shaft’s eccentricity is less than 0.076 mm, and that the shaft’s vibration level does not exceed 0.02 mm of the original value. When starting the turbine after a major overhaul, it is necessary to use a dial indicator to measure the runout of the main shaft on each bearing oil baffle; this value must be less than 0.0254 mm. 2 Temperature difference between the upper and lower sections of the 2-cylinder engine (referring to the exhaust areas in the upper and lower parts of the high-pressure cylinder at the adjustment end) ； It is prohibited to start the steam turbine unit if the exhaust temperature at the upper and lower ends of the medium-pressure cylinder exceeds 42°C. The temperature at the inlet of the main steam valve should have a superheat of at least 56°C. The cold and hot start-ups of Unit 3 shall be carried out in accordance with the charts and curves for \"main steam parameters during start-up\", \"rotor heating procedures for cold start-up\", and \"recommended values for hot start-up\". 4 Under any circumstances, the steam temperature at the first stage of the turbine shall not be 56°C lower or 111°C higher than the metal temperature at the first stage. 5 During hot start-up, steam should be supplied to the steam seal first and then vacuum should be created. Before supplying steam to the steam seal, it is necessary to drain all water thoroughly, and steam can only be supplied after confirming that there is no water in the pipes. 6 The steam supplied to the steam seal must have a superheat of over 14°C, while the temperature of the steam supplied to the low-pressure steam seal should be maintained between 121 and 177°C. 7 Steam supply to the steam seal is prohibited before the unit is turned. 8 When the steam supply temperature to the high and medium pressure steam seals is less than 150°C, or when the temperature difference between the steam supply temperature to the steam seals and the end wall temperature of the high-pressure cylinder at the regulated end is less than 85°C, the steam injection for the steam seals should be turned off. 9 During the unit startup process, warming-up is carried out in accordance with the curves for \"maintaining the recommended turbine speed,\" \"heating procedures for a cold rotor,\" and \"recommended values for hot-starting.\" The warming-up time starts to be counted from the moment the inlet temperature of the medium-pressure cylinder reaches 260°C. 10 During the startup of the unit, a dedicated person must monitor the vibration of each bearing of the turbine unit; the shaft vibration of the turbine should be below 0.125 mm. When passing through the critical speed, if the bearing vibration exceeds 0.1 mm or the relative shaft vibration exceeds 0.254 mm, the machine should be stopped immediately by shutting down the brakes. Forcing the machine past the critical speed or warming it up by reducing speed is strictly prohibited. During the operation of Unit 11, the bearing vibration shall not exceed 0.03 mm, or the relative shaft vibration shall not exceed 0.08 mm; if these values are exceeded, measures must be taken to eliminate them. If the relative shaft vibration exceeds 0.254 mm, the machine should be stopped immediately by shutting down the brakes ； When the bearing vibration changes by ±0.015 mm or the relative shaft vibration changes by ±0.05 mm, the cause should be identified and eliminated. If the bearing vibration suddenly increases by 0.05 mm, the machine should be stopped immediately by shutting down the brake. 12 According to the Centralized Control Operation Procedures, once water hammer in the turbine is detected, the machine should be stopped immediately by shutting down the brakes. 13 All level protections for the high and low pressure heaters as well as the deaerator must be in operation and regularly tested. In the event of a heater leak, the operation of the heater must be stopped immediately and the extraction check valve closed. 14 After shutdown, cranking should be initiated promptly. If the cranking current is higher than the normal value, if there is vibration, or if unusual noises are heard, relevant departments and supervisors should be informed immediately so that the cause can be identified and addressed promptly. In the event of severe friction in the steam seal, position the high point of the rotor at its highest position, shut off the cylinder drain valve to maintain a temperature difference between the upper and lower cylinders, and monitor the rotor’s bending degree. Once it is confirmed that the rotor’s bending degree is normal, manually rotate the rotor 1800 degrees to straighten it. When the turntable will not move, it is strictly prohibited to use a crane to force it to turn. When turning the rotor is temporarily halted due to a fault after shutdown, the change in the rotor’s bending degree should be monitored; if the bending degree is significant, the rotor should be turned manually by 1800 degrees, and continuous rotation should be resumed as soon as normal operation is achieved. During the startup, operation, and shutdown of Unit 15, the \"Technical Measures to Prevent Cold Steam and Cold Water from Entering the Turbine\" must be strictly followed. When opening and closing various steam and water valves, care must be taken to prevent steam, cold air, drain water, and condensate from entering the extraction pipes, steam leakage pipes, or drain pipes and returning to the cylinder. 16 The local water level gauges of the deaerator and heaters, as well as the water level indication on the CRT, should be checked once per shift.