1. All auxiliary equipment and systems are operating normally, and there is no prohibition on starting.
【Interpretation】The failure of the lubricating oil pump, the top shaft oil pump or the cranking device cannot make the unit start normally. In accordance with Article 3-6-23 of the Technical Management Regulations of the Electric Power Industry.
2. The turbine-generator set has been continuously cranked for more than 12 hours, and the cranking current and rotor eccentricity meet the requirements, and the expansion difference and axial displacement of high, medium and low pressure cylinders are normal.
【Interpretation】The continuous crank of the steam turbine can eliminate the residual stress of the rotor, reduce the thermal bending, and the cranking current, rotor eccentricity meet the requirements, and the expansion difference and axial displacement are normal, indicating that the rotor has no bending, dynamic and static friction.
3. The relevant parameters should be stable at the following values.
a) The main steam pressure is 4.0MPa
b) Main steam temperature 380°C
c) Reheat steam pressure 1.5MPa
d) Reheat temperature 360°C
The choice of main steam pressure and reheat pressure can meet the requirements of the stroke smoothly through the critical speed to the constant speed, with partial load, and can smoothly switch from the medium pressure cylinder to the high and medium pressure cylinder combined steam intake, the steam temperature is 360~380 °C, which is about 110~130 °C higher than the saturation temperature of 250 °C under the steam at 4.0MPa, and the heat release coefficient is small, so as to avoid thermal shock to the unit. According to the "Alstom 330MW Steam Turbine Manual"
e) 凝汽器真空>82KPa
【Interpretation】Vacuum 70KPa or more should not be too high or too low, steam condenses in the steam turbine during the flushing process, the vacuum will be reduced to different degrees, if the vacuum is too low, there will be a danger of making the atmospheric exhaust valve action at the moment of impulse, and the vacuum is low so that the exhaust temperature rises, resulting in the relaxation of the copper tube expansion port, resulting in leakage, the vacuum is too high is not conducive to the warm-up and reaches too high vacuum to prolong the start time.
f) EH油压 12.4~14.6 MPa
【Interpretation】The selection of EH oil pressure 12.4~14.6 MPa is based on the dynamic characteristics of the speed control system, to ensure that the main valve and speed control valve can act quickly, the slowness rate is small, and the safety and stability of the system can be guaranteed.
g) EH油温 35℃～50℃
【Interpretation】EH oil temperature of 35°C~50°C is because the EH oil quality will deteriorate rapidly when the EH oil temperature is too high, and the oil temperature is too low to increase the viscosity of EH oil and overload the EH oil pump, which affects the action speed of the speed control system.
h) 润滑油压 0.15～0.2MPa
【Interpretation】The choice of lubricating oil pressure of 0.15~0.2MPa is determined according to the rotor weight, speed, the structure of the bearing and the viscosity of the lubricating oil, so as to ensure that a good oil film is formed between the bearing and the journal during operation, and there is enough oil to cool the bearing.
i) 润滑油温 35°C~40°C
If the viscosity of the oil is lower than 30 °C, the cold start impulse time is long, the friction power of the bearing increases, the bearing load capacity decreases, the oil film works unstable and may cause the unit to vibrate. According to Article 75 (3) of the ministerial regulations, "the oil temperature shall not be lower than 30°C before the speed increase." ".
j) The temperature difference between the upper and lower parts of the high and medium pressure cylinders < 90°C, and the metal temperature at each point is normal.
If it is greater than 90 °C, the radial clearance at the bottom will disappear, and it is easy to make the dynamic and static part friction, especially when the rotor is hot bending, the impulse will be greater in the danger of friction of the dynamic and static parts, and the temperature difference between the upper and lower cylinders is too large, which is often the original factor causing the bending of the large shaft. In accordance with the provisions of Article 10.1.2.3 of the 25 key requirements.
k) Contact the chemical laboratory to test that the steam quality meets the requirements.
【Interpretation】Unqualified steam quality will cause scaling of steam turbine blades, which will reduce the efficiency of the steam turbine, increase the axial thrust, unbalance the mass of the rotor, and increase the vibration of the steam turbine.
l) Confirm that all steam traps are open.
【Interpretation】When the steam turbine is rushed, it is the heating process of the steam turbine, and the water generated must be discharged in time, otherwise the temperature difference of the metal will become larger, affecting the thermal expansion, and causing water shock in serious cases.
m) Check to confirm that the water spray valve (303081) (403081) of the low-pressure cylinder is open.
【Interpretation】The amount of steam entering the low-pressure cylinder in the early stage of the flushing is very small, due to the long blades of the low-pressure rotor blades, the heat generated by the blower friction is also more, so that the low-pressure cylinder is also heated and expanded, and the low-pressure cylinder needs to be opened to reduce the temperature of the low-pressure cylinder and make the low-pressure cylinder expand within the normal range.
n) Check and confirm that all the protection inputs of the turbine generator set are normal.
【Interpretation】All the protection inputs of the steam turbine generator set are used to ensure that the steam intake of the steam turbine can be quickly cut off and the operation of the unit can be stopped in the case of abnormal impulse, so as not to cause serious damage to the equipment and achieve the purpose of automatically protecting the safety of the equipment.
5. After the punching conditions are satisfied, report the unit length and value length, receive the punching command, and record the main parameters before the punching, such as the main and reheat steam pressure, temperature, axial displacement, vacuum, expansion difference, lubricating oil pressure, oil temperature, etc.
【Interpretation】Record the parameters before flushing for analysis and comparison.
6. On the DEH "Speed Control" screen, press the "Medium Cylinder Control" button to check that the "Medium Cylinder Control" light is on.
【Interpretation】The control button of the medium cylinder is to use the medium pressure cylinder to rush, and control the speed and load of the steam turbine by controlling the opening of the medium pressure speed regulating valve
7. Press the "target value" on the DEH, set the target speed of 1000 r/min, and the rising rate will be automatically given by the DEH after calculating the metal temperature of the middle wall of the upper flange of the medium pressure inner cylinder.
【Interpretation】When the cold slip parameter is started, it should first be rushed to 1000r/mim for warm-up, 1000r/min warm-up is a medium-speed warm-up, and the main reason for choosing this speed warm-up is to avoid the critical speed and prevent it from falling into the resonance zone and causing strong vibration. In addition, it is also to increase the rotor temperature to prevent low-temperature brittle damage and excessive thermal stress, and the medium-speed warm-up must be sufficient, otherwise the metal temperature rise rate may be too high during the high-speed warm-up, and it is also the warm-up inspection stage.
8. Press the "Progress" button, the "Progress" light is on, the "Keep" light is off, pay attention to the medium pressure door slowly open, increase the speed, when the actual speed is greater than 140r/min, the check turning device should automatically trip and exit the operation, otherwise it should be stopped immediately, and the fault should be eliminated and re-flushed.
【Interpretation】After pressing the "progress" button, the medium pressure adjusting door is opened and starts to rotate, when the speed of the steam turbine is greater than 140r/min, the cranking device should automatically trip, otherwise the steam turbine spindle drives the cranking device, which will cause serious damage to the cranking device.
9. After the main steam pressure drops after the flushing, the high side pressure reducing valve (300309) (400309) should be adjusted in time to increase the amount of fuel, stabilize the main steam pressure, and the high-pressure bypass should be converted to a constant pressure control mode.
【Interpretation】After the steam turbine is impulsed, the steam inlet of the steam turbine will reduce the pressure, and the boiler should be in contact with the boiler, and the advance amount should be mastered, and the parameters should be controlled to prevent the parameters from fluctuating too much.
10. When the speed rises to 600r/min, you can press the "hold" button, "carry out" the light, "keep" the light on, stop the unit from rising, and conduct a comprehensive inspection of the unit.
【Interpretation】When the speed of the steam turbine is low, maintain the speed to carry out a comprehensive inspection, find out the factors affecting the start of the unit in time, and eliminate them in time to prevent the expansion of faults.
11. Listen to the normal sound of the unit, and if necessary, it can be tripped for friction inspection.
【Interpretation】Listen carefully to the internal sound of the unit through listening sticks and other tools, check whether there is friction in the dynamic and static parts, and eliminate the influence of the steam inlet sound by hitting the brake if necessary.
12. Check the steam turbine body, the pipeline should be free of water hammer and vibration, and there should be no abnormality in the water discharge system.
【Interpretation】Check to prevent water hammer and vibration caused by warm-up, insufficient heating pipes, poor hydrophobicity, and excessive heating.
13. Check that the metal temperature, oil return temperature, bearing vibration, axial displacement, differential expansion, etc. are all within the normal range.
【Interpretation】After the steam turbine is impulsive, strengthen the inspection of the bearing metal temperature, oil return temperature, bearing vibration, axial displacement, and differential expansion, and analyze the cause of the change in time and eliminate it in time if abnormal changes are found.
14. Pay attention to the hydrogen pressure, hydrogen temperature, sealing oil pressure, and sealing oil hydrogen/oil pressure difference of the generator are normal.
【Interpretation】After the steam turbine is impulsive, strengthen the inspection of the hydrogen pressure, hydrogen temperature, sealing oil pressure, and sealing oil hydrogen/oil pressure difference of the generator, and analyze the causes of the changes in time and eliminate them in time if abnormal changes are found.
15. Pay attention to the changes in the temperature and temperature rise of each point of the high and medium pressure cylinders and the temperature difference between the upper and lower cylinders.
【Interpretation】After the steam turbine is impulsive, strengthen the inspection of the temperature, temperature rise and temperature difference between the upper and lower cylinders of the high and medium pressure cylinders of power generation, and analyze the causes of the changes in time and eliminate them in time if abnormal changes are found.
16. Pay attention to the vacuum and water level of the condenser, the deaerator and the water level of the low addition.
【Interpretation】After the steam turbine is impulsive, strengthen the inspection of the condenser vacuum, water level, deaerator and low water level, and analyze the cause of the change in time and eliminate it in time if abnormal changes are found.
17. Pay attention to the changes in lubricating oil pressure, EH oil pressure, oil temperature and oil tank level.
【Interpretation】After the steam turbine is impulsive, strengthen the inspection of lubricating oil pressure, EH oil pressure, oil temperature, and oil tank oil level, and analyze the causes of abnormal changes in time and eliminate them in time.
18. After checking that everything is normal, press the "Progress" button, when the speed reaches 1000r/min, the "Progress" light will be turned off, the unit will automatically stop the speed increase, keep the speed at the speed for 30 minutes and check the above items. (The turbine is not allowed to increase until the metal temperature of the flange under the high-pressure outer cylinder reaches 190°C, and the warm-up is over)
【Interpretation】600r/min after a comprehensive check is normal, it rises to 1000r/min for medium-speed warm-up, and the main reason for choosing this speed warm-up is to avoid the critical speed and prevent it from falling into the resonance zone and causing strong vibration. In addition, it is also to increase the rotor temperature to prevent low-temperature brittle damage and excessive thermal stress, and the medium-speed warm-up must be sufficient, otherwise the metal temperature rise rate may be too high during the high-speed warm-up, and it is also the warm-up inspection stage.
19. When the metal temperature of the flange under the high-pressure outer cylinder ≥ 190 °C, check that the high-pressure cylinder back-up heater (300308) (400308) should be automatically closed, the high-pressure cylinder vacuum valve (345037) (445037) will be automatically opened, and the high-pressure backstop door (300306) (300307) (400306) (400307) should be forcibly closed to confirm that the high-pressure cylinder is in a vacuum state.
The purpose of 1000r/min warm-up is to increase the rotor temperature to prevent low-temperature brittle failure and excessive thermal stress, when the rotor metal temperature is reduced to less than FATT, the impact toughness of the material decreases a lot and brittleness appears. Because the transient temperature distribution of the rotor is complex, the rotor temperature is not suitable for measurement, so the corresponding cylinder temperature is generally taken as a reference. When the metal temperature of the flange under the high-pressure outer cylinder ≥ 190 °C, it can be judged that the corresponding high-pressure rotor temperature has exceeded the low-temperature brittle transition temperature, and the high-pressure cylinder has been fully heated at the same time, and the high-pressure cylinder will close the high-exhaust backstop door and the inverted warm-up door in order to prevent the heat generated by the friction of the rotor blast when the speed continues to rise, and open the vacuum door to ensure the vacuum state in the high-pressure cylinder.
20. At the end of the warm-up, press the "target value", set the target speed of 3000r/min, press the "progress" button, and the steam engine will continue to rise.
【Interpretation】After the end of the medium-speed warm-up, the high-pressure cylinder is cut from the inverted heating state to the vacuum state, and then continues to rise to the rated speed.
21. When the speed reaches 1050 r/min, check that the high-pressure main valve (300300) (300301) (400300) (400301) should be automatically closed, and the high-discharge backstop valve (300306) (300307) (400306) (400307) and the high-pressure cylinder vacuum valve (345037) (445037) are in correct position.
【Interpretation】Prevent the high-pressure speed control valve from not being tight, which will affect the vacuum effect of the high-pressure cylinder.
22. During the speed increase, a comprehensive inspection should be carried out according to the specified items, and the vibration changes of each watt journal should be checked.
【Interpretation】With the increase of the speed, the oil film of each bearing is gradually formed, and the corresponding position of the journal will also change to a certain extent, and it will also pass the critical speed, which will affect the change of the vibration of the journal, so it is necessary to focus on checking the vibration of the journal. When passing through the critical speed zone during the rushing process, there is a prompt of "passing the critical speed" in the DEH screen, and the lifting rate is automatically changed to 500r/min at 50 revolutions before and after passing through the critical speed zone.
23. When the speed reaches 2900r/min, check the crank motor and the top shaft oil pump will stop automatically; when the speed reaches 3000r/min, the "conduct" light will be off, and the "keep" light will be on, check that the main oil pump is working normally, the outlet oil pressure is normal, the lubricating oil pressure will be normal, and the AC lubricating oil pump will be stopped. Note: The temperature and vibration of each bearing of the steam turbine should be normal.
【Interpretation】When the speed reaches 2900r/min, the crank motor and the top axle oil pump will automatically stop when the top axle crank function group is put in, and when the speed rises to 2900r/min during the rushing process, the lifting rate will be automatically changed to 50r/min, and when the steam turbine speed reaches 3000r/min, the main oil pump has been working normally, and the AC lubricating oil pump can be stopped after checking normal.
24. Stay for 20 minutes at the speed of 3000r/min to warm up the engine, and conduct a comprehensive inspection of the steam turbine unit.
【Interpretation】The speed of the steam turbine reaches 3000r/min and stays for 20 minutes for high-speed warm-up, which reduces the temperature difference of each part and reduces the thermal stress, so that the cylinder and rotor can be fully heated and expanded.
25. The speed of the machine is 3000r/min, and the following tests are done after the parameters are stable and normal:
a) Lubricating oil pressure switch test.
[Interpretation] see the host test section
b) Vacuum pressure switch test.
[Interpretation] see the host test section
26. In the process of steam turbine speed increase and warm-up, parameters such as steam pressure, steam temperature and water level should be kept stable as much as possible.
【Interpretation】Excessive fluctuations in steam temperature will cause excessive thermal stress in the steam turbine, and fluctuations in steam pressure will affect the speed of the steam turbine and make the speed of the steam turbine unstable. Unstable drum water levels may cause the boiler MFT protection to act and trip the turbine. Therefore, each parameter should be controlled and kept stable.
27. The temperature of the steam entering the steam turbine is at least 80 °C superheat.
【Interpretation】Prevent the steam entering the steam turbine from falling below the saturation temperature after expansion and work, and the water content in the steam will cause serious consequences such as water shock.
28. In the process of speed increase, you can press the "hold" button to maintain the speed when necessary, but it is strictly forbidden to stay in the critical speed area.
【Interpretation】The critical speed should be rapid and stable to prevent staying at the critical speed and falling into the resonance area, causing vibration damage, according to Article 10.1.4.2 of the 25 key requirements.
29. The lifting rate is determined according to DEH according to the metal temperature of the middle wall of the upper flange of the medium pressure inner cylinder (GMA TE 038):
(GMA TE 038) <150°C., $100r/min.. 150°C< (GMA TE 038)
【Interpretation】The cold start of the steam turbine is a heating process, which is bound to produce thermal stress in the metal, the steam enters the steam turbine after the steam turbine is impulsed, and the thermal stress is controlled by adjusting the speed rate to indirectly control the metal temperature rise rate, and the corresponding temperature rise rate is calculated by monitoring the temperature of the upper flange of the medium pressure cylinder, which can not only ensure that there is no excessive thermal stress but also can rise to the rated speed as soon as possible, and shorten the start-up test. According to the "Alstom 330MW Steam Turbine Manual"
30. Pay attention to the fact that there is no water impact and abnormal vibration phenomenon in the steam turbine body and pipeline, and the steam turbine water evacuation system is normal;
【Interpretation】Check to prevent water hammer and vibration caused by warm-up, insufficient heating pipes, poor hydrophobicity, and excessive heating.
31. Pay attention to monitor the vibration and watt temperature of each bearing in the process of rushing and speeding.
【Interpretation】With the increase of the speed, the oil film of each bearing is gradually formed, and the corresponding position of the journal will also change to a certain extent, and it will also pass the critical speed, which will affect the change of the vibration of the journal, so it is necessary to focus on checking the vibration of the journal. As the speed increases and the load increases, the heat generated by the friction between the oil film and the journal also increases, so it is necessary to pay attention to the monitoring of the watt temperature.
