1. What are the operating criteria for the chilled water system?
Answer: (1) The backwashing of the generator stator coil can only be carried out when the unit is stopped. The water cooling system must be adjusted to forward flow before the unit starts.
(2) During the operation of the generator, the stator coil must be maintained to run with water, otherwise it is not allowed to be connected to the grid with load.
(3) Before the generator is put into normal operation, the generator should be filled with hydrogen first, and then water should be passed to the stator coil, and the stator cooling water pressure should be adjusted to be at least 0.035Mpa lower than the hydrogen pressure of the generator.
(4) When the generator is loaded, there must be cooling water circulating in the stator winding, under normal circumstances, once the stator coil is watered, the hydrogen pressure in the generator must be maintained higher than the water pressure to prevent the potential danger of water leakage. However, when the sealing oil system fails and can only maintain low hydrogen pressure operation, the minimum water pressure must be maintained not less than 0.15MPa, even if the water pressure is greater than the hydrogen pressure, short-term operation is allowed, but long-term operation is not recommended.
(5) It is strictly forbidden for carbon dioxide to enter the stator cooling water.
2. What are the hazards of generator oil inlet and air hydrogen side string oil?
Answer: 1) After the generator is oiled, the water-containing oil droplets are easy to form a breakdown discharge channel on the surface of the insulation and end lashing structure at the end of the generator, which will also cause the dielectric performance of hydrogen to deteriorate, resulting in the decline of insulation, and seriously threatening the safety of the generator. 2) The oil inlet of the generator and the channeling oil on the air and hydrogen sides precipitate the water in the lubricating oil into the hydrogen, which increases the humidity of the hydrogen in the engine, which is one of the important reasons for the high hydrogen humidity of the large steam turbine generator, and is also the main reason for the hydrogen-induced cracks in the generator guard. The increase of hydrogen humidity also increases the ventilation loss of the motor and reduces the operating efficiency. 3) The channeling of the air-side and hydrogen side sealing oil makes the dissolved air in the lubricating oil enter the hydrogen system of the generator through the oil exchange, resulting in the reduction of hydrogen purity, and the hydrogen is also carried out of the machine by the airside oil, and the hydrogen replenishment frequency is high, which affects the safe and economical operation of the unit.
3. What are the main items that should be monitored after the unit is shut down?
Answer: 1) The temperature difference between the upper and lower cylinders, the exhaust temperature of the low-pressure cylinder, the eccentricity of the rotor and other parameters. 2) Listen regularly to the sound of the steam engine moving and static friction. 3) The operation of the cranking device. If the crank cannot be put into operation for some reason, the manual crank will be used immediately, and the rotor will be rotated 180 degrees every 15-20 minutes, and the continuous cranking operation will be resumed as soon as possible. If the crank trips in operation, it should be immediately tried to cast once, if the input is unsuccessful, and confirm that it is caused by large resistance, it indicates that the rotor has been bent, should be changed to a regular 180 degrees of manual cranking, it is strictly forbidden to forcibly put into the continuous crank, while checking the cylinder drain system, to find the cause. 4) Pay attention to the normal operation of the main oil system, and pay attention to the normal operation of the sealing oil system before the hydrogen is replaced. 5) Confirm that the host idle time is normal, otherwise the cause should be found.
4. What are the requirements for the condenser?
Answer: 1) It has a high heat transfer coefficient and a reasonable tube bundle arrangement. 2) The condenser body and vacuum tube system should have a high degree of tightness. 3) The steam resistance and condensate supercooling degree should be small. 4) The water resistance should be small. 5) The oxygen content of the condensate should be smaller, 6) It is easy to clean the cooling water pipe. 7) Easy to transport and install.
5. How to judge that the filter screen of the stator water main circuit is blocked?
Answer: 1) The outlet pressure of the stator pump increases, and the water flow rate of the stator decreases; 2) The pressure difference is seriously blocked, and the alarm is issued.
6. What measures have been taken to balance the axial thrust of the unit?
Answer: 1) The high and medium pressure cylinders are arranged in the opposite direction, 2) The low pressure cylinders are symmetrically arranged along the steam inlet blades, that is, the flow is divided, 3) The high and medium pressure cylinders are balanced pistons, and the remaining axial thrust is borne by the thrust bearing.
7. How can I tell if a heater is leaking?
Answer: 1) The end difference of the heater increases, 2) The water temperature of the heater outlet decreases, 3) The hydrophobic water level rises or the heater is full of water, 4) When the leakage is serious, the pressure on the steam side increases, and the shock vibration occurs in the inlet pipe and the trap.
8. How to restore the maintenance measures of the stator water cooler?
Answer: 1) Check the cooler water discharge door is closed;2) Manually fill the cooling water tank to the high water level;3) Open the water injection door of the stator water side of the cooler, and the water injection door leading to the water side of the stator of the running cooler must be closed tightly;4) When the air door has continuous water outflow, it indicates that the cooler water is full, pay attention to the water door, air door;5) Slowly open the water side entrance door of the stator, pay attention to the stator water flow, until the pressure is consistent with the pressure of the running side;
9. What items should be checked when the stator water temperature at the inlet of the generator is high?
Answer: 1) Check whether the cooling door of the stator water cooler is fully open;2) Check whether the inlet door of the stator water side of the standby stator water cooler is closed tightly, and whether there is stator water that has not been cooled and directly enters the generator;3) Check whether the cooling water temperature is normal, whether the temperature control valve of the constant cold water and the closed cooling water of the fixed cold water are abnormal; 4) Check whether the generator is running normally; 5) Whether the water level of the fixed cold water tank is normal; whether the heating of the water of the fixed cold water is mistakenly cast; The outlet temperature is high Check the items: 1) Check the stator water flow; 2) Whether it is overloaded; 3) If the inlet temperature is normal, it may be the generator stator coil fault。
10. What is the reason for the increase in the conductivity of stator water?
Answer: 1) Ionizer failure, resin failure, 2) Cleaning the filter screen caused by fouling, 3) Supplementary water quality is unqualified.
11. What should I pay attention to when dealing with gas replacement?
Answer: 1) The sealing oil system must ensure the reliability of oil supply, and the oil/air pressure difference is maintained at about 0.056MPa. 2) The generator rotor is at a standstill. (Gas replacement is also possible in the crank state, but the gas consumption will be greatly increased.) 3) When replacing hydrogen, it is necessary to pay attention to the oil level of the float fuel tank and the oil level of the generator oil and water detector. Strictly prevent the occurrence of oil ingress and hydrogen running accidents in the generator. 4) Attention must be paid to the speed of hydrogen charging and discharging when gas is replaced. 5) Attention must be paid to adjusting the sealing oil pressure when replacing to prevent oil from entering the generator. 6) It is strictly forbidden to work around the hydrogen during hydrogen replacement. 7) When filling carbon dioxide bottles, anti-freezing measures must be taken for the pipeline. 8) Before gas replacement, the analytical instrument in the gas replacement plate should be calibrated, and the CO2 and H2 purity values indicated by the instrument should be compared with the test results, and the error should not exceed 1%.
12. What should be paid attention to when recovering the stator pump?
Answer: 1) stop running the pump after starting the standby constant cooling water pump normally; 2) close the entrance and exit doors of the stator water pump; open the pump body and pipeline discharge door; 3) the stator pump motor is energized; 4) hang warning signs on each door and the motor body; when recovering, the constant cooling water tank must be manually replenished to a high water level, and then slowly open the pump outlet and entrance doors, pay attention to monitoring the water level of the fixed cooling water tank.
13. What measures can be taken if the exhaust temperature of the low-pressure cylinder reaches the alarm value during normal operation?
Answer: 1) Increase the vacuum 2) Reduce the reheating temperature, and the load can be increased in the case of low load, so that it exceeds more than 15% of the rated load. 3) If it is not under the condition of grid connection, the steam turbine can be slowed down to the warm-up speed. 4) If the speed is already warmed up, it can be returned to the speed of the car. 5) Put the exhaust cylinder water spray device into use.
14. During the operation of the unit, the smoke exhaust fan of the main oil tank stops running, what abnormalities may be caused?
Answer: 1. The oil return of each bearing is not smooth, and the oil leakage of individual bearings. 2. Water accumulation at the bottom of the main fuel tank;3. The hydrogen in the main oil tank cannot be discharged, resulting in hydrogen explosion.
15. How to deal with the drop in hydrogen pressure in the generator?
Answer: 1. Confirm whether the table is correct on the spot. 2. Check the working condition of the sealing oil system. 3. Check whether each hydrogen system is leaking or the valve is opened by mistake. 4. Send someone to replenish hydrogen to the generator to maintain the rated pressure. 5. If the hydrogen pressure cannot be maintained, apply for a fault shutdown. 6. When the hydrogen leakage is serious, attention should be paid to prevent hydrogen explosion, and the fire brigade should be notified in time to prevent accidents.
16. As the steam pressure increases, what are the main problems facing the reliability of ultra-supercritical steam turbines?
Answer: 1. The stress of pressure-bearing components such as cylinders, nozzle chambers, valve housings, and steam guide pipes increases, and they face severe strength and life problems; 2. The density of the main steam is high, the specific volume is small, and the eccentricity and gap asymmetry of the high-pressure rotor produce steam force, and the steam flow excitation is easy to cause shaft instability; 3. The pressure difference between the various levels of the steam turbine and the pressure difference of the shaft seal also increases, and the steam leakage of the separator seal, blade top seal, shaft seal and other components increases.
17. How do I prevent the sealing oil from getting inside the generator?
Answer: 1. Ensure that the defoamer tank and the hydrogen side return tank are free of debris to prevent debris from blocking the oil circuit. 2. Before putting into operation, exit the hydrogen side and return the fuel tank, and the upper and lower four thimbles make the two float valves in a free state. 3. The alarm system is not perfect, and it is forbidden to put into operation the sealing oil. If there is an abnormal alarm found during operation, it should be notified in time to confirm and deal with it. 4. Strengthen inspections, inspect the oil level of the defoaming tank and the oil level of the hydrogen side return tank as the key monitoring during operation, deal with abnormal working conditions in a timely manner, and prevent oil ingress. 5. When the main engine lubricating oil system is put into operation and the sealing oil system has not yet been put into operation, it must be confirmed that the isolation doors and bypass doors before and after the airside sealing oil standby differential pressure valve are closed.
18. How to do the maintenance measures of stator water cooler, and what should I pay attention to?
Answer: 1. Check that the standby cooler is full of water, otherwise start the condensate pump and use the fixed cooling water to fill it and empty it; 2. Open the entrance and exit doors of the standby cooler cooling water and stator water. 3. Slowly close the inlet and outlet doors of the cooling cooler and the cooling water door, and pay attention to the flow rate of the cooling water and the water level of the cooling tank. 4. Open the chilled water and cooling water discharge door of the cooler on the deactivated side, and pay attention to the water level of the chilled water tank and the closed expansion water tank;
19. How to deal with the fire of the main engine oil system during the operation of the unit?
Answer: 1. If the main engine oil system is on fire and the fire does not pose a serious threat to the unit, the operation of the unit should be maintained under the premise of ensuring the safety of the unit, and the fire should be extinguished at the same time. Otherwise, it should be shut down urgently. 2. When the main engine oil system is on fire, the supply of lubricating oil should not be interrupted before the turbine generator rotor is not stopped. After the rotor is completely stopped, it is decided whether it is necessary to stop the operation of all main engine oil pumps according to the actual situation, and even open the accident oil drain valve of the main oil tank to discharge the oil urgently, so as to avoid the expansion of the fire and endanger the safety of the main equipment. 3. When the generator catches fire, the hydrogen should be discharged urgently after the unit is opened, and carbon dioxide should be charged. 4. When using water or foam fire extinguishers in fire extinguishing, attention should be paid to preventing water or fire extinguishing agents from entering the insulation of live equipment and high-temperature equipment and pipelines, causing equipment damage.
20. What are the benefits of oxygenating water?
Answer: 1. Effectively prevent the scaling of the heating surface of the boiler 2. Make the regeneration cycle of the fine treatment mixed bed longer 3. Save costs
21.What is the structure and function of DAS seal?
Answer: In the DAS vapor seal structure, the gap between the DAS tooth and the rotor is smaller than that between the conventional tooth and the rotor, and the DAS tooth adopts a wide tooth structure. DAS seals reduce seal wear by replacing two conventional seal teeth with two wear protection teeth (DAS teeth) in each seal arc. In the process of starting and stopping the steam turbine, due to the influence of the critical speed, the DAS tooth first contacts with the rotor to produce friction, and then compresses the spring on the back of the steam seal ring to produce a concession, which not only reduces the wear of the DAS tooth, but also protects the conventional tooth from friction with the rotor. DAS tooth adopts wide tooth structure, the material is also wear-resistant, even if it is abrasive with the rotor, its wear is very small, and the leakage of the whole steam seal is smaller than that of the traditional design, so that the problem of large steam leakage of steam seal in various parts of the steam turbine can be solved.
22. How to protect the ionizer after the stator water system is stopped?
Answer: The resin in the stator water ionizer cannot be in contact with the atmosphere, so the ionizer should be isolated when the stator water system discharges.
23. What is the function of the anti-siphon pipe?
Answer: The generator is arranged in the running layer, and the stator cooling equipment is at 0 meters, which will cause siphoning when the cooling water at the outlet of the generator flows down from the running layer. Because the siphon pressure is lower than the atmospheric pressure, it is easy to cause the cooling water vaporization at the outlet end to form blockage, which affects the cooling effect. Therefore, an anti-siphon pipeline is set up to keep the pressure of the mother pipe at a positive pressure of 14KP to prevent siphoning.
How many ways does the 24.660WM Dongfang unit generator seal oil source have?
Answer: The main oil source of the generator seal oil is the oil supply of the sealed oil pump, and the first backup oil source (that is, the main backup oil source) is the main oil pump of the steam engine. When the main oil source fails, the first standby oil source is automatically put into operation. The second standby oil source is supplied by the standby AC electric seal oil pump on the main oil tank, and when the speed of the steam turbine is less than 2/3 of the rated speed or the first standby oil source fails, the second standby oil source is automatically put in. The third backup oil source is provided by the DC sealed oil pump.
25. What is the purpose of oxygenating water?
A: The core of the oxygenation process is that oxygen has a passivation effect on metals under the condition of high water purity. By changing the feed water treatment mode, the iron content of the boiler feed water is reduced and the flow accelerated corrosion of the furnace front system, especially the inlet pipe of the boiler economizer and the high-pressure heater tube, is inhibited, so as to reduce the deposition rate of iron oxide in the boiler water wall tube and prolong the chemical cleaning cycle of the boiler. This inhibits the formation of oxide scale.
26. How to arrange the extraction system of our factory?
Answer: The unit adopts nine-stage non-adjusted steam extraction (including high-pressure cylinder exhaust). The first, second and third stages are supplied to three high-pressure heaters, of which the third-stage steam is supplied to the No. 3 high-pressure heater after heat exchange by an external steam cooler; the fourth-stage steam is supplied to the deaerator, the boiler feed pump steam turbine and the auxiliary steam system; the fifth, sixth, seventh, eighth and ninth stages are supplied with steam for five low-pressure heaters.
27. During the start-up process, how is the inverted heating regulated?
Answer: When the unit is started in cold state, when the metal temperature of the inner wall of the high-pressure inner lower cylinder is less than 150°C after the adjustment stage, the steam turbine needs to pre-warm the high-pressure cylinder, and when the metal temperature of the inner wall of the high-pressure inner lower cylinder is greater than 150°C after the adjustment stage, the pre-heating of the high-pressure cylinder is over. Confirm the following items before preheating the high-pressure cylinder: 1) The steam engine crank has been put into operation normally. 2) The condenser pressure is not higher than 13.3kPa (vacuum is not less than -88kPa). 3) The metal temperature of the inner wall of the high-pressure cylinder after the adjustment stage is less than 150°C. 4) The main steam valve is in the closed state, the high discharge check valve is closed, and the electric valve of the first section is closed. 5) The pressure of the inverted warm steam is not less than 0.5MPa, and there is a superheat of more than 28°C.
28. Why is there a safety door at the outlet of the sealed oil pump?
Answer: The sealed oil pump is a screw pump, because the gap between the screw and the screw is very small, so the high-pressure liquid on the pressure side is very little through the leakage back to the suck side, in order to prevent the equipment from being damaged when the outlet door is closed or the liquid pipeline is blocked, a safety valve is set up on the outlet side of the pump, when the pressure exceeds the specified value, the safety valve is automatically opened, and the high-pressure liquid is discharged back to the vacuum box.
29.What is the function of the sealing oil system?
Answer: The function of the sealing oil system is to use the hydrogen in the oil sealing machine to prevent hydrogen leakage to the outside, and also to prevent the air outside the machine from entering the generator, and the sealing oil also has the lubrication and cooling effect on the sealing pad.
30. How to fix the condenser heat exchanger tube on the tube sheet?
Answer: The fixing methods of the condenser heat exchange tube on the tube sheet mainly include the pad installation method, the tube expansion method, and the welding method (titanium tube). In the gasket method, the two ends of the tube are placed on the tube sheet and then sealed with packing. The advantage is that when the temperature changes, the copper pipe can expand and contract freely, but after a long running time, the filling will rot and cause water leakage. The tube expansion method is to place the heat exchange tube on the tube sheet, and use a special tube expander to expand the heat exchange tube, and the outer diameter of the end of the heat exchange tube after the expansion is 1~1.5mm larger than the original, and it is in close contact with the tube sheet, and it is not easy to leak. This method is simple and rigorous, and is now widely used in condensers, mostly used in copper heat exchange pipes. The welding method is to weld and seal the nozzle and the tube sheet with an appropriate electrode or the same material after the heat exchange pipe is expanded by the pipe expander. This kind of sealing form has excellent sealing effect, and is not easy to produce leakage of the nozzle due to expansion, and is mostly used in stainless steel heat exchange pipes and titanium heat exchange pipes.
31. What is the role of SPE technology for solid particle erosion?
Answer: During the start-up process, the high-pressure nozzle (especially the regulating stage), the medium-pressure nozzle, the moving vane and the main steam valve and the bypass valve of the flow part of the steam turbine with supercritical pressure often suffer from solid particle erosion, which refers to the fact that when the steam temperature reaches more than 450 °C, the oxide scale layer ferric oxide or ferric tetroxide in the superheater and the main steam pipeline is different from the parent material and causes it to fall off, and these hard particles enter the steam turbine with the steam. Solid particle erosion leads to a decrease in throughflow efficiency, a decrease in power, a shortened maintenance cycle, and an increase in maintenance costs.
32. How is an ultra-supercritical unit defined?
Answer: The critical state parameter of water is 22.115MPa, 374.15 °C, when the parameters of water reach the critical point, the vaporization will be completed in an instant, that is, at the critical point, there is no longer a two-phase zone between saturated water and saturated steam, and there is no longer a difference between the two parameters. When the unit parameter is higher than this critical state parameter, it is usually called a supercritical parameter unit. In the mainland, the main steam pressure is greater than 25Mpa or the steam temperature is greater than 580 °C, and the unit is usually regarded as an ultra-supercritical parameter unit.
33. How is the water supply system of our factory arranged?
Answer: The feed pump of our factory is equipped with a 2×50% capacity steam pump, and there is no electric pump. Equipped with 100% capacity steam pump, the single pump is in the 40~100% load range of the unit, the pump matches the load of the main engine, and the adjustment is more convenient. If the load is less than 40%, it will switch to the standby steam source, which can also ensure the normal operation of the unit. Although the 100% capacity pump is slightly less expensive than the 2×50% capacity pump scheme and has high operating economy, the unit can only be shut down or run at reduced load (equipped with a standby electric pump) when the 100% full-capacity steam feed pump unit fails, which affects the availability of the power plant. Equipped with 2×50% capacity steam pump, the advantage is that when a steam pump unit fails, it can still operate with 50% load.
34. Why is it stipulated that the pressure of the stator cooling water of the generator cannot be higher than the hydrogen pressure?
Answer: Because if the generator stator water pressure is higher than the hydrogen pressure, the stator will be grounded when the generator stator water leaks, which poses a threat to the generator. Therefore, the cooling water pressure of the generator stator should be kept below a certain value of hydrogen pressure. Generally, the differential pressure is maintained at 35KPa.
35.Why does the steam engine need to pass the speed of the monitoring boundary quickly when starting?
Answer: Because of the speed of the monitoring boundary, the unit will have a strong vibration, and the long-term vibration will cause major accidents such as dynamic and static friction of the unit, bearing damage, and even spindle bending, so the steam engine needs to quickly pass the speed of the monitoring when it is started.
36. What are the advantages and disadvantages of using hydrogen as the cooling medium for steam turbine generators?
Answer: Advantages: (1) The hydrogen density is small, which greatly reduces the friction loss of the generator fan and ventilation system, and improves the efficiency of the generator; (2) The hydrogen has a large heat transfer coefficient and strong thermal conductivity, which can increase the single capacity of the generator and reduce the volume of the generator; (3) The insulation performance of hydrogen is good, and the ionization phenomenon is weak, which can prolong the service life of the coil; (4) Because the hydrogen density is small, and the closed circulation system is adopted, the noise of the unit can be greatly reduced. Disadvantages: (1) hydrogen is a flammable and explosive gas, as long as the air contains 5-76% hydrogen (volume ratio), it will explode in case of fire; (2) hydrogen is a lighter than air and very permeable gas, so the tightness of the generator is very high to prevent hydrogen leakage; (3) there must be a set of hydrogen production device to meet the needs of continuous hydrogen replenishment; (4) when the generator is filled with hydrogen and discharged, it is very cumbersome, the process is also very slow, and the technical requirements are very strict.
37. What is the effect of high addition and de-column on the hydrodynamics of the DC boiler?
Answer: Because the inlet temperature of the water wall decreases a lot after the high addition and decomposition, and the underenthalpy of the working fluid at the inlet of the water wall increases, it is easy to cause poor water circulation of the boiler and poor hydrodynamic stability, resulting in the deterioration of the heat transfer of the water wall and the increase of the temperature deviation of the outlet of the water wall.
What is the role of the oil turbo pump of the 38.660MW unit?
Answer: The oil turbo pump plays the role of an oil injector, which is a composite device composed of an oil turbine and a centrifugal booster pump. The high-pressure oil from the outlet of the main oil pump is supplied to the nozzle of the oil turbine through the throttle valve, and the high-speed oil flow behind the nozzle is turned and reduced in the moving blade channel, and the kinetic energy is converted into the mechanical energy of the impeller to drive the coaxial booster pump to rotate, and the oil of the main oil tank is pressurized by the booster pump and supplied to the inlet of the main oil pump through the filter screen. When the power oil work pressure is reduced, it is mixed with the make-up oil from the bypass valve to provide lubricating oil to the bearings and other equipment. The throttle valve mainly controls the driving power of the oil turbine, the opening increases, the driving power increases, the impeller speed increases, and the oil pressure at the outlet of the booster pump rises. The bypass valve and the relief valve are used to adjust the oil volume and oil pressure of the lubricating oil system, when the oil discharge of the oil turbine can not meet the flow required by the lubricating oil system, the oil is directly supplied to the system through the bypass valve, and the relief valve controls the final lubricating oil pressure. After the unit is rushed to 3000rpm for the first time, the above three valves must be adjusted to make the suction pressure of the main oil pump between 0.098~0.147 MPa, and ensure that the pressure at the bearing inlet pipe is 0.137~0.176 MPa, that is, to ensure that there is enough pressure oil to enter the oil turbine, so as to ensure the oil pressure required by the inlet of the main oil pump, and to ensure that there is enough oil to supply oil to the lubricating oil system.
39. What is the reason for the interruption of the cold water and how to deal with it?
Answer: Reasons: 1) Failure of the fixed cooling water pump. 2) The chilled water filter is blocked. 3) Improper system adjustment. 4) The water level of the fixed cold water tank is too low. 5) Leakage of fixed chilled water cooler. Treatment 1) Start the standby pump when the chilled water pump fails, if it is invalid, the inlet flow rate of the chilled water is as low as the action value, and the generator should trip. 2) If the constant cold water filter screen is blocked, it should be switched to a standby filter screen and the filter screen should be cleaned. 3) Check that the status of each valve of the refrigerated water system should be normal, and the water level, pressure and flow rate should be adjusted normally. 4) If the constant cold water pressure control valve automatically fails, it will be changed to manual adjustment. 5) When resuming operation after water cut-off, water should be slowly sent to the generator and exhausted. 6) If the cooler is leaking, switch the cooler,
40. What should I do if there is a negative expansion difference in the steam turbine during the warm and hot start-up process?
Answer: It is necessary to pay attention to the problem of negative expansion difference when starting in warm and hot states. Especially in the case of extremely hot start-up, the steam turbine is prone to negative expansion differences. If there is a negative expansion difference during the start-up process, try to increase the main and reheat steam temperature at the upper limit of the specified temperature rise rate, and properly control the load rise rate, and stop the load lifting or load reduction if necessary, so as to keep the expansion difference within the specified range.
41. What is the role of Dongfang Steam Turbine Seal Oil Recirculation Pump?
Answer: In normal operation, the lubricating oil is supplemented to the vacuum sealed oil tank, and a local oil circulation circuit is formed in the vacuum oil tank through the sealed oil circulation pump, so that the air and moisture in the oil are separated and discharged to the outside of the plant through the vacuum pump pipeline, so that the oil entering the sealing tile can be purified to prevent air and moisture from polluting the hydrogen in the generator.
