The oil system is divided into turbine oil and insulating oil systems. The part of the hydraulic turbine is the turbine oil, which mainly plays the role of lubricating the guide bearings.
The pneumatic system includes low pressure, medium pressure and high pressure systems. Low pressure is mainly used for unit braking, bleeding and pneumatic tools are mainly used to supplement air; hydraulic device.
The water system is mainly used for equipment cooling, and the water supply objects are various water chillers. Additionally, some seals also use water.
What are the reasons for the increase in oil leakage in the water guide of the hydraulic turbine?
Answer: A, B, D
< p>Hydraulic generators can be divided into cooling methods: ① Air cooling type.The heat generated inside the generator is cooled by circulating air. Generally, a closed type with automatic circulation is used. The cooled and heated air is then forced through a water-cooled air cooler to participate in repeated cycles. ②Internal cooling type. When the generator capacity is too large and air cooling cannot achieve the expected effect, internal cooling is used for the generator. When the stator and rotor are directly supplied with cooling water for cooling, it is called a fully water-cooled hydrogenerator. When the rotor excitation winding and the iron core are still cooled by air, it is called a semi-water internally cooled hydrogenerator.The conduction temperature downstream of the hydroelectric generator set
If there is a gap on the dynamic sealing surface, an impo oil flowrtant will escape. There are no sealing strips in these two. places, which increases the possibility of leakage. ③ There is a sealing strip on the upper oil basin cover and the upper oil basin cover of the water guide. It is the same as the sealing strip at the bottom. The sealing strip is pressed by the tightening force of the bolt. form a sealing surface. There are also possible leak points ④ At the labyrinth ring, the upper labyrinth ring is closed on the oil basin and the lower labyrinth ring is locked on the water guide tile by the pin labyrinth lock. two labyrinth rings should measure 1.8~2.2mm. When the unit is running, oil flows up the labyrinth ring to the oil return hole at the junction of the two labyrinth rings. Oil rising here returns to the oil pool through the hole if the hole is clogged. As a result, the flowreturn is not regular and the turbine oil will be discharged out of the water-oil guide basin. ⑤ At the two sealing strips between the tile frame and the guide tile, it can be seen from the structure and working principle of the simple tile that the large shaft will continue to rub and impact the tile surface when the unit rotates, and the impact force is transmitted to the tiling frame through the tiling lifting bolts, the fixed tiling frame is fixed to the upper cover. If the impact force is large, the tile bolts will loosen, causing a large gap to form between the tile frame and the tiles. , which will cause oil leakage from the water guide bearing. ⑥The joint between the tile frame and the big shaft. The sealing material between the big shaft and the tile frame is pressed by the bolts. Long-term operation will cause the sealing failure of the feother and will cause an oil leak. ⑦Other oil leakage points mainly include: the output of the temperature measuring resistor, the connection point of the oil-water signal device, the oil port of the cooler, etc. If oil is leaking from these parts, it is only a very small amount and is not the main point of oil leaking. When installing the water guide bearing, the treatment process of the sealing surface did not meet the manufacturer's requirements. There were too many burrs and the sealing surface was rough, and there were even large pits that could leak oil. Through the above analysis, the exterior of the water guide bearing was carefully inspected, but no obvious oil leak points were found. Problems inside the water guide bearing, such as whether the oil return hole is blocked, whether the sealing effect of the sealing strip. is good, etc.., can only be resolved after disassembly of the bearing. The internal structure cannot be inspected. 3 water Solve the problem of oil leakage in the guide bearing In order to accurately grasp the amount of oil leakage in the water guide basin, the oil level in the water guide basin has been measure. The measurement data are shown in Table 1: Table 1 Oil. level measurement data Table 2 Processed oil level measurement data 3. 1 First treatment plan As shown in the table above, the daily oil leakage volume gradually increases, so the unit must be treated immediately to prevent oil leakage. rainy season, and the unit was not allowed to shut down for a long time, so as not to affect power generation. For a simple temporary treatment, use a pneumatic wrench to tighten the tile lifting bolts symmetrically to reduce the gapbetween the tile frame. and tiles. After treatment, measure again. The data is shown in Table 2. It can be seen from Table 2 that the tightening of the lifting bolts has played a certain role, but a large amount of oil still escapes every day, which does not fundamentally solve the problem. oil leak problem. The cause still needs to be studied in more detail. 3.2 The second treatment plan is to shut down the unit, disassemble the water guide bearing and perform a full inspection. When checking the two joints between the tile frame and the tile, it was found that the sealing strip was hard. During installation, the sealing strip was coated with more sealant. The glue and the sealing strip were integrated into one and became a hard block. so that the sealing strip has no elastic recovery force. A space is formed between the tile frame and the tile, and a largequantity of turbine oil escapes. No anomalies were found in the other rooms. According to the traditional treatment method, the same sealing strip was replaced, coated with the same sealant and reinstalled. The oil level measurement data after reassembly is as shown in Table 3. Table 3 Oil level measurement data after reassembly Table 3 shows that after the unit is processed, the oil leakage The initial oil is significantly reduced, but after the unit has been running for a while, the oil leak shows an increasing trend and rises to the level of the first simple treatment (tighten the elevator). The amount of oil leakage behind the tile bolt) shows that replacing the sealing strip did not have a good effect. The initial effect of replacing the sealing strip is better. The reason for the analysis is mainly that the initial sealing strip is stillelastic and the impact of sealant curing at low temperatures is not obvious. As the operating time increases, the sealing strip hardens together. with the sealant, and the sealing strip completely loses its elasticity. The sealing effect is lost; the material selected for the sealing strip does not comply with standards. 3.3 The third treatment plan learned from the second treatment and replaced it with Aizhigao recovery elastic sealing strip for the second time. At the same time, the traditional process was changed and the sealing strip was directly reinstalled without applying sealant after treatment. , The oil level in the water guide oil basin remains unchanged, completely solving the problem of oil leakage in the water guide bearing. 4 Conclusion: Choose sealing strips of different materials according to local conditions. Different environmentsWork elements must use sealing strips of different materials. If the working environment is particularly harsh, low temperature and humid, sealing strips with high elastic recovery power should be used. Some traditional processes need to be modified appropriately. No sealing tape should be used on sealing strips. It can be used directly without glue, so that the equipment can better adapt to on-site conditions. The sealing strip of the water guide bearing of Unit 5 of Wanjiazhai Hydropower Station was treated in the same way. After replacement, units 5 and 6 have been operating for more than a year without oil leaks.
Francis turbine. water How to deal with oil leaks Can an expert help you?
Overload operation, cooling system failure, lubrication system failure, etc.
1. Overload operation: If the generator set is in an overload state for a long time, the guide wheel will be affected by excessive heat, causing the temperature to rise.
2. Cooling system failure: There is insufficient cooling water flow in the cooling system. Problems such as insufficient cooling, cooler blockage, or cooling water pump failure cause the temperature to rise of the guide wheel.
3. Lubrication system failure: The lubrication system fails, preventing complete lubrication of the guide wheel bearing, and the heat generated by friction causes the temperature to rise.
If there is a gap on the dynamic sealing surface, a large oil flow will escape. There are no sealing strips in these two places, which increases therisk of leakage. ③ There is a sealing strip on the upper oil basin cover and the upper oil basin cover of the water guide. It is the same as the sealing strip at the bottom. The sealing strip is pressed by the tightening force of the bolt. form a sealing surface. There are also possible leak points ④ At the labyrinth ring, the upper labyrinth ring is closed on the oil basin and the lower labyrinth ring is locked on the water guide tile by the pin labyrinth lock. two labyrinth rings should measure 1.8~2.2mm. When the unit is operating, oil rises in the labyrinth ring to the junction of the two labyrinth rings. There is an 8 here Date received: 2007-01-04 About the author: He Haiwei (1972-1), male. , engineer, engaged in upkeep and maintenance work of power plants. 58 Hydroelectric power plant Mechanical and electrical technologycudgel Volume 30 the oil that rises here returns to the oil basin through this hole. If the hole is clogged and the return flow is not smooth, the turbine oil will be thrown out of the hole. the water-conducting basin. ⑤ At the two sealing strips between the tile frame and the guide tile, it can be seen from the structure and working principle of the simple tile that the large shaft will continue to rub and impact the tile surface when the unit rotates, and the impact force is transmitted to the tiling frame through the tiling lifting bolts, the fixed tiling frame is fixed to the upper cover. If the impact force is large, the tile bolts will loosen, causing a large gap to form between the tile frame and the tiles. , which will cause oil leakage from the water guide bearing. ⑥The joint between the tile frame and the big shaft. The sealing material between the big shaft andthe tile frame is pressed by the bolts. Long-term operation will cause the felt seal to fail and result in oil leakage. ⑦Other oil leakage points mainly include: the output of the temperature measuring resistor, the connection point of the oil-water signal device, the oil port of the cooler, etc. If oil is leaking from these parts, it is only a very small amount and is not the main point of oil leaking. When installing the water guide bearing, the treatment process of the sealing surface did not meet the manufacturer's requirements. There were too many burrs and the sealing surface was rough, and there were even large pits that could leak oil. Through the above analysis, the exterior of the water guide bearing was carefully inspected, but no obvious oil leak points were found. Problems inside the bearingwater guide, such as whether the oil return hole is blocked, whether the sealing effect of the sealing strip. is good, etc., can only be solved after disassembly of the bearing. The internal structure cannot be inspected. 3. Solution to water guide bearing oil leakage problem. In order to accurately grasp the amount of oil leakage in the water guide oil basin, the oil level in the water guide oil basin was measured. The measurement data is as shown in. Table 1: Table 1 Oil level measurement data Table 2 Processed oil level measurement data 3.1 The first treatment plan It can be seen from the above table that the daily oil leakage volume gradually increases, l The unit must therefore be immediately treated to avoid oil. The season was rainy season at that time, and the unit was not allowed to stop for a long time so as not to affect the impact. A simpletemporary treatment was carried out for electricity production. Use a pneumatic wrench to symmetrically. Tighten the tile lifting bolts to reduce the gap between the tile frame and the tile. After treatment, the measurement was performed again. The data is shown in Table 2. It can be seen from Table 2 that the tightening of the lifting bolts has played a certain role, but a large amount of oil still escapes every day, which does not fundamentally solve the problem. oil leak problem. The cause still needs to be studied in more detail. 3.2 The second treatment plan is to shut down the unit and disassemble the water guide bearing.Perform a complete inspection. When checking the two joints between the tile frame and the tile, it was found that the sealing strip was hard. During installation, the sealing strip was coated with more sealant. The glue and sealing tape have beenintegrated into one and became a hard block. so that the sealing strip has no elastic recovery force. A gap is formed between the tile frame and the tile, and a large amount of turbine oil escapes. No anomalies were found in the other rooms. According to the traditional treatment method, the same sealing strip was replaced, coated with the same sealant and reinstalled. The oil level measurement data after reassembly is as shown in Table 3. Table 3 Oil level measurement data after reassembly Table 3 shows that after the unit is processed, the oil leakage The initial oil is significantly reduced, but after the unit has been running for a while, the oil leak shows an increasing trend and rises to the level of the first simple treatment (tighten the elevator). The amount of oil leaking behind the tile bolt shows that replacing the bande sealing did not have a good effect. The initial effect of replacing the sealing strip is better. The reason for the analysis is mainly that the initial sealing strip is still elastic, and the impact of sealant curing at low temperatures is not obvious. As the operating time increases, the sealing strip hardens together. with the sealant, and the sealing strip completely loses its elasticity. The sealing effect is lost; the material selected for the sealing strip does not comply with standards. 3.3 The third treatment plan learned from the second treatment and replaced it with Aizhigao recovery elastic sealing strip for the second time. At the same time, the traditional process was changed and the sealing strip was directly reinstalled without applying sealant after treatment. , The oil level in the water guide oil basin remains unchanged, completely solvingment the problem of oil leakage in the water guide bearing. 4 Conclusion: Choose sealing strips of different materials according to local conditions. Different working environments need to use sealing strips of different materials. If the working environment is particularly harsh, low temperature and humid, sealing strips with high elastic recovery power should be used. Some traditional processes need to be modified appropriately. No sealing tape should be used on sealing strips. It can be used directly without glue, so that the equipment can better adapt to on-site conditions. The sealing strip of the water guide bearing of Unit 5 of Wanjiazhai Hydropower Station was also treated in the same way. After their replacement, units 5 and 6 have been operating for over a year without any water leak problems.uile.