Abnormal operation of the Hydro Power Plant and its accident handling
(1) Reason
Under the condition that the head is unchanged, when the opening of the guide vane has reached the no-load opening, and the turbine has not reached the rated speed, or at the same output, the opening of the guide vane is greater than the original, the unit output is considered to be reduced. The main reasons for the decrease in output are: 1. Flow loss of the turbine; 2. Hydraulic loss of the turbine; 3. Mechanical loss of the turbine.
(Two) treatment
1. In the case of unit operation or shutdown, ensure that the submerged depth of the draft tube is not less than 300mm (except for impact turbines). 2. Pay attention to the water inflow and outflow conditions to keep the water flow balanced and smooth. 3. Keep the runner running in a normal state, and stop and check if noise is found. 4. For axial-flow fixed-paddle turbines, if the output of the unit suddenly drops and the vibration intensifies, it should be stopped immediately for inspection.
2. The temperature of the bearing bush of the unit rises sharply
(1) Reason
There are two types of bearings for Hydro Power Plants: guide bearings and thrust bearings. The conditions to ensure the normal operation of the bearings are correct installation, good lubrication and normal supply of cooling water. There are three lubrication methods: water lubrication, thin oil lubrication and dry lubrication. The reasons for the sharp rise in shaft temperature are: first, the poor quality of the bearing installation or bearing wear; second, the failure of the lubricating oil system; third, the mismatch of the lubricating oil label or the poor quality of the oil; fourth, the failure of the cooling water system; fifth, for some reason Vibrate the unit; Sixth, the bearing oil leaks and the oil level is too low.
(Two) treatment
1. Water lubricated bearings. Lubricated water should be strictly filtered to ensure water quality. The water must not contain a large amount of sediment and oil, which reduces wear on the bearings and aging of rubber.
2. Thin oil lubricated bearings generally adopt self-circulation, adopt oil-slip ring and thrust disc, which is rotated by the unit and supplies oil by self-circulation. Pay close attention to the working condition of the oil rejection ring. The oil rejection ring is not allowed to be stuck. The oil supply to the thrust plate and the oil level of the post tank.
3. Dry oil lubricated bearings, pay attention to whether the specifications of the dry oil are consistent with the oil used in the bearing, whether the oil quality is good, and lubricate regularly to ensure that the bearing gap is 1/3 ~ 2/5.
4. The sealing device of the bearing and cooling water pipe is intact to prevent pressure water and dust from entering the bearing and destroying the normal lubrication of the bearing.
5. The installation clearance of the lubricating bearing is related to the unit pressure of the bearing bush, the linear velocity of rotation, the lubrication method, the viscosity of the oil, the processing of parts, the installation accuracy and the Baidu of the unit vibration.
