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1.
Conclusions  
1.  Operation of the structures of the Votkinsk hydrostation occurs under condition different from those proposed in the design: there is no backwater from the reservoir of the Lower Kama hydrostation, as a consequence of transformation of the Kama channel the lower pool levels are 1 m below the design levels.
2.  As the experience of operating the Votkinsk hydrostation with considerable daily variations of the load and, accordingly, with considerable fluctuations of the lower pool level shows, the unprotected stretches in the lower pool in the zone of variable levels are subjected to erosion. They have to be protected during operation. The earlier works on revetting the eroded stretches are performed, the smaller the expenditures they require.
3.  At hydrostations operating under conditions analogous to those of the Votkinsk hydrostation it is necessary to conduct hydraulic studies in the lower pool and to measure the flow velocities for the purpose of eliminating erosion as well as for the correct selection of the variant of revetting the downstream stretches.
4.  For further safe operation of the Votkinsk hydrostation it is necessary to carry out in 1996–1998 revetting of the downstream slope of earth dam No. 1 and works on preventing scour behind the toe wall of the apron of the hydrostation in accordance with the design of Lengidroproekt.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 33–36, February, 1997.  相似文献   

2.
Conclusions  
1.  The 40-year experience of operating the Volga hydrostation indicates that as experience was gained in operating the equipment and it was modernized and improved, the design hydropower indices composing the basis of the high cost effectiveness of the station gradually increased and at the current stage of operation exceeded their design values.
2.  The Volga hydrostation is successfully fulfilling the function of the central, main base of the Russian power grid.
3.  The design data of the hydropower indices were confirmed by the actual operating results, which indicates correctness of the method of calculating the main parameters of large hydropower plants.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 29–32, March, 1997.  相似文献   

3.
1.  The plant manufacturer's power and efficiency guarantees are fulfilled.
2.  The power performance curves obtained for the hydraulic unit at four heads make it possible to select the makeup of operating units that will deliver maximum economy with the load distributed between the units.
3.  In operating the hydraulic units, special attention should be given to adjustment of the combiner curves in connection with the fact that its mismatch downgrades not only the economy of the hydraulic-turbine operation, but also the vibrational state of the hydraulic unit.
4.  Measurements of the vibration levels of the hydraulic units under several heads made it possible to determine the boundary line with respect to power over the entire range of operating heads.
Translated from Gidrotechnicheskoe Stroitel'stvo, No. 4, pp. 26–30, April, 1991.  相似文献   

4.
1.  The relative method of measuring the flow rates of water through a turbine is realized by simple means and provides a sufficient accuracy for the needs of hydrostation operation.
2.  Further works of design organizations, operating services, and manufacturing plants is necessary for increasing the reliability of the entire flow-rate measuring system.
3.  The operating staffs of hydrostations need to be materially encouraged to use the discharge efficiently for producing electricity.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 28–31, September, 1989.  相似文献   

5.
Conclusions  
1.  The hydroabrasive resistance of structural steels does not provide the necessary reliability of turbines operating on sediment-transporting rivers.
2.  Case-hardening of structural steels and resistant protective coating are used for increasing the reliability and life of parts of the flow passage.
3.  During actual service the effectiveness of casehardening decreases by half compared with laboratory tests, which is explained by the insufficient thickness of the protective layer. It is not advisable to use this type of surface protection for turbines with a high intensity of hydroabrasive action, since it is impossible to restore the protective layer under hydrostation conditions.
4.  Two types of protective coatings have the highest priority: protective electrode hard surfacing on a cobalt base, for instance, TsN-2, which while providing a high wear resistance of the surface, E greater than 3, permits making a protective layer of the required thickness 3–5 mm and repairing the flow part of the turbine directly at the hydrostation; synthetic polyurethane-based compositions making it possible to completely cover the runners with a coating thickness of 1.5–2 mm. Destroyed polyurethane coatings can be restored directly at the hydrostation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 44–47, November, 1997.  相似文献   

6.
1.  The problem of the thermics of hydrostations has recently acquired an acute character from the viewpoint of the effect of the pools of hydrostations on the microclimate of the region and it is in need of a prompt solution, since it can become an obstacle for substantiating the construction of many highly efficient hydrostations in regions with a harsh climate.
2.  Thermal forecasts should be developed at an early stage of designing a hydrostation and should be taken into account when selecting the site of structures, capacity, and operating regime of the hydrostation.
3.  A thorough survey and study of operating hydro developments are needed for developing measures to improve the ecological situation and for using the on-site data when creating standard methodological documents for designing and forecasting.
4.  A purposeful scientific and technical program should be devoted to a study of the effect of the thermies of hydrostations on the environment, which unites the efforts of many organizations of the USSR Ministry of Power and Electrification, Academy of Sciences of the USSR, State Committee on Hydrometeorology and Environmental Monitoring, State Education Committee, etc., and which is presently being formed by VNIIG.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 13–15, March, 1990.  相似文献   

7.
1.  The interaction of surface and subsurface waters increasing streamflow regulation is not taken into account in the practice of designing hydrostations.
2.  The proposed method of taking it into account, realized in the form of a program of calculations with the use of computers, makes it possible to estimate the effect of the indicated factor on any planned hydropower facility.
3.  A preliminary evaluation of taking into account the effect of the interaction of surface and subsurface waters for the example of a hydrostation with a seasonal reservoir made it possible to estimate it with respect to an increase of firm capacity within 0.4–0.9% and with respect to an increase of useful storage of the reservoir within 3–6%. This refinement should be added to the margin of safety of the power indices of the planned hydrostation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 14–16, February, 1988.  相似文献   

8.
1.  Small hydrostations under high-mountain conditions should operate with trash racks, devices should be provided for their cleaning from trash and shuga, as well as shuga-deflectors into the diversion canal.
2.  To reduce abrasion of the turbine equipment, it is necessary to provide operation of the suspended-particle settling basins.
3.  Specifications on the assembly of bearings and movable couplings should be developed for conducting maintenance works.
4.  During restoration works the profile of the runner blades should be made strictly according to the template in conformity with the plant drawings.
5.  Extremely necessary is the equipping of hydrostation with means for monitoring the technial parameters (bearing temperature, water pressure in the passage, wobble of the shafting, etc.), observation of the changes in which will make it possible to carry out in good time preventive maintenance and to reduce the probability of occurrence of breakdown.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 43–45, March, 1990.  相似文献   

9.
1.  For underground machine halls with a large number of units the areas of the assembly floors should be 1.5–2 times greater than for outdoor hydrosation powerhouses. Zones of the MH adjacent to the vehicular tunnels cannot enter into these areas; these zones should be regarded only as loading areas.
2.  The technology of excavating the underground machine hall, including pits for the draft tubes, introduced at the Hoa-binh hydrostation can be recommended for excavating large chambers of considerable length.
3.  The use of the given technical solutions when constructing underground hydroelectric station and pumped-storage stations in combination with fulfillment of par. 1 of the “CONCLUSIONS” will make it possible to reduce considerably the total construction time of underground machine halls and to provide start-up of all units.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 29–39, January, 1996.  相似文献   

10.
1.  The actual state of the outlet works as a whole can be evaluated as positive.
2.  To provide complete readiness of the outlet works for service regimes and to keep them in good working order, it is necessary to seal the existing damages and subsequently to carry out annual scheduled preventive maintenance.
3.  Long service of the restored bottom revetment of the stilling basin is possible under conditions of a moderate regime of waste discharges with their uniform distribution over the basin width, shortening of their duration, and reduction of the number of outlets put into operation.
4.  The restored basin revetment is in need of careful observation of its condition and sealing.
5.  The use of outlets for reducing the rate of filling the reservoir and especially for providing navigation releases is not permissible. They should be used only if the discharge capacity of the hydrostation units is insufficient for preventing filling of the reservoir during the spring flood above the elevation of the NPL as well as for not exceeding the NPL during passage of the summer-fall freshets with the reservoir filled to the NPL.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 9–12, April, 1994.  相似文献   

11.
1.  During the first years of operation of the turbines of the Ust'-Ilim hydrostation (1974–1979) increased cavitation erosion of the runner blades were noted. Blades with a maximum deviation of the geometry from the design had maximum erosion. Correction of the blade profile with the use of a three-dimensional template markedly reduced the intensity of cavitation erosion.
2.  Tests established that the best operating regimes of the units of the Ust'-Ilim hydrostation with respect to cavitation conditions is the load range 195–215 mW, deviations from which lead to a pronounced increase of cavitation erosion.
3.  A change in the profile of the trailing edges of the runner blades practically completely eliminated cavitation erosion on the rear surface of the blades near the trailing edges.
4.  Tests with hard-facing of the damaged blades by various electrodes showed the possibility of a substantial increase of the cavitation resistance of the hard-faced coating and accordingly an increase of the overhaul period with the use of electrodes of type TsN-22. It is required to organize immediately the production of cavitation-resistant electrodes, which are acutely needed for restoring cavitation damages of turbine runners.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 40–42, February, 1988.  相似文献   

12.
Conclusions  
1.  The presence of a large volume of the sediment load when constructing hydrostation reservoir leads under operating conditions to a change in the parameters and operating indices of the hydrostations in time, which should be evaluated as part of the designs being worked out.
2.  The cost effectiveness of investments in hydrostations depends on consideration of the change in their parameters and operating indices during siltation of the reservoirs. In this case the financial efficiency of investments depends on the indicated factors to a considerably less degree than budgetary efficiency.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 27–30, January, 1990.  相似文献   

13.
1.  The general vibration state of the control building of the hydrostation depends directly on the dynamic effect of the No. 1 unit. Vibration of the control building occurs in the zone of resonance with a frequency of 14.7 Hz, which corresponds to the blade frequency of the unit.
2.  The presence of an expansion joint between the block of the units and assembly area for all practical purposes does not prevent propagation of vibration and does not provide the principle of isolation of the block of units.
3.  One of the most effective methods of combatting resonance vibrations is to change the relationship between the natural frequency and frequency of disturbance by changing the rigidity of the structure.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 27–30, March, 1989.  相似文献   

14.
1.  The fluvial processes in the Ob River downstream of the hydro development, which markedly changed after damming the river and creation of the reservoir during the first decade of operation of the hydrostation, were expressed in the natural process of deep erosion of the channel, which had a diminishing character.
2.  Starting with the second half of the 1960s, quarrying in the Ob channel on the 30-km stretch of the lower pool adjacent to the hydrostation began to have a substantial effect on the natural process of transformation of the channel due to streamflow regulation and retention of sediments by the reservoir.
3.  During the period between 1966 and 1984 more than 40 million m3 of sand-gravel mixture was removed from the river channel and floodplain in the indicated stretch, as a result of which the decrease of levels relative to the normal, natural values at the site of the Novosibirsk gauging station was 0.9–1.0 m.
4.  A decrease of the levels downstream led to a deficit of water resources of the reservoir in dry years and, as a consequence, to worsening of the operating conditions of the majority of participants of the Novosibirsk water-management complex.
5.  After some stabilization of the position of the levels in the river in 1984–1986, the decrease, slump, of the levels in the stretch passing through the city subsequently resumed beginning in 1987–1988. The rating curve for the Novosibirsk gauging station in 1988 shifted downward from the analogous 1986 curve along the height axis by 15–20 cm.
6.  The priority task facing water users and consumers of Novosibirsk is the fastest possible realization of the recommendations of MGU, VNIIG, and ZapSibRNIGMI on partial restoration of the water levels in the stretch between the hydrostation and Novosibirsk city by constructing embankments damming nonnavigable branches and converting the Ob channel here at low-water discharges (less than 2000 cm3/sec) into a single-branch channel.
7.  For a radical solution of the problem of reliable provision of water consumers of Novosibirsk, it is necessary to reconstruct all intakes located downstream of the hydro development.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 25–28, October, 1989.  相似文献   

15.
1.  The construction of facilities of the southern Yakut hydropower complex, making it possible to bring 23–25 billion kWh of renewable energy resource into the energy balance of the Far Eastern power region, should become one of the strategic directions of power construction.
2.  For further elaboration of the concept of development of the energy base of the Far East, it is necessary in the shortest possible time to work out a Feasibility study of the southern Yakut hydropower complex, in which problems of the organization of construction and social and commercial substantiation should be elaborated; in the latter it is necessary to investigate all possible variants of obtaining such large investments in construction.
3.  The creation of the SYaHPC in the territory of the Yakut ASSR will have great significance for the development of the economy and improvement of the living conditions of the population of the republic. Export of part of the electricity to China will make it possible to reliably and constantly meet (as compensation for the removal of lands) a considerable part of the republic's needs for vegetables and fruits and other goods; it will make it possible to eliminate investing a part of the means and material and labor resources in unproductive and unprofitable agricultural enterprises.
4.  The SYaHPC with partial export of the electricity being generated at its hydrostation, being practically unaffected by inflationary processes by virtue of low operating expenses, under market economy conditions in the future can become one of the most profitable enterprises, a most important object of international and regional economic collaboration in the RSFSR.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 52–56, February, 1991.  相似文献   

16.
Conclusions  
1.  The off-design operating regime of the Chirkey hydrostation with difficulties in producing electricity and with long periods of high upper pool levels under conditions of seismic activity negatively affects the reliability of the surrounding rock mass and should be brought into correspondence with the design.
2.  Long and nonuniform operation of the Chirkey hydrostation outlet in 1997 showed sufficient reliability and efficiency of the structures, but activated negative processes in the surrounding rocks masses. The rupture of two rock bolts supporting the unstable mass on the left bank and increase of the rate of settlement of the left wall of the canyon are a warning signal. This requires a thorough examination of all support members and development of outlet operating rules.
3.  The consequences of the operation of the outlet for the reliability and stress-strain state of the dam sould be specially and comprehensively studied and analyzed. It is urgently required to determine the forces in the rock bolts supporting the unstable mass, to determine the magnitude and places of maximum stresses in the dam, and to monitor the rate of movement of the left-bank slope.
4.  It is urgently necessary to organize appropriate seismometric monitoring on the dam and to obtain daily (weekly) bulletins of the Dubka seismic station and periodic reports of the OMP DNTs on the seismological situation in the region.
5.  Before organizing seismometric monitoring on the dam or geodynamic test area of the Center of the Geodynamic Observation Service in the Electric Power Industry, it is necessary to use the earthquake prediction method of the Joint Institute of Physics of the Earth with the help of the dam's existing measuring systems. For this purpose it is advisable to automate the reversed plump lines by the “Sibgeoinform” or DIGéS (Diagnosis of Hydraulic, Power, and Other Essential Structures) method and to increase the accuracy and frequency of seepage observation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 6–10, July, 1998.  相似文献   

17.
1.  The arch dam of the Khudoni hydrostation can be constructed by the continuous conveyor technology as enlarged blocks.
2.  The rate of concreting the dam for the proposed dimensions of the blocks and times of covering them can reach 200–250 m3/h.
3.  To attain the indicated rate of concreting, it is necessary to construct near the dam site a new concrete plant with facilities for cooling or heating the concrete mix.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 13–14, August, 1990.  相似文献   

18.
1.  When ventilating complex underground hydraulic systems during their construction it is necessary to take into account the natural draft.
2.  The method presented for calculating the natural draft pressure drop of single tunnels (formulas 1–6) reflects the specific characteristics of hydrotechnical construction in mountainous areas and for the first time takes into account the direction of movement of the ventilation flow.
3.  For the particular conditions of constructing the Rogun hydrostation the values of the lapse rates were established, which can be used in calculations to take into account the natural draft when designing the ventilation of underground workings.
4.  For calculating the natural draft pressure drop of a complex network of underground workings, an algorithm was developed which makes it possible to calculate by a standard program on a computer the air distribution in the underground complex being constructed in relation to a number of technological and natural factors.
5.  On the basis of analyzing the results of different variants of the air distribution, the selection of the types and arrangement of the ejector fans (including in the future) was optimized, making it possible to increase the quality of ventilation and safety of underground operations, as well as to obtain a substantial technical-economic effect.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 26–29, August, 1988.  相似文献   

19.
1.  Forced ventilation accompanying the driving of underground workings leads to substantial temperature fluctuations of the roof surface and to the occurrence of thermal compressive stresses in the roof of the powerhouse. The maximum compressive stresses in the roof are observed at those times of the construction period when the values of the temperature gradients in the radial direction and values of the ratios of the height of the powerhouse to its width are maximum. This circumstance should be taken into account when designing and constructing underground powerhouses of hydrostations under conditions of the Far North.
2.  A tectonic fracture passing near the roof at the initial time of thawing of the mass promotes the occurrence of stress concentration in the roof, increasing the maximum compressive stresses by 3 times in comparison with the case when the rock is solid.
3.  The temperature regime of a perennially frozen rock mass around the powerhouse of a hydrostation during its operation stabilizes within 40–50 years of the constant thermal effect from the machine hall. In this case, a halo of thawed rocks forms. The temperature distribution in the rock mass after 15–20 years of operation of the hydrostation is close to steady.
4.  Thawing of frozen rocks in the operating period of the hydrostation, i.e., the establishment of a steady temperature distribution in the mass, is favorable from the viewpoint of the stress state of the powerhouse. In this case, thawing of the mass leads to a decrease of the values of the thermal stresses in the concrete roof of the powerhouse in comparison with the values of these stresses in the construction period occurring as a consequence of forced ventilation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 20–26, August, 1988.  相似文献   

20.
1.  In connection with the historically established economic conditions and existing agreements with neighboring countries, the cascade of Vakhsh hydrostation was designed on the basis of operating conditions in an irrigation regime and cannot provide Tajikistan's own need for power in the winter, the deficit of which is 4 billion kWh/yr. The traditional methods of solving this problem call for the construction of either an irrigation reregulator in the lower course of the river or a hydrostation operating in a power compensator regime in its upper course. Both these variants require vast expenditures of material and financial resources and provide an effect just due to one particular hydro development.
2.  The natural conditions of Tajikistan created the unique possibility of increasing the effectiveness of the combined operation of the Vakhsh cascade by constructing a tunnel conduit and using the runoff of the Pyandzh River in operating the Vakhsh hydrostations. With minimum construction costs the power effect of the cascade in this case increases substantially since it is achieved due to the repeated use of Pyandzh River water at all stations of the cascade and without any detriment for irrigation.
3.  Realization of the proposed project will increase the total power production of the cascade for all hydrostations specified by the scheme depending on the degree of streamflow regulation by the Pyandzh reservoir. The cost effectiveness of the proposed project is an order higher than that of the traditional variants. Even for the stations operating today on the cascade its effect is comparable to the effect of the Nurek hydrostation with respect to all indices. Here the total cost of the tunnel conduit together with the dam is an order lower than the cost of the Nurek hydro development.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 12, pp. 5–12, December, 1995.  相似文献   

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