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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 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   

3.
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   

4.
Conclusions  
1.  The experience of design works on the hydropower equipment of a hydrostation as large of a large number of suppliers requires a technical coordinator of the works with strict obligations on coordinating the designs of equipment with this coordinator before sending to the customer.
2.  At the stage of preparing the tender documents for complete delivery of hydrostation equipment it is necessary to enlist a design organization for a general assessment of the layout of equipment given in the tender drawings, for preparing alternative variants of the layout, and simplifying the process of final coordination of changes in the contract specifications in the case of winning the tender.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 3, pp. 52–54, March, 1998.  相似文献   

5.
Conclusions  
1.  Construction and operation of the Sayano-Shushenskoe hydrostation has not introduced noticeable deviations into the terrestrial and aquatic ecosystems of the region with respect to the most important indices-climate and water quality.
2.  It is necessary to continue monitoring the aquatic and terrestrial ecosystems for accumulating a databank on the effect of the hydropower complex on the environment.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 19–22, September, 1998.  相似文献   

6.
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   

7.
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   

8.
Conclusions  
1.  During discharge of a flow from a cone valve at small heads E0/hv≤1.2, when the upper part of the jet falls on its lower part, the maximum velocities are observed in the center of the flow, and when E0/hv>1.2 their maximum values shift toward the side walls, which can lead to erosion of the banks in the lower pool of the structures.
2.  Experimental dependences were obtained for determining the conjugate depths in the lower pool beyond the cone valves with free discharge of the flow into the atmosphere.
3.  The proposed efficient structures for dissipating the excess energy of the flow beyond cone valves make it possible to distribute the unit discharges over the width of the lower pool and to avoid dangerous erosion of the bottom and banks of the river channel.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 7, pp. 28–30, 1997.  相似文献   

9.
1.  The development of an ATDS should be realized individually for each operating station with consideration of the design characteristics of the units and should be aimed at solving one of the most important problems of increasing the operating reliability of the main equipment and economy of operating the hydrostation.
2.  The deterministic approach to compiling technological diagnostic algorithms makes it possible to use the operating experience gained and to make the diagnosis on the basis of the actual technical state of the units of the hydrostation.
3.  The ATDSs should satisfy the requirements of prompt, integrated, automatic, and dynamic performance (possibility of the modular buildup of problems being solved as a result of developing new diagnostic means and methods).
4.  The proposed development of an ATDS at the unit level should be done with the possible prospects of inclusion in the PCS of the hydrostation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 43–48, October, 1990.  相似文献   

10.
Model studies of the hydraulic operating conditions of an eddy tunnel outlet with an inclined shaft showed that:
–  for regimes without delivery of air into the flow core with swirler parameterA=1.1 and with delivery of air for all values ofA, submergence of the outlet section of the conduit in the lower pool noticeably affects the size of the core and promotes the formation of a hydraulic jump zone along the tunnel;
–  insignificant (in value) submergences of the exit section of the tunnel have little effect on the discharge capacity of the outlet (their differences is Δ=1.4% forA=0.6, Δ=2.71% forA=1.1, and submergence even increases the discharge of the outlet Δ=0.8% forA=0.83).
–  delivery of air into the flow core has little effect on the discharge capacity of the structure, with the exception of the layout with a swirler withA=0.6 (Δ=4.31% forA=0.6, Δ=0.5%, and Δ=0.9% forA=1.1);
–  considerable vacuums are observed for regimes without air in the flow core, the absolute values of which with increase ofA drop intensely from Hfc=−4.5 m to Hfc=−0.3m;
–  delivery of air into the flow core markedly reduces the vacuums in it and their values are close to zero;
–  with increase of swirler parameterA the area occupied by the flow at the end of the tunnel decreases;
–  regimes without delivery of air into the flow core are the most favorable with respect to the conditions of the pressure distribution on the conduit walls;
–  submergence on the downstream side does not lead to an increase of pressure on the conduit walls if the vacuum in the flow core increases simultaneously with this.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 41–44, November, 1997.  相似文献   

11.
1.  To reduce the cost and construction time of hydro developments, it is necessary to introduce more widely continuous concreting technologies. Concreting of heavily reinforced and thin-walled structures and members is most effectively done with cast concrete mixes by means of modern concrete pumps.
2.  As a result of experimental investigations of pipeline delivery of mixes by BN-80-20 concrete pumps, the values of the specific resistances during pumping of various compositions of the mixes and the local resistances of quick-disconnecting pipe connections were determined; recommendations were developed for calculating the distance of pipeline transport of the mixes by the concrete pumps; the values of Kf, the volume filling of the transport cylinders of the concrete pump with the plasticized concrete mix, and Kd, the inertial component of the pressure during displacement of the mix, were refined.
3.  The two-year experience of using the means (conveyors, concrete pumps) of craneless technology of placing concrete for construction of the powerhouse of the Shul'binsk hydro development showed that even with the high price and underutilization of the potential possibilities of the equipment and mechanisms, a considerable savings was obtained due to shortening of the construction time and start-up of the first unit of the hydrostation ahead of schedule.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 38–43, October, 1990.  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 energy-storage hydroelectric station (ESHES) can provide a 1.5–2-fold increase in peak capacity with a simultaneous threefold decrease in daily fluctuations of the water level in the lower pool.
2.  A decrease in the length of the concrete structures located in the river channel (especially the length) of the powerhouse) reduces the consumption of concrete for the ESHES in comparison with the HES, which compensates for the cost of constructing the additional structures of the ESHES.
3.  Unlike the HES, the ESHES operates in a sharp-peak regime and also during passage of flood waters.
4.  Contrarotating pump-turbines are best suited for an ESHES because of various combinations of heads on its turbine and pump parts.
5.  With increase in the speed of multistage hydraulic machines their placement depth decreases and the cost of the powerhouse is reduced.
  相似文献   

14.
1.  Concrete mixed with ammonia water and cured under a negative temperature has at an early age a higher impermeability than ordinary concrete without additives.
2.  The presence of up to 60% ice in concrete cured under a negative temperature does not lessen the physical and mechanical properties in comparison with ordinary concrete. Partial ice formation (25–30% of the liquid phase) promotes a considerable increase in strength of concrete and its frost resistance.
  相似文献   

15.
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   

16.
Conclusions  
1.  The modernized generators have a new rated power of 90 MW/105 MVA, which is 9.1% higher than their original power without any restrictions, with sufficient heating and vibration margins.
2.  As the test data showed, the power of the generator modernized according to variant 1 can be increased to 100 MW (i. e., by 21% versus the original) and according to variant 2 up to 105 MW (i.e., by 27% versus the original).
3.  Modernization made it possible also by using new materials and technologies to increase the efficiency of the generators by 0.15% with modernization by variant 1 and by 0.33% with modernization by variant 2.
4.  With modernization by variant 2 (with replacement of the stator core) thanks to the use of modern cold-rolled steel the steel losses decreased by 100 kW and the excitation losses by 34 kW.
5.  Thanks to using nonmagnetic elements in the end zone of the stator the additional losses decreased by 26 kW.
6.  Modernization of ventilation made it possible to reduce the air flow rate from 84 to 74 m3/sec with unchanged heating of the generator components. In this case the ventilation losses for any of the variants of the generator decreased by 60–70 kW.
Tests of the generators permit concluding a high effectiveness of modernizing the generators at the Plavinas hydrostation and expediency of continuing modernization of the next generators by variant 2, i.e., with replacement of the stator core and winding. As a result of such modernization it is possible to considerably increase the power of the units to 105 MW/123.5 MVA, in which case the efficiency of the generator increases compared with the generator modernized by variant 1 by 0.18%; the exciting power decreases simultaneously. In the case of modernization with complete replacement of the stator we can confidently predict reliable operation of the machines for the next 40–50 years, i.e., as newly installed. Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 33–34, March, 1997.  相似文献   

17.
Conclusions  
1.  The plan of arrangement of the monitoring and measuring instruments on hydraulic structures of the Sayano-Shushenskoe hydrostation, developed on the basis of an approximate calculated prediction of the SSS of the dam — foundation system without consideration of the technology of constructing the dam and structural and tectonic features of the rock foundations did not meet the requirements of present-day monitoring and needed substantial expansion.
2.  The installation of additional measuring instruments was done with consideration of the real scheme of the static behavior of the dam and foundation and with consideration of the need to monitor the technological measures being taken to restore the solidity of the dam and foundation.
3.  Nontraditional approaches to problems of monitoring hydraulic structures, automation of on-site observations, and the development and introduction of information display programs made it possible to increase the reliability and promptness of monitoring and to monitor the state of the dam at a modern level.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 32–34, September, 1998.  相似文献   

18.
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   

19.
Conclusions  
1.  When searching for the optimal steel percent needed for providing the bearing capacity of a specimen, it is necessary to take into account the factor of reinforcement arrangement in the soil.
2.  It is seen from the dependences γcd*=f(ζ) obtained for specimens with various steel percent that with an increase of the factor of reinforcement arrangement in soil ζ the work conditions factor decreases, which makes it possible to introduce the given factor in formula (1) for determining γcd*.
3.  The lining of the model must be regarded as an element increasing the bearing capacity of the reinforced earth model.
4.  In the case of a discontinuous and continuous lining the bearing capacity of the models (with the same steel percent) is higher than that of models with a flexible lining.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 3, pp. 19–21, March, 1998  相似文献   

20.
Conclusions  
1.  The positive results of grouting cracks in concrete of the upstream face of the Sayano-Shushenskoe dam are not limited to suppression of seepage between elevations 344 and 359 m. Substantial compression of concrete of the first column and beyond the limits of this zone at higher and lower elevations was obtained without advance of the cracks into the depths of the dam during injection of the grout under high pressures, which also prevented seepage.
2.  It is necessary to consider well-founded the requirement of limiting additional opening of cracks during grouting to 1.5 mm.
3.  When making calculations for estimating the effect of grouting on the SSS of the dam, one should not proceed from the average pressure in the crack being grouted, since its value is difficult to establish. It can tentatively be considered a rigid inserts over the entire front of the crack with a thickness on the upstream face of 1.75–2 mm and converging to 0 in the zone of joint I–II.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 34–39, September, 1998.  相似文献   

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