[en] The technique for calculating the fuel component cost for electrical and thermal power generation depending on the number of spent fuel assemblies is described in brief. It permits to react flexibly on the fuel cycle changes

[en] The calculation-experimental method for seismic analysis of NPP electrotechnical equipment has been developed and tested. The tests have been carried out at vibroplatforms of 50 t load carrying capacity, with 1-50 Hz frequency range and maximum acceleration up to 15 m/s² which is equivalent to maximum calculated earthquake of the force 9 zone. In the course of investigating dynamic characteristics of typical equipment one succeeded in revealing bolted joint slackening which resulted in the maximum acceleration spread from 1.6 to 4.8 m/s². Determinaing maximum acceleration and resonance frequencies has shown that dynamic characteristics of the typical equipment can differ. These tests permit to increase seismic stability of the equipment and reveal separate structural defects as well as the defects connected with mounting and assembly

[en] The system of computer-aided design (SCAD), enabling to design NPP ventilation simultaneously with designing NPP buildings is described. SCAD is developed as man-machine system on the base of ES computer, usihg PL/1 OS ES algorithmic language and optimizing compiler. SCAD introduction will produce considerable economical and technical effect, reduce the development period and improve the design quality

[en] Experimental data characterizing transients occurring in the WWER-440 reactor following switching-off of all the six main circulation pumps are analyzed. The eXperiments are conducted during power unit operation at power close to the nominal one. Data are obtained on changes in the thermal power and coolant flow rate in the reactor as well as on changes in the pressure and temperature of the coolant in the primary and secondary circuits and coolant margins after switching the pumps off. Comparison of the experimental data with calculation shows that the calculated flow rate, as compared with the true one, is reduced during the entire transient. Maximum deviation of the calculation from the experiment is attained at the 20th second and makes up 25%. It means that the real processes in the WWER-440 reactors proceed easier than shown by the calculation. It is concluded that reliable core cooling during the entire transient is ensured by actuation of fast response emergency protection system of the reactor. In this case the minimum coolant margin takes place at the 2nd second and makes up 3.32. Sharp decrease in the power in this case does not result in additional depressurization of the fuet cans

[en] At the Leningrad NPP during the seren-year period four K-50a-65/3000 turbine and their foundation deformation measurements have been performed by means of a high accuracy geometric levelling. Determined are: settling values and values of residual deformations of the lower foundation plate, thermal deformations of the upper foundation structure under different turbine operation conditions, turbine shafting bearing shafting at the horizontal joint level; horizontal time required for shafting bearing stabilization upon shut-down and start-up of the turbine. Tne turbine foundation columns elongation has been determined with accuracy of 0.05-0.06 mm and 0.06-0.08 mm at the shut-down or operating turbine, respectively. For levelling a leveller has been applied, the accuracy of measurement of relative height of which is equal to 0.03 mm at the 6 m collimating ray length. The measurement accuracy is decreasing at the operating turbine up to 0.04-0.05 mm. As a result of measurements it has been revealed that relative bearing shifting occurs during the first 8-10 days after shut-down and 4-5 days after start-up and reach 2.5 and 2.0 mm, respectively. In addition, shafting bearing centers shifting has been determined at the operating and shut-down turbine. The conclusion is drawn that the number of problems of shafting bearing alignment of high power turbines arising during their mounting, operation and maintenance, one may succeed in solving by means of high accuracy geometric levelling

[en] For power unit operation control it is very important that their technical-economical performance should be determined at every moment. A simplified calculation method of ²³⁵U, ²³⁸U and ²³⁹Pu requirements in WWER-440 reactors using the BIPR programs is suggested. The calculation error is 4.53% at confidence level of 95%. The method can be used for the on-line control and operation planning of power units with WWER-440 reactors

[en] The air cooling system for recirculation water of the Bilibin NPP is described. The recirculation water supply system of each of the four NPP units employs air-radiator mechanical-draft Heller system cooling towers combined with surface turbine condensers. The system has been successfully operated during ten years

[en] Operation of the water clean-up system and block desalination installation used at NPPs with WWER-440 reactors are briefly reviewed. Data characterizing the state of water-chemical conditions of the secondary circuit and contamination of the heating surfaces of the steam generators are presented. The schematic of the feed water flows, condensates and desalinated water within the secondary circuit, diagram of changes in the iron content and pH parameter in the feed water are presented. Analysis of the data reveals that the deposits contain 81-88% of iron oxides. Besides, they include CuO(1.6-3.2%), CaO(0.3-2.1%), SiO₂(1.4-3.6%), NiO(0.1-0.9%) and Na₂O(1.9-4.3%). It is concluded that the final normalization of water-chemical conditions, in particula., with regard to the content of corrosion products in the feed water and decrease in the intensity of the deposit formation may be attained only at 100% elimination of the turbine condensate

[en] A method is described for certification of pressure- and temperature on-line measurement channels in the data-processing system of the Kola NPP. The method is based on the determination of the water- and water vapour tempeAatures according to the pressure under saturation regime. The pressure is measured using calibrated pressure gauges in the period of reactor warm-up by the afterheat as a result of the run of the man circulation pumps. To evaluate the actual coolant temperature, the pressure dependence of saturation temperature placed in the computer, memory is used. A high accuracy of determination of pressure and temperature in water and water vapour is attained to be +-0.24 kg-f/cm² and +-0.5 deg C, respectively

[en] Start-up and adjustment works related to the putting in operation of two K-220-44/3000 turbogenerators at the Rovensky NPP first unit with the WWER-440 reactor are described. The turbines operate with saturated steam at 44 kg/cm² 255 deg C and 0.995 dryness degree before check valves with intermediate separation and two-stage superheating of steam coming into the low pressure cylinder, upto 241 deg C temperature at 2.71 kgf/cm² pressure. As a result of start-up and adjustment works a reliable operation of the main and auxiliary equipment of turbine plants is ensured. The possibility of long-term turbine operation at normal power without limits is checked, measures to increase the reliability and effectiveness of the second circuit of the unit are suggested