Reasons for and nature of weld joints failure in hot reheat steam lines of 800-MW power units

The nature of and reasons for weld joint failure in the hot reheat (HRH) steam lines of an 800-MW power unit are analyzed. It is shown that the weld joint destruction happened in the softened area and is typical for the weld joints operating for a long time under creep conditions. Numerical simulation demonstrated that the weld joint exhausted its lifetime due to the impact of equivalent stresses that exceeded design values, this being the reason for the failure.     

Calculated analysis of the stressed and strain state of pipeline sector elbows

The stressed and strain state of sector-type pipeline elbows is analyzed using the finite element method. Features in which sector elbows of pipelines differ from circular elbows are revealed. Formulas for determining the maximal equivalent stresses in sector elbows are presented.     

Modification of technological control units for superheated steam temperature at 210-MW power units of the Primor’ye Power Plant

The results of analysis of operation of the temperature control system for superheated steam at the BKZ-670-140F boilers of the Primor’ye Power Plant (GRES) are presented. The possibility of updating of the injection system to improve the reliability and economic efficiency of power units of electric power plants is considered.     

Simulating the rolling of tubes and its effect on the stressed and strain state of the tube sheets used in the heat-transfer apparatuses of steam turbine units

A comprehensive calculated and experimental investigation of the stresses occurring in the tube sheet of a shell-and-tube heat-transfer apparatus under the effect of tube rolling forces was carried out, the results of which were used to estimate the stressed and strain state of a tube bundle caused by technological loads, and it is shown that these loads need to be taken into account for carrying out a refined strength calculation.     

Specific features of the schematic solutions adopted in the steam turbine units produced by the Ural Turbine Works and used as part of combined-cycle plants

Specific features of the schematic solutions adopted in the steam turbine units designed and produced by the Ural Turbine Works for use as part of combined-cycle plants are considered.     

The influence of external bending moments on the lifetime of bends in hot reheat pipelines

The influence of various factors (the initial pipe cross section ovality and external bending moments) on the lifetime of bends used in high-temperature pipelines is estimated using the techniques of continuum damage mechanics of metal. The investigation was carried out for two typical bends used in hot reheat pipelines. To this end, the bend lifetime was numerically analyzed taking into account the accumulated extent of damage based on the results of finite-element computations in geometrically nonlinear statement.     

Specific features of corrosion damage to heat-transfer tubes of steam generators used at nuclear power stations equipped with VVER-1000 reactors

Specific features of corrosion damage occurring to the heat-transfer tubes of steam generators used at nuclear power stations equipped with VVER-1000 reactors are considered. The results obtained from metallographic studies of flaws found in samples cut out from steam-generator tubes are analyzed. Regularities with which flaws of steam-generator tubes are distributed over the tube bundle volume are discussed. Approaches for assessing the technical state and remaining service life of steam-generator tubes are presented.     

Specific features of the connection of a reflectometer to power transmission lines for location probing

Methods for connecting a reflectometer to a 6–10-or 35-kV energized or deenergized power transmission line are considered. The effect of the parameters of connection filters, coupling capacitors, and choke filters on the parameters of probing pulses is considered. Recommendations regarding selection of the duration of pulses for probing of power transmission lines of distribution grids are made.     

Gland seal heaters and steam jet ejectors with surface coolers used in the steam units produced by the Ural Turbine Works

The designs of coolers for gland seal heaters, as well as the main ejectors and seal ejectors, used as part of cogeneration steam turbine-based steam turbine units developed by specialists of the Ural Turbine Works are described. The design features of the apparatuses connected with the specific features of their operation as part of combined-cycle plants equipped with cogeneration turbines are shown.     

Specific features of external heat and mass transfer in the vibration apparatuses used for regenerating spent fuel from nuclear power plants

We present experimental data on the coefficients of heat and mass transfer for freely floating bodies simulating fragments of cladding and large conglomerates of fuel, as well as on the local coefficients of heat and mass transfer over the bed height, which point to high intensity of heat and mass transfer processes that take place in the elements of vibration apparatuses intended for subjecting spent fuel from nuclear power plants to oxidative recrystallization.     

电力系统状态估计在抚顺电网中的应用与研究

介绍了地区电网状态估计的基本原理及功能，即利用实时量测系统的冗余度提高数据精度，从而自动排除错误信息，估计出系统的状态；在自满上采用基于等效电流量测变换的状态估计方法，使雅可比矩阵常数化，充分利用了系统量测类型多的特点，将量测支路电流作为已知量带入计算，使其肯的较好的数值稳定性和计算速度；分析了在实时不良数据冲击下，该算法的稳定性和收敛性；在抚顺电网实际运行中效果良好。     

Present state of the problem of managing the service life of steam generators used at nuclear power stations equipped with VVER reactors

Modern state of steam generators used at nuclear power stations equipped with VVER reactors, existing problems, and topical matters of managing their service life are considered.     

The influence of nondensables contained in geothermal steam on operation of the power units at the Mutnovsk geothermal power station

A procedure for sampling nondensables and the results of measuring their composition and concentration in the steam at the Mutnovsk geothermal power station (MGeoPS) during the initial stage of the operation of its power-generating units in 2002–2003 are described. The operation of a two-stage system for removing nondensables from the turbine condenser is analyzed. The effect of hydrogen sulfide on the ecological condition of atmospheric air in the production area of the MGeoES is estimated.     

Prospects for comprehensively optimizing the combustion of design Ekibastuz and off-design Kuznetsk coals in the P-57 boiler of a 500-MW power unit

Technical solutions aimed at organizing efficient combustion of design Ekibastuz and off-design Kuznetsk coals in the P-57 boiler of a 500-MW power unit are proposed.     

我国输电线路用绝缘子运行现状及展望

输电线路使用的绝缘子运行状况的好坏直接关系到电网的安全与否。本文简略阐述了输电线路用各类绝缘子的材料和结构，针对运行中出现的绝缘子劣化、老化、使用寿命、检测和机电破坏强度等问题进行了分析，并对绝缘子的防雷、防污及防冰闪特性对运行特性的影响进行了论述。     

Specific features and problems relating to the present stage of technology used to construct automated process control systems for thermal power stations

The main problems relating to technology for development of automated process control systems for power units at thermal power stations implemented on the basis of computerized automation suites with a network structure are analyzed. The results from studies carried out at the Ivanovo State Power Engineering University’s Department of Control Systems are generalized with the purpose of improving the technology of end-to end designing and developing the functional structure of automated process control systems for thermal power stations.     

Specific features relating to implementation of investment projects in the Russian power industry

The state of generating capacities installed at Russian power stations is analyzed. It is shown that a total of 49.5 GW of capacities that are now in operation must be decommissioned by the year 2020 according to a forecast calculation. A plan of stage-by-stage commissioning of new generating capacities is outlined. Results of the first experience gained from new construction of power facilities are presented, and problems relating to involvement of Russian and foreign investors are pointed out.     

Selecting the optimal operating conditions of the calorifer installed upstream of the regenerative air heater used in a 300-MW power unit

A procedure is developed using which it is possible to select the optimal operating conditions of the calorifer installed upstream of a regenerative air heater depending on the outdoor air temperature, number of power units that are in operation, and their power output, taking into account the requirements for the microclimate of production premises.     

电力系统分区和解耦状态估计研究综述

电力系统状态估计已经成为电网EMS/DMS监测与控制的核心功能之一。有效的状态估计方法可以提高状态估计的精度、提升计算效率及改善估计结果的数值稳定性。首先介绍了当前电网分区准则,分析了各类分区方法需要研究的核心问题,并对基于网络拓扑和地理位置、AMI、MAS的电力系统分区状态估计的优缺点进行评述。然后从提高区域内部输配电网计算速度角度,指出基于快速解耦和相序解耦方法是处理当前三相平衡与三相不平衡系统的状态估计的有效解决方案。最后总结了分区和解耦状态估计研究存在的问题,并对今后进一步的研究方向提出建议。     

Specific features of the application of frequency converters in power electric drives of circulation pumps

Specific features of the selection and use of high-voltage frequency converters for asynchronous electric drives of circulation pumps of atomic power plants are studied.