The article deals with the concept of monitoring based on nonparametric statistics. It is supposed the possible application to monitor the technological systems of nuclear power plants. Modern complex plants and technogenic objects are equipped with industrial monitoring systems. The evolution of such systems in natural form is the generation of alternative concepts, constructs, and items selection for efficiency during operation

Scanning contact potentiometry (SCP) is used for defects detection and for determine the coordinates of the defects localized in welded joints. Studied samples are welded by manual arc welding of two halves austenitic steel 321H (Chromium-Nickel-titanium stainless Steel) dimension of each 200×110×13.5 mm. Thereafter welding, seam width is about 12 mm. Subsequently welded sample is inspected using X-ray radiographic testing system. In order to compare techniques capabilities, plotted potentiograms and weld radiograph are compared. Experimental outcomes prove that defects can be detected by SCP technique. SCP results are complied with mathematical signal analysis of defects. This method may substitute some destructive or nondestructive methods.

This study presents the results of electrophysical non-destructive testing of collectors welded joints to the body of steam generators PGV 1000Mof the reactor WWER-1000. The studied steam generators located in the Resource Сenter of National Research Nuclear University MEPhI at the site of reactors construction factory “Atommash” in Volgodonskcity-Russia. The primary loop collector was welded to the body of steam generators PGV 1000Mand the technical condition of welded joints was investigated by electrophysical non-destructive testing (EPhT). In steam generatorsmay appear corrosion and cracks due to corrosive environment and effect of stresses however,EPhTcan detect early stages of cracks. The study highlights the theoretical part of electrophysical diagnostics and control method, using modern mathematical signals analysis, and issues related to the practical implementation of EPhT in the factory. The novel alternative method of non-destructive testing can be used in diagnostic oil and gas pipelines, elements of complex technical structures and industrial equipment. It can be used in many industries where it is necessary to process control of the entire structure or its individual parts under operating conditions. Based on control results, potentiograms were constructed for various structural levels of the diagnostic signal. The results of controlled welded joints in steam generators showed their satisfactory condition.

Abstract The paper presents the results of nondestructive testing of process equipment of nuclear power plants a welding unit for the collector of steam generators PGV 1000M, the hull penetration and surfacing of the process pipe performed in the factory. The purpose of the study was to justify the possible use of contact potential difference at the stage of technological assembly and control of welded joints of steam generators in the factory, as well as to determine the prospects for using this method in operating conditions of process equipment.

Conducted evaluation of technical state of welded joints, welding the collectors of the primary loop to the body of the sample of steam generator PGV 1000, located in Resource center National Research Nuclear University MEPhI at "AEM-Technologies" Atommash factory in Volgodonsk. The results of point-by-point scan shows that SLS 1000 µv and above, for almost all samples detected multiple superficial imperfections caused by the presence of certain rust spots and traces of a deep spot corrosion, and the presence of small nicks, scratches and other imperfections.

A method of prediction based on linear extrapolation with the use of the mathematical expectation of the rate of variation of the values of a controlled parameter as the slope of an extrapolating line is presented. A method constructed with the use of a correction of a linear function is considered. Correction is performed with the use in the method of least squares of variable weight coefficients that regulate the influence of the interpolation nodes on the final result as a function of the distance of these nodes from the current values of the argument of the extrapolating function.

The development of algorithms for the prediction of technological operating failure of nuclear power plant equipment based on stochastic extrapolation of the values of technical parameters is discussed. The algorithms are tested on real archived data on the operation of the oil circulation system of the main circulating pumps in a power generating unit at a nuclear power plant.

A method is proposed for stochastic estimation of the time the parameters of monitored engineering objects will be within a specified range of tolerances based on the theory of mass servicing. An example is given of the application of this method to monitoring the parameters of equipment at nuclear power plants.

Statistical methods for treating parameters are suggested based on using distribution mixtures with identification of multivariant objects subject to the dominant influence of random factors with a finite number of states.

(2007). Markovian model of the process of manual arc welding. Welding International: Vol. 21, No. 1, pp. 55-58.

Analysis is made of the experimental data available from the literature on the solubility of ice and water in various compressed gases in a wide range of temperature and pressure. A new formula is derived that relates the equilibrium concentration xeq of steam in moist gas at preassigned temperature and pressure to the constants of the equations of state for condensed water and to the virial coefficients. This formula enables one to directly calculate the solubility of steam in compressed gas without using the previously suggested solution of the set of equations. The derived formula makes it possible to describe the entire array of experimental data in the range of parameters from 200 to 400 K and from 0.1 to 10 MPa with an error equal to or less than the experimental error

A calculation procedure and results forsteam solubility in compressed gases and the thermodynamic properties of wet gases at elevated pressures using the Lennard-Jones potential and semi-empirical rules for combining potential parameters are presented.

The thermodynamic properties of wet carbon dioxide are calculated on the basis of the technique developed by the authors using both the Lennard-Jones potential (12-6) and the Kihara potential of spherical centers. The calculation results are compared with each other and with the experimental data available. It is shown that the proposed model is quite suitable for computing the thermodynamic properties of wet carbon dioxide. The data that are presented are necessary for computing the volume, enthalpy, entropy, the isobaric heat capacity of wet carbon dioxide, the mass moisture content and the absolute humidity.