CO2 power cycles are alternative to conventional steam power cycles. The power cycles with supercritical CO2 (sCO2) can be used in nuclear and also non-nuclear power industry. The advantage of sCO2 is more compact size of power cycle components – especially turbine and higher ...

Steam generators (SG) are one of the main components, which may represent certain limitations from the point of view of Dukovany NPP long term operation. The reason is the increasing trend of plugging of heat exchange tubes which has been observed in recent years concerned�...

In pressurized water reactors of nuclear power plants, unwanted hydrogen is generated by radiolysis of water and also by chemical processes in the primary medium. For safety reasons, this undesirable hydrogen must be removed from the primary circuit in a controlled manner. &...

Main coolant piping loop of WWER type of NPP DN 850 made of steel 10GN2MFA is manufactured with corrosion resistant cladding of internal surface. Loop has welded outlet nozzles of small sizes designed with internal inserted part made of stainless steel welded to main &#x...

Large number of recently developed NPP designs has implemented the In-Vessel Melt Retention (IVMR) strategy to manage hypothetical severe accidents. This strategy, more precisely denoted IVMR-ERVC (i.e. IVMR by External Reactor Vessel Cooling), is based on heat removal from the outer R...

LTOs Information System covers long term process of data collection, data processing and evaluation from diagnostic procedures, revisions and examination of power plant equipment in ČEZ a. s. The purpose of this report is to introduce new module, which covers mobile device &...

Thermal spraying is used as a technology ensuring the achievement of a local change in the properties in the area of the sprayed surface in relation to the intended purpose of using the component or sprayed surface. The paper deals with the qualification of thermal...

The aim of the cold sprayed sample evaluation was to test material properties required for an alternative design of deep storage nuclear waste container. The characterization of the sample was focused on verification of steel substrate chemical composition, measurement of copper ...

The new sonic coating systems are being developed in cooperation with IGS Europe. The application of these coatings is meant to serve as a repair to extend the operating lifetime of the heat exchangers and boiler walls in the incineration plants and other energy-producing faci...

There is presented in the paper: (i) why it is necessary to apply coatings in boilers, what protect, identification of wear, (ii) influence of fuel and combustion process, (iii) types of coatings, technology of application, service life and (iv) practical experience.

hermal spraying technologies make it possible to protect the surface of components against environmental influences and to renovate already worn surfaces. The potential of their use in the field of nuclear and conventional power plants was mapped within the solution of the N...

Bolts that compress together upper and lower parts of steam turbines are exposed to significant mechanical and thermal loadings. Their elongation due to creep deformation may lead to steam leakage in the turbine separating plane. In this paper, we present results of simulations&#x...

Cyclic fatigue of materials significantly affects the degradation and service life of powerproducing equipment. The present procedures of fatigue assessment provided in new international documents ISO and CEN are based on S-N curves of material properties and the Palmgren-Miner rule for...

The contribution provides an overview of four methodologies that are being developed in the framework of the National Centre for Energetics. The methodologies address the urgent need for optimising diagnostics and maintenance systems to achieve the level of availability required ...

For qualification of new and current methods of non-destructive testing, it is necessary to be able to produce test specimens with realistic flaws corresponding to flaws detected in the service of power industry devices. The Řež Research Center therefore develops suitable and effi...

The alternating current potential method (ACPD) is a suitable tool for measuring the depth of cracks in metallic materials. For its reliable use, it is necessary to design the arrangement of the measuring part well. Also the connection to the sample must be reliable.&#x...

The evaluation of the actual mechanical properties of the material is important especially for the correct estimation of the residual life of the component. In many cases, however, standard samples cannot be used due to the size requirements of the available experimental mat...

Last year, a paper was presented here, which dealt with the microstructure and properties of pipe with a wall thickness of 90 mm made of P92 steel, in which numerous dilutions were found, especially close to the inner surface of the pipe. The dilutions were pr...

Publications concerning precipitation changes and the associated changes in mechanical properties, such as impact work on refractory complex-alloyed austenitic steel SUPER 304H, are beginning to be found in the literature. This steel is used in Czech conditions on modernized thermal&...

A sponge-based Zr1%Nb cladding alloy (modified E110 alloy) is used as a fuel cladding material in the VVER-type reactors. Despite of sufficient creep data describing deformation processes in thermal creep of the alloy available in the open literature, we are still some distance fro...