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Kopriva R.,Technical Integrity | Petelova P.,Technical Integrity | Eliasova I.,Technical Integrity | Kytka M.,Technical Integrity | Culek M.,Technical Integrity
IOP Conference Series: Materials Science and Engineering | Year: 2017

Article describes two innovative testing methods - Small Punch Testing (SPT) and Automated Ball Indentation Test (ABIT) - which are based on the determination and evaluation of material properties from miniaturized testing specimens. These methods are very promising due to minimum material needed for testing and also in case of testing highly irradiated materials of components that are not included in standard surveillance programs. The test results were obtained for reactor pressure vessel (RPV) base material 15Ch2MFA in both states - initial unirradiated and irradiated. Subsequently results were compared with standard tensile tests to prove applicability of these testing methods for the evaluation of degradation of irradiated structural materials of nuclear power plants. © Published under licence by IOP Publishing Ltd.

The Czech Republic became a pilot country to carry out a shipment from the NRI to the Russian Federation by means of specially developed casks, which are compatible with both the technology of Russian-designed research reactors and the technology of the reprocessing plant/n the Russian Federation. The crane and lift fixtures are equipped with a digital dynamometer that is used to monitor the weight of the basket during reinstallation into the cask. It prevents the disruption of the central suspension/hanger. The VPVR/M cask underwent three demonstrations to verify that the design was acceptable technically for handling and loading spent fuel at the research reactor facilities and for receiving and unloading at the Mayak facilities in the Russian Federation. NRI is participating in shipments of SNF from other countries within the framework of the GTRI program.

Liu Q.,Defence Science and Technology Organisation, Australia | Janardhana M.,Technical Integrity | Hinton B.,Monash University | Brandt M.,RMIT University | And 2 more authors.
International Journal of Structural Integrity | Year: 2011

Purpose The purpose of this paper is to demonstrate the preliminary work on using laser cladding technology for the restoration of structural integrity. Design/methodology/approach The primary methodology used in this research is to develop a laser cladding-based metal deposition technique to articulate restoration of structural geometry affected by corrosion damages. Following from this method, it is planned to undertake further work to use the laser cladding process to restore geometry and the associated static/fatigue strength. Findings This work has found that it is possible to use laser cladding as a repair technology to improve structural integrity in aluminium alloy aircraft structures in terms of corrosion reduction and geometrical restoration. Initial results have indicated a reduction of static and fatigue resistance with respect to substrate. But more recent works (yet to be published) have revealed improved fatigue strength as measured in comparison to the substrate structural properties. Originality/value The research is based on an acceptable materials processing technique. © 2011 Emerald Group Publishing Limited. All rights reserved.

Dian J.,Charles University | Konecny M.,Charles University | Broncova G.,Institute of Chemical Technology Prague | Krondak M.,Institute of Chemical Technology Prague | And 2 more authors.
International Journal of Electrochemical Science | Year: 2013

Electrochemical functionalization of porous silicon surface with polypyrrole via cyclic voltammetry method is presented. Surface morphology and spatial distribution of elements in the porous silicon/polypyrrole layer were inspected using Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy, respectively. Changes of surface chemical composition during electrodeposition were determined by Fourier-transform infrared spectrometry. Porous silicon samples were subsequently tested for selectivity improvement of photoluminescence sensor response in chemical sensors of organic vapors. Combined effect of polarity and size of detected analytes played a decisive role in interaction of analyte with polypyrrole layer and determined modified sensor response of porous silicon/polypyrrole composite. © 2013 by ESG.

Sirnes H.,Technical Integrity | Gundlach T.,Statoil
NACE - International Corrosion Conference Series | Year: 2012

Experience with Black powder in pipelines on the Norwegian Continental Shelf (NCS) is limited to a few pipelines. The cleaning of one of the pipelines has recently started and the analysis of the dust is on-going. Pipeline cleaning or operational pigging is a part of the maintenance program. The business driver for cleaning the pipeline is to be able to perform an inline inspection and avoid under deposit corrosion in the pipeline. 1 First operational cleaning runs after pipeline commissioning gave slurry as the pigging product. Some years later the slurry changed to black powder and caused operational challenges. Due to the low radioactivity (LRA) and the composition of the dust some restrictions for the receiving facility were identified. Modifications at the receiving facilitys have been performed to be able to clean the pipeline in a safe manner. The main business driver for the modifications at the receiving facilities is to ensure an environmentally friendly and safe operation. The dust has not given any problems in daily operation. After the first incident with black powder the Gas Processing Plant installed filter modules to handle the dust in daily operation. Prior to the start of the pipeline cleaning activities, additional filter capacity has been installed in order to ensure a proper protection of the Gas Processing Plant. This paper describes some of the history for the pipeline, the cleaning history, challenges and limitations and the analysis of the dust compared to previous analysis. ©2012 by NACE International.

Kopriva R.,Technical Integrity | Falcnik M.,Technical Integrity | Eliasova I.,Technical Integrity | Siegl J.,Czech Technical University
Procedia Engineering | Year: 2015

In the terms of nuclear power plant operational life management, current trend of components lifetime extension requires precise and credible information of structural material degradation. Present-day standard conventional methods of mechanical testing are usually based on the use of large specimens and higher consumption of testing material, whose availability and volume is often limited. For determination of material properties, sampling of the necessary volume of material is in most cases connected with affecting the integrity or even destruction of the assessed component. Moreover, several components are not usually covered surveillance programs, e.g. reactor pressure vessel internals. Innovative testing methods of Small Punch Testing (SPT) and Automated Ball Indentation Test (ABIT) are based on the determination of material properties from miniaturized testing specimens and their semi-destructive approach is very promising for the possibility of present data base of irradiated materials testing results enlargement and enable the option of component in- situ testing (ABI testing). Presentation is focused on description of the process of employment of these techniques in the process of irradiated NPP materials testing and evaluation at the accredited hot cell testing laboratory of UJV Rez, Mechanical Testing Department. Comparison with testing results from conventional mechanical testing methods is also depicted. © 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license.

Ayling J.,Australian Aerospace Aus Aerospace | Bowler A.,RAAF Base Edinburgh | Brick G.,Technical Integrity | Ignjatovic M.,QinetiQ
Advanced Materials Research | Year: 2014

The AP-3C Orion aircraft is the oldest aircraft in the Royal Australian Air Force (RAAF) inventory. The planned fleet withdrawal has been extended far beyond the original design service objective. Continued safe and effective operation has required the development of a robust ageing aircraft management approach. A fundamental aspect was supplementing the structural certification basis with appropriate standards in the form of fatigue management requirements from Federal Aviation Regulations (FAR) 25.571 [1] and Federal Aviation Administration Advisory Circular (FAA AC) 120-93 [2]. To develop and underpin the ageing aircraft management plan and transition to the supplementary fatigue management standards, the RAAF collaborated with the Original Equipment Manufacturer, Lockheed Martin Aeronautics Company, the United States Navy (USN) and other operators to form the P-3C Service Life Assessment Program (SLAP). This program provided Full Scale Fatigue Test (FSFT) data, associated analyses and analysis tools to support management in accordance with FAR 25.571. An important element of the ageing aircraft management plan included the introduction of a rigorous Safety By Inspection (SBI) maintenance regime to assure structural airworthiness. FAA AC 120-93 requires assessment of structural repairs to determine revised fatigue management and inspection requirements. Often, this information is derived using tailored analysis tools and detailed models on a case-by-case basis. This approach is specialized, expensive and usually occurs after the repair has been designed and installed. To avoid these limitations, the AP- 3C Repair Assessment Manual (RAM) [3] was developed to provide the repair designer with a design handbook approach to fatigue analysis. In conjunction with some simple Finite Element (FE) models, the RAM supports complete repair analysis prior to an aircraft leaving the maintenance venue. This paper will present the history of the SBI program, the genesis of the RAM and actual examples of assessing structural repairs on the P-3 platform using the RAM. © (2014) Trans Tech Publications, Switzerland.

Ciaraldi S.,Technical Integrity
Proceedings of the 22nd Pipeline Pigging and Integrity Management Conference | Year: 2010

A presentation on risk-based inspection covers the purposes of risk analysis; risk definition for pipelines; probability of failure; pipeline corrosion threats; onshore oil and gas pipeline failure; pipeline integrity management; holistic vs. specific risk assessments; and specific risk ranking examples. This is an abstract of a paper presented at the Pipeline Pigging & Integrity Management Conference (Houston, TX 2/17-18/2010).

Pistora V.,Technical Integrity | Posta M.,Technical Integrity | Lauerova D.,Technical Integrity
Nuclear Engineering and Design | Year: 2014

Rector pressure vessel (RPV) is a key component of all PWR and VVER nuclear power plants (NPPs). Assuring its integrity is therefore of high importance. Due to high neutron fluence the RPV material is embrittled during NPP operation. The embrittled RPV may undergo severe loading during potential events of the type of pressurised thermal shock (PTS), possibly occurring in the NPP. The resistance of RPV against fast fracture has to be proven by comprehensive analyses. In most countries (with exception of the USA), proving RPV integrity is based on the deterministic PTS assessment. In the USA, the "screening criteria" for maximum allowable embrittlement of RPV material, which form part of the USA regulations, are based on the probabilistic PTS assessment. In other countries, probabilistic PTS assessment is performed only at research level or as supplementary to the deterministic PTS assessment for individual RPVs. In this paper, description of complete probabilistic PTS assessment for a VVER 1000 RPV is presented, in particular, both the methodology and the results are attached. The methodology corresponds to the Unified Procedure for Lifetime Assessment of Components and Piping in WWER NPPs, "VERLIFE", Version 2008. The main parameters entering the analysis, which are treated as statistical distributions, are as follows:initial value of material reference temperature T0,reference temperature shift ΔT0 due to neutron fluence,neutron fluence,size, shape, position and density of cracks in the RPV wall,fracture toughness of RPV material (Master Curve concept is used). The first step of the analysis consists in selection of sequences potentially leading to PTS, their grouping, establishing their frequencies, and selecting of representative scenarios within all groups. Modified PSA model is used for this purpose. The second step consists in thermal hydraulic analyses of the representative scenarios, with the goal to prepare input data for the structural analyses (pressure and temperature variations in the reactor downcomer). The third step consists in performing structural analyses, covering (deterministic) temperature and stress fields calculations for all representative scenarios, and finally, probabilistic fracture mechanics analyses. The results of the third step analyses are conditional probabilities of initiation of fast fracture for all selected representative scenarios. Combining them with frequencies of all groups, the final value of (unconditional) frequency of initiation of fast fracture of the RPV is established. In this paper, examples of both input data and the results are presented. © 2013 Elsevier B.V.

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