TY - JOUR A1 - Kanzler, D. A1 - Müller, Christina T1 - How much information do we need? A reflection of the correct use of real defects in POD-evaluations JF - AIP Conference Proceedings N2 - To evaluate the capability of a non destructive testing system the “truth” of the used defects is essential. But what exactly is the truth of a real defect? And how much information is usable for the study? This presentation gives an overview about an advanced use of multiple metallographic cuts for the POD evaluation. In the presentation an approach is shown where information of metallographic studies are reconstructed and weighted to gain the essential information about real defects and which information are important for the detection with radiographic testing equipment. Furthermore, different connection points are discussed were additional knowledge from simulation and artificial defects can be used to gain additional certainty for the result of the evaluation. The methodology is used for the evaluation for the digital radiographic testing system for the testing of electron-beam welds, which is one possible choice to seal the Finnish copper canisters for the final deposit of spent nuclear fuel. T2 - 42nd annual review of progress in quantitative nondestructive evaluation: Incorporating the 6th European-American Workshop on Reliability of NDE CY - Minneapolis, MN, USA DA - 25.07.2015 KW - NDT KW - POD KW - Radiography PY - 2016 DO - https://doi.org/10.1063/1.4940652 SN - 0094-243X VL - 1706 SP - 200008-1 EP - 200008-7 PB - AIP Publishing AN - OPUS4-37596 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Helmerich, Rosemarie T1 - Is data obtained through Non-destructive Testing reliable? N2 - Civil engineers, who are involved in nondestructive testing have to solve an essential task: the transfer of the results of NDT-research into practice. NDT in civil Engineering is a quite new discipline. The results must meet the needs of the infrastructure owners to convince them about the usefulness of NDT. The issue of reliability of the NDT-data was discussed. T2 - Reliability Workshop Polytechnical University HongKong CY - Hong Kong, China DA - 06.04.2016 KW - Civil infrastructure KW - Reliability KW - POD KW - NDT PY - 2016 AN - OPUS4-37545 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertovic, Marija T1 - The first insights into the human factors in the inspection of railway axles N2 - The field of human factors has been concerned with prevention of organisational accidents and the maintaining of the highest safety standards in organisations with high hazard potential since its beginnings. Whereas it is known that human error has contributed to some well-known accidents and events in various safety-critical applications, as well as in railway, and that human factors have an impact on how reliable our non-destructive inspections are, very little has been done so far to address human factors, especially in the railway sector. The first steps in addressing human factors in the inspection of railway axles has been carried out by analysing the results of manual ultrasonic inspection of the railway axles during requalification in the education centre of the German Society for Non-Destructive Testing (DGZfP). In addition to the inspection, 160 participants were asked to fill out a questionnaire with the aim of identifying potential factors influencing their performance. The results showed that no correlation between the possible influencing factors (i.e. experience, level of qualification, satisfaction with the conditions during the re-qualification as well as in the daily practice and mental workload) and the inspection results. The explanation for this result was found in the fact that questionnaires can be used only to identify indirectly influencing factors. The only way to identify directly influencing factors and establish cause-effect relationships is by experimental study. The limitation of this study was the inability to influence the participants in any way during the requalification examination. Another angle used to identify potential influencing factors was the use of human-oriented Failure Modes and Effects Analysis. Carried out together with 4 experts from the field practice, two lecturers and two scientists, this analysis provided with an extensive list of possible failures, their causes, consequences and possible barriers. The largest benefits for the reliability of manual ultrasonic railway axle inspections in the practice can be found in attending to the organisational aspects of the inspection (e.g. processes, procedures, communication, education, supervision etc.). T2 - ESIS TC24 workshop "Integrity of Railway Structures" CY - Leoben, Austria DA - 24.10.2016 KW - Human factors KW - Reliability KW - NDT KW - Railway axle PY - 2016 AN - OPUS4-38251 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Christina A1 - Pavlovic, Mato A1 - Bartsch, Ludwig A1 - Rosenthal, Martina A1 - Jaenisch, Gerd-Rüdiger A1 - Holstein, R. T1 - Analysis and synthesis of NDT reliability using the extended modular model N2 - The aim of all the effort devoted to NDE reliability is to evaluate the reliability accurately, reliably and efficiently, in accordance with the specific requirements of industrial application taking into account the very different nature of influencing factors. The set up of the Modular Reliability Model in 1997 was a big step forward in the understanding of influencing mechanisms in terms of the three different main elements, i.e. the intrinsic capability (IC), the application parameters (AP) and the human factors (HF). The intrinsic capability stands for the pure physical-technological process of the signal detection caused by the waves or the rays from a material defect in the presence of noise (caused by the material and the devices). This intrinsic capability is the upper bound of the possible reliability. Already when measuring this intrinsic capability for thick walled components the original one-parameter POD should be extended to a multi-parameter POD, where, in addition to the defect size, a number of additional physical parameters, such as the grain size distribution (or attenuation), defect depth, and angle or surface roughness, must be considered. For real life cycle assessments it is necessary to evaluate the signal response from real defects. The industrial application factors, e.g. coupling conditions, limited accessibility, heat and environmental vibrations, diminish the reliability. The amount of reduction can be determined quantitatively, if the underlying conditions are controlled. In case they are not controlled it is necessary to count for a (unknown) fluctuation in the reliability in the field anyway. The third group of important influencing factors are the human factors, which do not only cover the individual performance capability of the inspectors but also the design of the working place, the procedure, the teamwork quality, interaction with systems, the organization, and finally, the relationship between the companies involved in the inspection process and to which extend the responsible parties are aware of it. Both the internal and external organizational context, affect not only the HF but also the IC and AP. After having analysed the single factors separately it is necessary to look how everything is interconnected. When comparing an “ideal inspection” with a “real inspection” it is worthwhile to look at the existing practices, rules and standards. How do they really support reliable testing? With respect to the industrial end user, it needs to be shown how the level of reliability of NDE, influenced by the different factors and their interaction, has an impact on acceptance or rejection of safety critical parts. The approach of analysis and synthesis will be illustrated by examples of the reliability investigation of the inspection of copper canisters for nuclear fuel deposit in Sweden and Finland and German Railway inspections (hollow axle testing). T2 - 19th World Conference on Non-Destructive Testing CY - München, Germany DA - 13.06.2016 KW - NDT KW - Reliability KW - Modular model PY - 2016 AN - OPUS4-37602 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Selby, G. A1 - Dunlap, M. A1 - Müller, Christina T1 - Observations on implementation of the BAM holistic reliability model N2 - Achieving reliability in NDE for nuclear power plants is a complex challenge. As engineers we tend to focus on the equipment and the written procedures; they are easy for us to understand, measure and control. This focus addresses only one of the four aspects of the BAM holistic model, namely, Intrinsic Capability. Another of the model's modules, Application Parameters, also is engineering-oriented as examiners work to ensure that the equipment and procedure can be applied correctly in the actual examination environment as it is found in the field, though in addition to engineering it requires organizational foresight and commitment to understand and prepare for that specific environment well in advance. The Human Factors reliability module is harder for us to think about. The procedure developers think, "Of course all the examiners in the field will understand all aspects of my procedure and execute them correctly." Most of our bad experiences with reliability occur when this happy thought turns out to be untrue. And finally, perhaps the hardest reliability module to affect is Organizational Context. Getting all of the stakeholders -- the plant owner, the NDE company, the examiners, the regulators, the qualification body, the equipment suppliers -- to think about reliability in the same way, years in advance of the examination, to think about reliability at every step in the long process leading to the day of the examination itself, is a heavy lift indeed. T2 - 19th World Conference on Non-Destructive Testing CY - München, Germany DA - 13.06.2016 KW - NDT KW - Reliability KW - Modular model PY - 2016 AN - OPUS4-37603 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kanzler, Daniel A1 - Müller, Christina T1 - Evaluating RT systems with a new POD approach N2 - The usefulness and purpose of evaluating nondestructive testing (NDT) systems and their capabilities has changed in the last decade. The conventional method of simply applying a familiar statistical algorithm to say whether the system is usable for the tasks is history. Nowadays, multiple parameter methods which describe the probabilities of detection (POD) of different systems or real defects need new characteristics and a broader variety of statistical models to describe the true system behaviour. The appraisal of the NDT system involves diverse departments within a company (engineering, NDT-operators, and statisticians), but is, at the same time, more needed and requested than in the past. In this article, an approach is discussed in which professionals from different fields worked well together, accomplishing cost-intensive metallographic studies in correlation with well-understood physical behaviour of NDT-methods as well as deep-discussed mathematical methods to create a holistic evaluation of the technical reliability for a specific radiographic testing (RT) equipment. The first part of the publication will show the comparison between metallographic grinding and the RT indications. An essential innovation over past evaluation methods was the use of a multi-scale smoothing algorithm, which describes physical parameters, which were not used in evaluation like the POD in this way in the past. In the second part the statistical requirements for the POD take the focus. It can often be hard to make significant statements; especially in the case where only a small amount of data is available. The combination of data and the use of knowledge from simulations are essential. One possible solution will be shown for the RT evaluation. The methodology is used for evaluating the digital RT system for the inspection of electron-beam welds, which was method considered to seal the Finnish copper canisters for the final deposit of spent nuclear fuel. T2 - 19th World Conference on Non-Destructive Testing CY - München, Germany DA - 13.06.2016 KW - NDT KW - Reliability KW - POD KW - RT PY - 2016 AN - OPUS4-37607 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Trappe, Volker A1 - Hickmann, Stefan A1 - Müller, Alexander T1 - Infinite life of CFRP evaluated non-destructively with X-ray-refraction topography in-situ mechanical loading N2 - Carbon Fibre Reinforced Plastics (CFRP) are more and more used in modern civil aircrafts. These days the whole fuselage is made of this material (B787; A350). Due to strict certification standards the normal in-service loading gives a low stress level compared to the static and even the fatigue strength of the material. Hence CFRP are assumed to have an infinite life. To evaluate this assumption, fatigue tests on CFRP-specimens were performed up to 108 load cycles and the first inter-fibre failure was evaluated non-destructively by accompanying X-ray-refraction topography. A tensile testing machine was integrated in a small angle X-ray scattering (SAXS) setup. X-ray refraction topography was performed while the CFRP-samples were tensile loaded. This non-destructive technique enables the detection of micro-cracking and inter-fibre failure especially for CFRP. For Glass Fibre Reinforced Plastic (GFRP) X-ray refraction and in-situ loading has already been successfully used. The increase of inner surfaces due to inter fibre failure was measured as a function of the stress state. Fatigue tests were performed at and below the limit of inter-fibre failure strength. State of the art is to assume the failure of the samples under cyclic loading as the fatigue life. Accompanying non-destructive X-ray refraction measurements reflects the damage state and enables to trace its evolution even if the total failure of the specimens does not occur. This investigation technique is of high interest to give the engineer a design value of infinite life which is practically often reached due to knock down factors of certification standards. Finally the infinite life was found for cyclic fatigue loaded CFRP-samples even under high inter fibre transverse and shear loading investigated up to 108 load cycles. T2 - 19th World Conference on Non-Destructive Testing CY - Munich, Germany DA - 13.06.2016 KW - CFRP KW - NDT KW - Fatigue KW - Damage evolution PY - 2016 AN - OPUS4-37567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holstein, R. A1 - Müller, Christina T1 - Analyzing the reliability of non-destructive tests using the modular modell - a practical approach T2 - Proceedings of the 19th World Conference on Non-Destructive Testing N2 - Non-destructive testing is an important tool to guarantee the safety of railway traffic. The infrastructure with tracks, switches and sleepers is regularly tested, the locomotives and wagons with their wheels, bogies and axles as well. Many years of experience and some events lead in Germany to a good practice in testing the railway components. Now, European authorities are drafting a system of common requirements and standards for the European Railway Market. The German practice combines an intensive training of the NDT-personnel including sufficient time for practical exercises with organizational measures of the companies, responsible for rolling stock and infrastructure. Through the example of UT-testing of railway axles it will be shown, how training and organizational measures influence the reliability of such testing. T2 - 19th World Conference on Non-Destructive Testing CY - München, Germany DA - 13.06.2016 KW - NDT KW - Reliability KW - Modular model KW - Railway KW - Human factors PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-375712 UR - http://www.ndt.net/article/wcndt2016/papers/mo1d4.pdf SP - id 19519, 1 EP - 6 AN - OPUS4-37571 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kanzler, D. A1 - Müller, Christina T1 - Evaluating RT systems with a new POD approach T2 - Proceedings of the 19th World Conference on Non-Destructive Testing N2 - The usefulness and purpose of evaluating nondestructive testing (NDT) systems and their capabilities has changed in the last decade. The conventional method of simply applying a familiar statistical algorithm to say whether the system is usable for the tasks is history. Nowadays, multiple parameter methods which describe the probabilities of detection (POD) of different systems or real defects need new characteristics and a broader variety of statistical models to describe the true system behaviour. The appraisal of the NDT system involves diverse departments within a company (engineering, NDT-operators, and statisticians), but is, at the same time, more needed and requested than in the past. In this article, an approach is discussed in which professionals from different fields worked well together, accomplishing cost-intensive metallographic studies in correlation with well-understood physical behaviour of NDT-methods as well as deep-discussed mathematical methods to create a holistic evaluation of the technical reliability for a specific radiographic testing (RT) equipment. The first part of the publication will show the comparison between metallographic grinding and the RT indications. An essential innovation over past evaluation methods was the use of a multi-scale smoothing algorithm, which describes physical parameters, which were not used in evaluation like the POD in this way in the past. In the second part the statistical requirements for the POD take the focus. It can often be hard to make significant statements; especially in the case where only a small amount of data is available. The combination of data and the use of knowledge from simulations are essential. One possible solution will be shown for the RT evaluation. The methodology is used for evaluating the digital RT system for the inspection of electron-beam welds, which was method considered to seal the Finnish copper canisters for the final deposit of spent nuclear fuel. T2 - 19th World Conference on Non-Destructive Testing CY - München, Germany DA - 13.06.2016 KW - NDT KW - Reliability KW - POD KW - RT PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-375732 UR - http://www.ndt.net/article/wcndt2016/papers/we1d4.pdf SP - id 19535, 1 EP - 8 AN - OPUS4-37573 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - McGrath, B. A1 - Holstein, R. A1 - Bertovic, Marija T1 - How NDT companies can benefit from human factors knowledge T2 - Proceedings of the 19th World Conference on Non-Destructive Testing N2 - Ultrasonic phased array is, currently, the technology which is being applied as the solution to a lot of inspection problems. The perceived benefits are seen to be worth the outlay on equipment and specialised personnel. Yet, there is a source of knowledge, freely available, which can also deliver immediate benefits, through more reliable inspection results, and consequently increased client confidence, but which is largely ignored by the greater part of the NDT community. This talk will review the latest Human Factors knowledge and provide practical illustrations of how companies can use it to improve their competitive edge. T2 - 19th World Conference on Non-Destructive Testing CY - München, Germany DA - 13.06.2016 KW - NDT KW - Reliability KW - Human factors PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-375742 UR - http://www.ndt.net/article/wcndt2016/papers/tu4d3.pdf SP - id 19532, 1 EP - 8 AN - OPUS4-37574 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -