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The worldwide accepted standard for ensuring weld quality is ISO 5817. This standard developed from an old German standard, DIN 8563, which was originally intended as a means for understanding between welders in a workshop and the inspectors performing optical and non-destructive control of the welded joint. The criteria and groups were predominantly established in consideration of the effort to produce or to inspect a weld. Neither static nor fatigue strength of the welded joint were considered. Since that time research has progressed so that service behaviour can be assessed based on knowledge of the existing weld imperfections. This paper includes tables which correlate the fatigue strength of a joint with the quality criteria and groups of ISO 5817. The correlation has been established using butt and fillet welded joints in 10 mm thick plates as an example. The German Welding Society (DVS) has updated its guidance on the application of ISO 5817. Fatigue strength is one consideration in this effort. A revised version of ISO 5817 is under development. The present paper supports these activities by describing the current state of the art in terms of the relationship between weld quality criteria and groups with fatigue strength. It provides a realistic basis on which to define consistent quality levels in relation to fatigue strength. Thus, an economic specification of quality levels is made possible. [ABSTRACT FROM AUTHOR]

In the welding field, hot cracks are considered one of the leading metallurgical defects. To assess the tendency to hot cracking of the base material or filler material may be appropriate to conduct a campaign of special tests. In this paper is proposed an overview on the available types of tests under the standard UNI EN ISO 17641: 2006 distinguishing between tests in terms of self-restraint conditions and externally loaded conditions. [ABSTRACT FROM AUTHOR]

In this paper are described the results of experimental tests performed by IIS PROGRESS Laboratory to evaluate shape and dimension of Hall sensor probes, lite accurate calibration of Hall probe, with square sensor and suitable surface, provides the possibility of a reliable control of components for which very low residual magnetism values are required. The application of ASME BPV Code, Article 7 Appendix, Section V, is a valuable reference for determining the accuracy and reliability of Hall sensors measurement, to achieve the control sensitivity required and to ensure the quality of the component inspected. [ABSTRACT FROM AUTHOR]

Performing an heat treatment may he necessary in order to satisfy the requirements that the final quality and the service conditions may impose to a welded component. The relevant technical and operational complexity often requires the application of codes and standards (European and International). In this respect, this paper is focused on AWS standard D10.10: "Recommended Practices for Local Heating of Welds in Piping and Tubing". This reference not only provides essential information related to the realization of localized heat treatment on pipes but is integrated with requirements included in other standards both European (e.g. the BS 2633) and International (e.g. ASME B31.1, B31.3). [ABSTRACT FROM AUTHOR]

The developments of steel structures aim at light and slender constructions. Therefore, high-strength steels with good welding characteristics and a high ductility, aside from higher strength, have been developed by the steel industry. With increasing strength of the steel, the loads which have to be transferred in the welded connections are also growing. In building constructions, fillet and partial penetration connections are commonly used. When using high-strength steels, it is very important to ensure strength, as well as sufficient ductility and toughness of these welded connections, in order to allow for the necessary redistribution of stresses and internal forces. The use of high-strength steels can bring significant savings in terms of material consumption, weight, transportation and fabrication costs. Beside the savings due to the reduced material consumption, advantages result from the smaller construction weight and a faster fabrication by reduction of the weld thickness. However, especially for high-strength steel grades S460 and S690, the benefit of saving of material cannot be used, due to the present restrictive design rules. Therefore, the aim of this research project, realized by four partners, was the development of appropriate and modern construction and design rules, as well as manufacturing principles, in order to achieve an economical use of high-strength fine grained steels. This paper presents the results of a research project, investigating the strength and ductility of fillet welded connections of high-strength steels S460 and S690, by means of experimental and numerical analyses. Experimental and numerical investigations of the load bearing capacity and safety against brittle fracture at lap joints with longitudinal fillet welds, cruciform joints with transverse fillet welds and butt joints with partial penetration double-V-groove welds of high-strength steels S460M/ML and S690Q/QL have been carried out. Numerical investigations in terms of welding simulation and measurements of residual stresses have been performed, in order to identify the local microstructure, hardness, residual stresses and strength in the weld profile. These results support the assessment of strength and ductility of welded connections. Based on the investigations, recommendations for the design of welded connections of high-strength steels, in terms of load bearing capacity and safety against brittle fracture, as well as manufacturing principles, were derived. The results of the research project thus contribute significantly to an optimized use of high-strength steel in welded constructions. [ABSTRACT FROM AUTHOR]

The automotive industry deals with different challenges and market requires. In order to be competitive and meet the quality requirements, in accordance with product standards and end-users, it is necessary a constant stimulus for processes development and optimization. This is valid when it is applied to the processes defined special by the standard UNI EN ISO 3834, such as welding, soldering, brazing or riveting. The present paper highlights the main steps of the development of robotic laser brazing system of BIW - Alfa Romeo Giulietta roof welded joints and of SPR technology (Self Piercing Riveting) for the front dome suspension joint of Maserati Quattroporte and Maserati Ghibli cars. [ABSTRACT FROM AUTHOR]

The paper aims at describing the approach and contents of the new edition of ISO 5817, the most important reference standard in the field of definition and evaluation of Quality Levels for imperfections in welded joints. This standard is analysed in comparison with the previous editions in order to outline the main differences and variations introduced so that users can be guided in its implementation. [ABSTRACT FROM AUTHOR]

In the construction of welded structures the research, evaluation and acceptability of imperfections in welded joints are fondamental aspects. In the field of metallic constructions, imperfections can be divided into two groups: linear and non-linear imperfections. Imperfection becomes a defect if it does not fall within the acceptance criteria defined by code or designer and from there derives several corrective actions, such as heat treatment, painting, repairing... The different international codes examined show some common points on implementation of non-destructive testing, but very different are their approaches to the acceptance criteria. A designer choice of a particular acceptance criteria can be summarized in a few key points: stress evaluation of the welded joints, in service conditions, mechanical properties of materials, inspection procedures. The purpose of this paper is a comparison of international standards (European, American and Russian Codes) for the acceptance of imperfections in welded joints. [ABSTRACT FROM AUTHOR]

Following the first part, which was about the ultimate resistance check of the welded connections, the present paper focuses on the fatigue design criteria. After an introduction about the general problem of the fatigue, the article presents the standard design criteria based on the simplified Wöhler curves and with respect to the load history and structural detailing available. The final part handles with the Hot Spot Method, increasingly used and well-linked to the FEM. [ABSTRACT FROM AUTHOR]

In recent years ultrasonic flaw detection in welded components has taken advantage from the developments in robotic, electronic and IT fields. New ultrasonic techniques, such as TOFD and Phased Array, have deserved an increasing interest in NDT market. Their main purpose is to increase the reliability and repeatability of the results through the registration of data, allowing the substitution of radiographic technique which has well-known problem of safety and is time-consuming for thicker components. These techniques, in front of undeniable advantages, are limited by technical constraints that have to be taken into account in order to detect and evaluate in a proper way the defects. This paper focuses on experience gained by IIS Service in this field, showing the advantages and limitations possibly arising from a not correct application of automatic ultrasonic techniques. [ABSTRACT FROM AUTHOR]

This paper offers information on the beginning of qualification/certification activities in Italy and data and indications on the experiences gained by Italian Institute of Welding (Certifying Body Accredited by Sincert, and then Accredia, and Notified CE, www.iis.it) and more recently by IIS CERT (Certifying Body Accredited by Accredia and Notified CE, www.iiscert.it), applying the standards EN 473, ISO 9712 and the directive 97/23/CE (PED) on qualification, certification and approval ofnon destructive testing personnel. Particularly information updated to 31 July 2012 are given and discussed on the activity of qualification/certification since January 2001 (starting year for the application of EN 473, second edition, and PED directive) with reference to the issued certifications and approvals and to their distribution in method and level. Furthermore, it is reported that at the beginning of 2011 IIS originated two branches, IIS CERT e IIS SERVICE, both totally owned and passed to the first one its activities of certification and approval. Instead IIS maintained the training, education and laboratory activities; all of them, together with research and development activities, will be transferred to a third IIS branch, IIS PROGRESS (www.iisprogress.it), which will officially start these activities at the beginning of 2013. [ABSTRACT FROM AUTHOR]

Digital Radiography: Characterization of CR (Compu-ted Radiography) Systems for industrial applications. This paper analyzes the main elements to be taken into account in order to characterize a CR (Computed Radiography) System for industrial application. Nowadays, users of CR can carry out the characterization following, as a support, the procedure considered by EN & ISO standards, that have been recently proposed. The aim of this work is to underline the logic and the importance of each step and not to quantify performances of different CR Systems: task of each user indeed is to characterize his own system, obviously sustained by the manufacturer, in order to satisfy needs and requirements of different applications which he wants to approve CR for. [ABSTRACT FROM AUTHOR]