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The evolution of the steam turbines in the last decades has led to the development of mobile low pressure blades, with large size and free standing technology, with superior performance in particular in the high stresses anchorage areas. The current market trend requires to manufacturers, that the control activities are carried out by minimizing downtime and by ensuring the proper functioning of the facilities. The need to ensure the structural integrity of the component, in this scenario, is satisfied with the development of a non-destructive "Phased Array" technique for finding operating defects in the dock, performed with and without the rotor in place the need for disassembly of the blades. In the present paper describes the stages of the project and the results obtained during inspection activities. [ABSTRACT FROM AUTHOR]

In this paper, we propose a J-groove dissimilar weld crack visualization system based on ultrasonic propagation imaging (UPI) technology. A full-scale control rod drive mechanism (CRDM) assembly specimen was fabricated to verify the proposed system. An ultrasonic sensor was contacted at one point of the inner surface of the reactor vessel head part of the CRDM assembly. Q-switched laser beams were scanned to generate ultrasonic waves around the weld bead. The localization and sizing of the crack were possible by ultrasonic wave propagation imaging. Furthermore, ultrasonic spectral imaging unveiled frequency components of damage-induced waves, while wavelet-transformed ultrasonic propagation imaging enhanced damage visibility by generating a wave propagation video focused on the frequency component of the damage-induced waves. Dual-directional anomalous wave propagation imaging with adjacent wave subtraction was also developed to enhance the crack visibility regardless of crack orientation and wave propagation direction. In conclusion, the full-scale specimen test demonstrated that the multiple damage visualization tools are very effective in the visualization of J-groove dissimilar weld cracks. [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]

This paper describes the new inspection methods of castings for oil and nuclear industry using phased array technique and dedicated probes. The phased array technique allows to considerably reduce the time of UT control thanks to a complete and exhaustive graphical representation of the analysis and thanks also to the use of a smaller number of transducers due to the versatility of the same. The time reduction joins a certain increase of the intrinsic quality of the PA technique, the ability to record the obtained results and the possibility of storage / display the performed exams. The PA technique is exactly at the halfway between the traditional ultrasonic inspection and the radiographic testing (often difficult to apply in service). It is possible to assume that, in the future, industrial radiography could be replaced by the phased array technique. [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]

This paper, starting with an introduction of passive and active thermography method, describes the possible control procedures and applications of this method in the oil industry. In particular, on the basis of in service experiences are described: predictive analysis (furnaces, boilers, fume pipes, chimneys, reactors, etc.) for the quantitative valuation of the insulating I refractory surfacing to recover during TA; coke search in ovens, with a focus on intervention procedures, monitoring of the thermal distribution (heat exchangers, air coolers or condensers) to verify the efficiency of the heat exchange; continuous monitoring of TIP temperature during transients (for example, during hydrogen plant start-up) in order to prevent critical events of such components; predictive analysis of electrical substations in order to monitoring thermal gradients, thermal map of the sliding contacts of turbine shafts to verify wear resistance, resulting in maintenance plan. [ABSTRACT FROM AUTHOR]

EST Plant (Eni Slurry Technology) consists of about 300 pressure vessels in the following principal units and section: * EST unit (unit 90); * Hydrogen production plant (Unit 95); * SWS sulphur recovery and tail gas treatment (Unit 92 and 94). More than 100 "critical" equipments exist in the EST complex, divided in units and sections on the basis of their type of service. In detail, the considered critical items include: carbon steel and low alloy steels heavy wall pressure vessels for high temperature, high-pressure hydrogen service; carbon steel pressure vessels in sour (wet H^S service) and amine service. For fabrication of such "critical" items special base materials and filler metals were adopted according to specific material requirement, special welding processes and fabrication sequences (including advanced automatic systems for non destrucutive testing) were used. This paper shows an overview on some critical aspects and experience of fabrication of main "critical" equipments of EST Plant. [ABSTRACT FROM AUTHOR]

In this paper the development of a welding procedure for the joining of steel type UNS S32760 (Super duplex F55) for use in the off-shore application is described. The joint was realized by means of the TIG (GTAW) manual process for the first passes and by a manual filling process with stick electrode (SMAW), in order to obtain the combination of mechanical and microstructural characteristics desired by the customer. The results obtained from the tests on the joints must provide proof of successful completion of all the tests to be part of the joint in accordance with the contractual requirements and stabilized the base for actual use in the production. The particularity of the case, in addition obviously to the inherent difficulties posed by the type of steel chosen, consisted in the request by the customer of a combination of mechanical and microstructural characteristics to the limit of the possibilities of a welding procedure suitable for use in production mode and times compatible with the internal market and production requirements. It was therefore necessary to design the welding procedure and choose the most suitable process parameters to achieve the required results. The evaluation of the joints to achieve in production and the characteristics to be obtained, has led to decide to perform welding with welding processes previously mentioned and in the welding position-frontal plane (PB/2G). The main problems to be considered in the design phase of the welding procedure, are to be found in the value of the maximum heat input, interval of interpass temperatures to be observed and the type of shielding gas to use with which material can be welded to avoid the formation of intermetallic microstructure phases of the joint and sappers of corrosion resistance. [ABSTRACT FROM AUTHOR]

This paper describes recent developments in the welding of thermoplastics, including laser welding of microfluidic devices and friction stir welding of fibre-reinforced plastics. It also describes new developments in the assessment of welds in thermoplastics, including the long-term mechanical testing and phased array ultrasonic inspection of welded joints in polyethylene pipes. [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]

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]

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]