The paper analysis was performed of the current state of affairs in the field of quality control of welded joints and the subsequent decision on troubleshooting products. A set of parameters ...determining the quality of the welded joint in the class diagram format has been determined. The set of parameters, including typical variables of technological requirements, is expanded by expert parameters that create the prerequisites for the formation of an adaptive quality diagnostic system. The concept of building an adaptive diagnostic system based on an intelligent module that implements the functions of decision-making support by a technologist, operator and controller of the production process is proposed. Possible knowledge representation models, as well as intelligent computing algorithms are identified. On the example of the technological process of robotic welding, a sketch of the system interface is shown. A preliminary forecast of the effects of using system is proposed.
Welding input parameters play a very significant role in determining the quality of a weld joint. The joint quality can be defined in terms of properties such as weld-bead geometry, mechanical ...properties, and distortion. Generally, all welding processes are used with the aim of obtaining a welded joint with the desired weld-bead parameters, excellent mechanical properties with minimum distortion.
Nowadays, application of design of experiment (DoE), evolutionary algorithms and computational network are widely used to develop a mathematical relationship between the welding process input parameters and the output variables of the weld joint in order to determine the welding input parameters that lead to the desired weld quality. A comprehensive literature review of the application of these methods in the area of welding has been introduced herein. This review was classified according to the output features of the weld, i.e. bead geometry and mechanical properties of the welds.
In this paper a case study is presented, based on certain exercises applied to different welders, to evaluate the influence of welder’s fatigue on the quality of welding. The performed test was aimed ...at evaluating the technical performance (the welding act) of subjects, as well as the accuracy of weld lines. Five modules of exercises were applied. The exercises of each module were various, they were of medium level, so that they were neither overburdened, nor unsolicited, because both situations could lead to accidents due to fatigue. A weld line was performed after each exercises’ module. The visual quality of welding was appreciated according to the EN ISO 17637:2011 standard.
In this paper, based on the gas-kinetic theory of plasma, a theoretical analysis of the possibility of forming a plasma state in melting channel as a result of the interaction of high-energy ...electrons of the electron beam with the atoms of the material, being processed in melting channel (in free state) is proposed. Also the assessment of a possible impact of this process on the quality of weld metal is given. It is shown that if we take the electron-beam welding of large thickness with formation of a knife-form melting zone, the occurring processes can develop both in the direction of self-organization (synergetic, evolution) and chaotically (it all depends on the set of after-effects, caused by them, and their duration), which is manifested either as autofocusing and melted depth increase (synergy, evolution) or as formation of defects in the center of the channel (in the central part of the weld) in the form of steam and gas cavities of quite considerable size.
In this paper a case study is presented, based on certain exercises applied to different welders, to evaluate the influence of welder’s fatigue on the quality of welding. The performed test was aimed ...at evaluating the technical performance (the welding act) of subjects, as well as the accuracy of weld lines. Five modules of exercises were applied. The exercises of each module were various, they were of medium level, so that they were neither overburdened, nor unsolicited, because both situations could lead to accidents due to fatigue. A weld line was performed after each exercises’ module. The visual quality of welding was appreciated according to the EN ISO 17637:2011 standard.
After the Hyogo-ken Nambu Earthquake, it is of overriding importance to investigate influences of welding conditions, especially heat input and inter-pass temperature, upon the quality and the ...execution efficiency of welding parts in structured steel buildings . In this paper, an experiment to quantify effects of these conditions was carried out, and a relationship between heat input and inter-pass temperature was defined. As a result, it was clarified that heat input is the only index to control the quality and the execution efficiency.
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