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The reliable operation of a process plant is critical to the safety, performance, and profitability of a business. Failure Mode and Effects Analysis (FMEA) is a process of reviewing systems, subsystems, and equipment that identify potential failure modes, their root causes, and consequences. FMEA is also a risk assessment tool that has been used successfully in a wide range of process industries as an integral part of reliability-centered maintenance, safety management, and continuous improvement. The method has indeed been criticized, especially in the area of system assessment, but engineers still predominantly use traditional, unmodified FMEA best practices. In this study, a new conceptual model is proposed to improve the traditional technique and make FMEA a more autonomous, data-driven, and accurate method. The conceptual model of improved FMEA uses ANFIS and FIS models in one automated process that aims to solve the defect handling process from failure detection to quantification of risk level and prioritization of dedicated mitigation action.

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Quality control of welded joint is an indispensable part of the welding production process. As part of spot resistance welding group, cross-wire welding process showed great application for welding of products for everyday usage. The non-contact quality control checking is fit for purpose due to specific characteristics of welded products that consist of two cross welded wires or a combination of wires and strips. This work proposes a new method for detecting and measuring of required dimensional parameters, but also founds its applicability for other products if required. A crucial parameter of this research is the height of welded joint, which is necessary for calculating the penetration of the wire into the wire. The proposed measuring method with a reconfigurable measuring system is explained in this paper. The main component of this system is using a machine vision system, which has become an indispensable part of industrial metrology and is considered one of the industry 4.0 concepts. The calibration process for such systems could be very complicated. This work shows an elaborated calibration procedure for this kind of measuring system with referenced standards made for this purpose. Measurement results are compared with ones obtained by conventional method. The focus of vision system is a substantial part as it dictates the quality of the system. This research is done within the project in collaboration with the industrial sector and all samples are from real processes. The results of measured penetration on one product group are showing the applicability of a reconfigurable measuring system in the welding sector, and demonstrate that measurement of welding penetration based on machine vision is feasible and can ensure accuracy.

To avoid the occurrence of surface cracks at the welds, it is important to lower the stress concentration in the zone of the weld face by an appropriate choice of parameters. A plethora of experiments was conducted varying four welding techniques. The welded samples were scanned with 3D scanners and the toe radius was measured on each sample. The significance of the obtained results was analyzed using Pareto diagrams. The experiment results analysis shows that the length of the electrode stick-out has a significant influence on the toe radius, while the shielding gas has a great effect on the toe radius. Moreover, with the analysis of results obtained by experiments it was proved that the interaction of the torch angle and the number of cover passes, as well as that of the torch angle and the shielding gas, has a significant influence on the toe radius.

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Welding is one of the most widely used metal joining techniques. However, improper technique and handling may lead to weld defects. Cracks that occur during the exploitation of the welded joints in places of increased stress concentration are called fatigue cracks. In our previous study, we suggested that lowering the stress concentration in the zone of the weld face may prevent surface cracks in butt-welded joints. Here, we further examined how welding heat input and external factors can be controlled to minimize the occurrence of fatigue cracks on welded joints. The fatigue cracks analyzed in this study occurred during the exploitation and are a consequence of the increased stress concentration at the toe of the weld. We performed twenty-four welding experiments comprising the following four welding conditions: torch angle, number of cover passes, length of electrode stick-out, and shielding gas (two environments were used). Stress concentration factors and heat input were determined via experimental data. The results suggested that higher heat input is associated with a lower risk of developing fatigue cracks. Thus, we concluded that fatigue cracks could be minimized by increasing the arc voltage and current while also reducing the welding speed.

The decision to introduce new process equipment is always a complex and risky process. An important competitive advantage in the automotive industry is the integration of new process equipment into the production system using different decision-making models composed of measurable key indicators, scientific methods and empirical values, study defines a multi-criteria model based on various scientific sources combined with extensive manufacturing experience, which is an important tool for making quality decisions when introducing new equipment or technology. The study considers five main areas of indicators and characteristics: internal, external, financial, knowledge level, and other important indicators. By applying the Delphi method, the importance of the indicators is defined by multidisciplinary experts and the order of each characteristic is determined, which is then prioritized using MCDM methods to select the final solution. The paper presents the model definition and a practical application of the model to the castings manufacturing in the automotive industry.