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Analysis of the Production Processes Influence on Rail Deformations
Skalník, Vít ; Podaný, Kamil (referee) ; Vaněk, Mojmír (advisor)
The aim of this work is to assess the possibilities of using numerical simulation tools in the process of laser welding of the guide rail of a car seat. In the diploma thesis, a description of the components and the problem, which consists in the deformation of the groove of the guide rail, was made. A description was made of the manufacturing operations that the components go through. The positives of selected welding methods were evaluated and the choice of those used in production was justified. A description of the issues of laser welding, deformation and the use of simulation tools was made. The influence of individual production operations was evaluated in terms of the size and nature of deformations. Using the Visual – Mesh, Visual – Weld and Visual – Assembly simulation tools, which are products of the French company ESI Group, the same state of the simulated and real process was achieved. Subsequently, a proposal for the elimination of deformations and its verification using a simulation tool could be approached. The use of a spacer wedge, which acts on the most deformed places of the groove, was proposed. By its application, the resulting deformations were eliminated or significantly reduced. In the last part of the work, a technical and economic evaluation was made, taking into account the current global crisis and the important role of the automotive industry.
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Welding of the sanitary gully
Skalník, Vít ; Vaněk, Mojmír (referee) ; Kubíček, Jaroslav (advisor)
The aim of this paper is to plan out and realize an optimalization for the welding process of parts of a sanitary gully. Problematics during the welding process of the aforementioned parts together with the usage of welding fixture were explained. On the basis of characteristic signs of welding, an application of other methods was evaluated and the optimal option for the welding process was chosen. During the selection process, hygienic regulations of a non-state funded organization EHEDG (European Hygienic Engineering and Design Group) were taken into account. Furthermore, suggestions for adjustments of the welding process of the forefront of the gully were analyzed. The next step was the realization of the chosen plan and its testing. Part of the process was the implementation of a technological procedure and execution of WPS (Welding Procedure Specification). The end of this paper considers the tecnological-economic contributions of the changed in the procedure.
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Influence of welding parameters on angular distortion of weld
Crla, Tobiáš ; Vaněk, Mojmír (referee) ; Daněk, Ladislav (advisor)
The aim of this thesis is to qualify influence of welding parameters on angular distortion of weld. This thesis is divided into two parts - theoretical part and experimental part. The theoretical part is focused on solving causes of origin of tension and distortion during welding and on analysis of these causes. After the mentioned analysis there are also described solutions, how to prevent the potential origin of distortion and tension or how to proceed when these two phenomenas happen after all. In another section of this thesis there is term mentioned - method of welding MIG/MAG, because welding method is also affecting the origin of distortion and tension. Since this thesis is focused on angular distortion, there are theoretically described processes of this distortion and some methods of its assessment. These assessments are implemented also into the experimental part. In this part is practically examined influence of welding parameters on the angular distortion of weld on simple weldments. The measured values were compared to calculated values because of accuracy of measurement and verification of these values.
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Destructive methods of control of welding joints
Kopecký, Lukáš ; Richter, Tomáš (referee) ; Vaněk, Mojmír (advisor)
Bachelor´s thesis, the form of a literature review, discusses destructive inspection of welded joints. Using literary study of the issue, there are presented actual methods of destructive testing. The main aim of research is focused on describing the basic principles of the various destructive tests, their procedures, preparation of test samples and subsequent evaluation and comparison tests.
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Influence of shape of the electrode to weld pool
Hrádek, Jan ; Vaněk, Mojmír (referee) ; Kubíček, Jaroslav (advisor)
The project is focused on welding of TIG method. In this method is used non-melting tungsten electrode, which can have different top angles. In different literature there are different opinions about how angle influence weld pool. It was sharpen six different angles of electrode with whom was done welds on carbon steel S235JR and on austenitic corrosion resistant steel x5CrNi1810. The evaluation was done with help of chart where on the axis x is angle of electrode and on axis y are depth and width weld in millimiters. The result of this project was the prove of opinion that with more sharper angle of electrode is depth of weld smaller and width bigger.
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Stick welding carbon and high-alloy steels
Hendrych, Marek ; Vaněk, Mojmír (referee) ; Kubíček, Jaroslav (advisor)
This thesis deals with analysis of manual metal arc welding method or method 111. In the research part of this thesis are discused principles of this method, welding power sources and additional welding material-coated elecrodes. Further the thesis is focused on the weldability of steels, especially carbon steels and austenitic stainless steels. In the experimental part was accomplished measurement of operational characteristics of coated electrods. Measurement was carried out on sample of cabon steel S235JR according to ČSN EN and austenitic stainless steel X5CrNi18-10 accordig to ČSN EN. The evaluation envolves a comparison of the results and their justifications.
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Loss of strength during welding aluminous alloys AW 6060
Sklenář, Martin ; Vaněk, Mojmír (referee) ; Sigmund, Marian (advisor)
The aim of the bachelor thesis is to qualify the welding procedure according to the standard ČSN EN ISO 15614-2. At the beginning of the work is introduced a company with which was this thesis made. This is followed by an assessment of the issue of aluminum. Furthermore, the mechanical properties of aluminum are discussed. Follows by part about welding specially about aluminium welding. In the practical part the samples were welded and subsequently evaluated, then the design and qualification of the welding process was made. In conclusion, the possibilities and results that have been achieved are summarized.
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Development of Models of Al Alloys Behaviour for Applications in Numerical Simulations of Welding and Heat Treatment
Vaněk, Mojmír ; Věchet, Stanislav (referee) ; Neumann, Heinz (referee) ; Daněk, Ladislav (advisor)
The thesis deals with methodology for computational approaches for numerical simulations of welding and heat treatment of aluminium alloys. The thesis describes improvement of the current methodology for metallurgical part of the numerical analysis of welding, which is important mainly for prediction of dimensions of the heat affected zone (and deformations). The improvement was carried out based on CHD diagram that describes precipitation and dissolution of phases during continuous heating. The thesis also describes carried material measurements (measurement of chemical composition, dilatometric tests, tensile tests of several conditions of materials at temperatures up to 500 °C and measurement of aging curves), which allowed to significantly refine analysis results for the alloys EN AW-5083 and EN AW-6082. Based on an evaluation of the measurements, several conclusions were made. They can be useful for creation of material databases of other aluminium alloys. The thesis also describes quantification of dependence between tensile strength and yield strength on the Vickers hardness for different conditions of EN AW-6082. There is also methodology for numerical simulation of the heat treatment process of heat treatable Al alloys in the dissertation. The methodology is completely new approach which has never been published so far. Application of this method is based on user changes of the material database in software Sysweld after relatively easy measurement of aging curves. Therefore, the methodology can be considered as promising for application in industrial practice.
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Influence of Chemical Composition on Weldability of Structural Steels
Kachlíř, Jaromír ; Daněk, Ladislav (referee) ; Vaněk, Mojmír (advisor)
This work deals with the influence of chemical composition to weldability of construction steel S355, S275 and S235. The introduction is about marking steel according to norms EN 10027 and CSN 42 0002. It also marginally deals with the problematic of carbon equivalents, temperature of preheat and generation of martenzit during welding. The second half contains the evaluation of the examined steel samples. I focus mostly on mechanical properties, chemical composition and other steel charasteristics. All the samples are compared both to the other steels in its group and amongst each other.
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Prediction of welding joint distortion by computer simulation.
Vaněk, Mojmír ; Slováček, Marek (referee) ; Daněk, Ladislav (advisor)
In this master’s thesis there are set down dependencies of distortion of T-joints on the size of heat input and welding speed. Dependencies were found for single- and double-fillet welds, for single- and multiple-pass welding. The computer simulations were carried out in programs Visual-Weld and SYSWELD. The size of the melted zones, stress fields, material structure and hardness of the weld specimens were specified. Simulation results were compared with experimentally detected values.
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