|
|
Locating welds defects on cranes.
Zíka, Luboš ; Hála, Michal (referee) ; Kubíček, Jaroslav (advisor)
The diploma thesis deals with the problematics of weld defects of cranes localisation and check. The aim is to analyse non-destructive methods, monitor the occurence of defects and their form and also to suggest the procedure of correction. The work is divided into a theoretical and practical part. In the theoretical part, there is an analysis of individual methods of non-destructive testing that are used for weld check on a particular girder. There is also an analysis of welding technologies used when making a crane girder. The practical part deals with evaluation of weld defects using two methods of non-destructive testing. Furthermore, statistics of defects is realised. In conclusion, the statistics outcome is resumed and evaluated.
|
|
|
Laser cutting with air pressure assistance
Kramoliš, Lukáš ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
This project, elaborated within the engineering studies (code of field of study: N2301), deal with air supported laser cutting and its practical usage in industry. The project is divided into theoretical and experimental sections, consisting of detailed description of several successive steps of the experiment. The theoretical section describes the principle and function of laser, individual types of lasers and their classification, laser beam properties, laser cutting, etc. The practical part is focused on finding of a set of optimal cutting parameters, assessment of results of air supported laser cutting in terms of quality and accuracy of cutting surface. This part is followed by comparison of cutting surfaces with a conventional technology of laser cutting that uses oxygen and nitrogen. Final part of the project evaluates applicability of this unconventional technology from the economic point of view.
|
|
|
Comparison of oxy and plasma cutting
Solař, Luboš ; Hála, Michal (referee) ; Daněk, Ladislav (advisor)
This diploma thesis is focused on comparison of plasma and oxygen - acetylene cutting. A literature review of this issue is included in the work. For technological - economic evaluation, there were proposed a sample part to assess how optimal the cutting process is. Observed resulst and there comparison are stated in conclusion.
|
|
|
Plasma cutting by TransCut 300.
Bergauer, Radek ; Hála, Michal (referee) ; Kubíček, Jaroslav (advisor)
The thermal parting by plasma is progressive technology of material cutting. There is a new method based on the plasma stabilization by the steam, beyond common systems with gas stabilization. The potentialities of cutting by steam stabilized plasma are tested and the results are compared with regular gas plasma in this diploma thesis.
|
|
|
Technical and economic solving of barking knives
Novotný, Petr ; Hála, Michal (referee) ; Kubíček, Jaroslav (advisor)
The target of the study is theoretical explaining the condition of creation of the soldered point with regard to basic and additional mat. Below, the detailed analysis of the existing technical problem and consecutive design of the solution method.Content of the study is also technological process of production of the barking knife and choice of the efficient producer.
|
|
| |
|
|
Measurement of cutting edge roughness in the process of laser metal cutting using the Yb-YAG laser
Maňas, Petr ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
The project elaborated in frame of bachelor´s degree program B-STG (“Mechanical Engineering Technology”, 2303R002), evaluates the roughness of samples of cutting edge laser cutting. Cutting performed the fiber Yb:YAG laser. The samples consisted of structural steel J235JR and DC01, stainless steel X5CrNi18-10 and aluminium alloys AIMg3. They were evaluated according to the ČSN EN ISO 9013 standard. The classification of samples into classes according to the standards of accuracy. The theoretical part is consists of a description of the methods of cutting, a basic principle of the laser and its types. It includes cutting parameters and their influence on the quality of subsequent defects. It is described roughness measurement and standard ČSN EN ISO 9013.
|
|
|
Comparison of hand and orbital welding by TIG method
Dušek, Vojtěch ; Hála, Michal (referee) ; Kubíček, Jaroslav (advisor)
DUŠEK VOJTĚCH: Comparison of hand and orbital welding by TIG method This bachelor thesis presents a comparison of manual and orbital TIG welding. It describes the advantages and disadvantages of manual and orbital TIG welding. Mechanical properties, surface structure and heat input on the weld samples were experimentally compared. Thesis also includes technical-economic comparison of these two methods of welding.
|
|
|
Evaluation of the fillet weld geometry on process parameters for laser welding of stainless steel
Polášek, Marek ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
The present thesis deals with welding of samples to examine the resulting geometry of the weld in dependence on process parameters of the laser. Welding was carried out without additional material using a fibre laser. The material used was stainless steel ČSN EN 17 241. The values of regression coefficients of the resulting graphs show that the changes in the weld geometry - width and depth - vary quite linearly depending on the welding performance. Especially the weld depth is a common requirement in technical practice; the measured results of the experiment can be used to set the process parameters to achieve the desired depth of weld. Some welds exhibit weld defects such as porosity caused by formation of the keyhole due to a large dynamics of the process. The technical-economic evaluation offers a price estimate for one meter of weld for each welding speed used.
|
|
|
Arc welding of stainless steels for demanding working conditions
Matějíček, Josef ; Hála, Michal (referee) ; Kubíček, Jaroslav (advisor)
Bachelor thesis introduced deals with Arc welding of stainless steel. With welding technology, used by company DIAMO, the connected pipes, flanges and plates are for guiding the Sodium Sulphate solution, which is obtained as by-product in production of Uranium. Corrosive attack and weld cracking occurs in the short period of time due to the chemical reaction. Based on information about materials, used additional materials and welding technology used I have evaluated materials with susceptibility to the corrosion and the formation of hot cracks. Using tests and calculations I have examined the susceptibility of austenitic stainless steel to intergranular corrosion. Austenitic-ferritic stainless steel was also used as a theoretical solution for larger spectrum of materials. After calculations and evaluations of the trial tests I have conducted discussion and recommendations for use in practice.
|
guest ::
