National Repository of Grey Literature 27 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Flaring the End of a Tube Under Static and Dynamic Conditions
Šrefl, Martin ; Samek, Radko (referee) ; Peterková, Eva (advisor)
The thesis is focused on expanding the ends of the tubes made of 1.4031 material into a cone shape for quasi-static and dynamic conditions. The aim of the research is the analysis of stress-strain condition in the area formed under the process conditions. As a technology test for expanding tubes is used a method of pushing the tube at a stationary mandrel and deformation measurement was done by 3D optical system ARAMIS. In the thesis is described in detail an experiment carried out under quasi-static conditions, the results of which yielded interesting findings. In the framework of the present study were designed and detailed engineering design and production tools designed for experimental realization of technological tests for quasi-static and dynamic conditions. Exploration in terms of the behavior of tube under dynamic conditions forming in this thesis is carried out in phase functional verification tools. The analysis of the forming process is planned in the framework of the next thesis.
Mathematical Model of Hardness Distribution inside Backing Roll
Kracík, Adam ; Horová, Ivana (referee) ; Samek, Radko (referee) ; Jandoš, František (referee) ; Maroš, Bohumil (advisor)
The aim of this work is to get the best detailed knowledge about hardness distribution in first 60 mm below the surface of backing roll. To this end, a method for obtaining multi-dimensional polynomial regression was developed and then a computer program for its processing was written.Way of finding suitable regression surfaces and their subsequent interpretation, is a pivotal part of this work.
Dynamic Properties of Combined Rivet and Adhesive Bonded Joints
Urík, Tomáš ; Samek, Radko (referee) ; Petrásek, Miloslav (referee) ; Klement, Josef (advisor)
The improvement of static properties of combined rivet and adhesive bonded joints have been proven by several authors [1, 2]. On the other side, dynamic properties of joints (for example fatigue and corrosion) significantly affect final function of structures during their service life. In this thesis, the combine joints created by blind rivets and hyper elastic sealant are solved. Complex description of dynamic properties of this particular combined joining technology has not been publicised, yet. Description of sealant layer influence on stress concentration in rivet hole regions is one of the main goal of this work. The next stage of the thesis is focused on the influence of above mentioned sealant layer on fatigue properties of combined blind rivet and solid countersunk rivet joints. Stress strain analysis of rivet and combined joints done by FE analysis and by experimental optical measurement of strain field proved that hyper elastic sealant layer has a positive effect on decreasing of stress peaks in rivet hole regions. This findings are in direct compliance with fatigue measurement of combined joint (AAPL). The influence of applied sealant in this combined joints improved fatigue properties by twenty percentage increasing of stress to failure in comparison with rivet joints.
Forming limits for the bending process of tubular components
Maleček, Michal ; Peterková, Eva (referee) ; Samek, Radko (advisor)
Currently, rotary draw bending is frequently used method in industry. Nevertheless, it has been limited for long time by different types of defects. Submitted thesis deals with the study of the influence the bending radius and wall thickness on the quality of bent. Practical part of the thesis includes experimental rotary draw bending of tubes. The work also solves determining actual values of the wall thickness; ovality, bent shapes, the section modulus in bending and the neutral axis of the tube On the basis of evaluation of criteria are then set the parameters of permissible bend
Bulk forming technology of carrier pin
Sejkora, Petr ; Samek, Radko (referee) ; Forejt, Milan (advisor)
Diploma thesis focus on the proposal of the carrier pin production from the steel 17 021 by cold bulk forming technology with sight on the upsetting and extrusion. There were suggested two versions of the technological plan from which was one chosen as optimal. There were carried out calculation of deformation, forming and deformation resistances and forming forces for the chosen version. Machine for the part TPM 12 production was chosen on the basis of the global forming force 660 kN. Furthermore there were proposed forming tools for the second operation – feed forward extrusion. Finally there was made technical and economical evaluation.
Influences of process parameters and material on technological forming limits of given componenet
Exnerová, Jitka ; Peterková, Eva (referee) ; Samek, Radko (advisor)
Master s thesis is focused on flaring of tubes endings. There are also mentioned theoretical pieces of knowledge which relate to tubes endings by a flat edge and a cone. The following experiments performed with the own material and tools made by the author s design. Experiments in the production of the flat collar led to the speedy rotation of the sample ending. Experiments with the conical ending brought valuable results from the point of view of comparison of theoretical and measured powers, distribution of thicknesses and utilization of the deformation web to set voltage-deformation state. The dimension excent of the conical ending was limited by the formation of buckling in the cylindrical part of the tube.
Investigation and Improvement of the Bending processes of Tubes – Headrest rods
Barcuch, Jiří ; Peterková, Eva (referee) ; Samek, Radko (advisor)
The work deals with the analysis of the influence of process parameters, material factor and tools power effect to compliance with the limit shape tolerances of specified parts of bending tubes by method of wrapping. Their evaluation using statistics and the resulting recommendations for process optimization.
Bulk forming technology of carrier pin
Večeřa, Jiří ; Samek, Radko (referee) ; Forejt, Milan (advisor)
This thesis deals with a proposal of a technology for manufacturing a carrier pin made of corrosion resistant chrome steel 17 021.3. Having studied the information about cold bulk-metal forming in the available literature, I have suggested two variants of manufacturing processes. The suggested manufacturing variants consist of four forming operations which combine upsetting and extrusion. As far as the chosen variant is concerned, there have been made technological and strength calculations for the individual operations. As regards the designed technology, I have opted for the automatic multistation forming machine TPZK 25, produced by the company ŠMERAL Brno.
Evaluation of materials characteristics exploiting static and dynamical tests
Riesner, Jan ; Forejt, Milan (referee) ; Samek, Radko (advisor)
The project elaborated in frame of engineering studies branch M-STG describe characteristics of plasticity of non-anneal materials E 235, E 190 and E 220. Materials characteristic was receive by static and dynamical tests. Based on the literature study it was conducted survey of the current state of experimental techniques for high-speed deformation. The materials were designed by Holomon approximation of rigid-plastic material model without hardening. It was conducted force analyses for machine Unison MG 2790 for rewind bending and bend with compressive force considering the identified material model. It was describe the impact passive and active forces to move the neutral axis.
Conditions of failures generation when bending profiled tubes
Fišar, Luboš ; Peterková, Eva (referee) ; Samek, Radko (advisor)
The thesis describes the knowledge from a round tube bending technology, as a description of conventional and unconventional devices. There are technological parameters in relation to the creation of defects, and equations for determining the bending moment. These knowledge has been generalized and applied to solution the changes of cross-section shape and thickness in the bending of square cross-section. The solution was implemented to specific component (20x2 mm steel tube with two successive radii R57,2 and R131,5). The results of experiments shows that the material is almost rigid-perfectly plastic, in the most stressed areas has a sufficient supply of material formability. Thickness measurement was applied to calculate the approximate center of gravity changes. This shows a shift of 1.4 mm, which is negligible value for the pure bending. The end of the thesis summarizes the deficiencies of current manufacturing technology, which used mandrel is inadequate, wrong located and poor lubrication.

National Repository of Grey Literature : 27 records found   1 - 10nextend  jump to record:
See also: similar author names
1 SAMEK, Renata
1 Samek, Richard
Interested in being notified about new results for this query?
Subscribe to the RSS feed.