|
|
Study of durability of wood glue bonds against increased temperature
Kučera, Vít ; Vejpustek,, Zdeněk (referee) ; Vaněrek, Jan (advisor)
In this time are for design of wooden elements available simplified procedures for fire modeling which defines ČSN EN 1991-1-2. But it is not experimentally tested the impact of adhesive on the final value of fire resistance of laminated panels. This diploma thesis solves basic normative practices that could explain the durability of glue bond against increased temperatures. in the practical part will be undertaken to experimentally assess the impact of various kinds of adhesive-based (epoxy, formaldehyde, PUR and EPI) on the glued bond durability against increased temperature. Glued joints that will be subjected to gradual temperature exposure in order to assemble the dependence of the temperature influence on the final strength of the joint according to the type of adhesive.
|
|
|
Hodnocení historických konstrukčních spojů během vývoje úložného nábytku, jejich využití a optimalizace v současných podmínkách.
Záborský, Vladimír ; Gaff, Milan (advisor)
Dizertační práce zpracovává historický vývoj konstrukce a použitých materiálů úložného nábytku od 17. až po začátek 20. století a jej propojení (aplikaci) na současnou nábytkovou tvorbu.
Zaměřuje se na rozbor vlastností spojů používaných ve výrobě nábytku. Na vybraných typech spojů nábytku budou vykonané experimentální testy, kde se bude zkoumat vliv rozměrů jednotlivých částí konstrukčních elementů vybraného typu spoje a druhu dřeviny na pevnost nábytkových spojů. Rovněž se bude zkoumat vliv typu použitého lepidla. Vybrané druhy lepidel budou určeny na nábytkové konstrukce.
Jednotlivé pevnosti vybraných nábytkových spojů budou analyzovány s výpočtovým modelem pomoci metody konečných prvků. Pomocí počítačové simulace se budou jednotlivé typy nábytkových spojů porovnávat, s cílem najít nebezpečné koncentrace napětí. Tyto údaje poskytnou pro konstruktéry informace, kde je nutné daný materiál zesílit, případně zvětšit geometrické parametry konstrukčních elementů. Předpokládaným výstupem předkládaného projektu je návrh nových geometrických parametrů konstrukčních elementů a korekce dlouhodobě zažitých nedostatků uplatňovaných při tvorbě spojů.
|
|
|
Factors affecting the properties of glued joints for glues used in the wood industry
Boška, Pavel ; Böhm, Martin (advisor)
Dissertation focuses on the influence of selected factors on the properties of the bond glued by acetate polyvinyl adhesives. Factors such temperature and moisture content of the environment, the pressing pressure and cyclic stress. Despite the same type of adhesive, the properties may vary for different producers of adhesives and according to which the product is not intended. Influence will be compared to the test samples of dried beech timber with regard to shear bond strength. They will be compared properties of adhesives from different manufacturers and different destination. Test samples and test progress carried out in accordance with current standards, or largely based on. This research should help users streamline the process of adhesive bonding and reduce the production costs of the bond.
|
|
|
-
Henc, Petr ; Müller, Miroslav (advisor)
The aim of the thesis entitled "Study of some factors affecting the adhesive bonds durability" is description of factors that affect the mechanical properties (strength and hardness). The theoretical part of the thesis discusses the bonding chemical nature and bonding technology description. Various factors that may lead to degradation of bonded joint are described here too. The experimental part deals with the influence of the environment on adhesive or bonded joint. For a comparison epoxy and methylmetacryle adhesives were tested. All experiments were performed in compliance with standards ČSN EN 1465 and ČSN EN ISO 868. In long-term experiments focused on bonded joint strength change the other authors' hypotheses about the negative effect of atmospheric conditions or fluid contaminant in the liquid water form were confirmed. Experiments were also focused on the processes taking place in the bonded joints after the degradation. The process of drying under the laboratory conditions has the positive effect on the hardness of the adhesive or bonded joint strength. The results are processed by the statistical program and are summarized in the form of tables and graphs.
|
|
| |
|
|
Testing bonded steel sheet coated with zinc
Zedníček, Zbyněk ; Štroner, Marek (referee) ; Dvořák, Milan (advisor)
The aim of this master´s thesis is the design chosen for testing bonded joints on the specified galvanized steel sheet in laboratory conditions and obtaining parameters of bonded joints for application in industrial practice. Basic tests for testing bounded joints were presented in the work. Subsequently, two tests were selected and verified in laboratory conditions. The result of these tests are specific numerical values that were compared with values gained during tests linking method clinch.
|
|
|
Design of Door Frame Curvature
Merkl, Martin ; Málek, Michal (referee) ; Lošák, Petr (advisor)
This diploma thesis deals with the design of door frame curvature, meant for rail vehicle. Flat glass is adhesively bonded onto the curved door frame and due to the elastic deformation the door frame bends backwards. Hence the door frame must be bend with reserve so that the elastic deformation is covered. Finite element analysis of currently manufactured door with constant curvatere has been carried out, with this analysis it has been checked that the chosen problem approach is suitable. Design of door frame curvature is then made for door frame with combined curvature (different for lower and upper part of door frame). The aim of this thesis was to design the curvature so that after glass is bonded onto it, the door frame will have the right dimensions.
|
|
|
Effect of surface on bonded joint
Trhoň, Vojtěch ; Halamík, Tomáš (referee) ; Kubíček, Jaroslav (advisor)
This master’s thesis is divided into two parts. In the first part are these topics: bonding theory, treatment of bonding surface, types of adhesives, adhesives in the transportation industry and construction and stress of bonded joints. In the second part of this thesis is experimental evaluation of the effect of surface of material on strength of bonded joint.
|
|
| |
|
|
Analysis of adhesives in general engineering
Trhoň, Vojtěch ; Kovář, Petr (referee) ; Kubíček, Jaroslav (advisor)
This bachelor thesis is concerned with analysis of adhesives in general engineering and it is focusing on the partition of adhesives according to curring and usability. Positive and negative mechanical stress of glued joints are characterised here. The technologic process of gluding side panels of tram is elaborated in the end of this bachelor thesis.
|
guest ::
