Production of IT case

Diplomová práce se zabývá návrhem technologického postupu pro výrobu počítačové skříně ve společnosti EMKO Case a.s. Počítačová skříň je vyráběna z plechové tabule o tloušťce 1 mm. Pro výrobu skříně byly jako nejvhodnější zvoleny technologie vysekávání a ohraňování. Diplomová práce obsahuje literární studie na tyto vybrané technologie. Na jejím základě byly provedeny technologické výpočty, návrh technologického postupu a volba strojů. Pro vysekávání byl zvolen stroj od firmy TRUMPF TruPunch 2000, pro ohraňování pak hydraulický lis od firmy TRUMPF TrumaBend 50V. Pro zvolené řešení je v diplomové práci vypracováno i technicko-ekonomické vyhodnocení.The master’s thesis deals with proposal of technological process for production of computer case in EMKO Case a.s. Computer case is manufactured from a DX51D + Z275 steel sheet with thickness 1 mm. For manufacturing were chosen technology punching and press-brake bending as the best technologies. Master’s thesis contains literary studies of these chosen technologies. Based on literary studies were made technological calculations, proposal of technological process and choice of machines. For punching was chosen machine TRUMPF TruPunch 2000, for press-brake bending hydraulic machine TRUMPF TrumaBend 50V. For chosen solution is made technical and economical evaluation.

Design of an electrically powered bending machine : case of Zimbabwe

Abstract: This paper seeks to carry out design of a small scale electrically powered bending machine for a developing nation, case for Zimbabwe. The bending of metal is of great importance in the manufacture of products such as nut shelling machines and maize shelling machines. Currently being used at Company X engineering is a manual bending machine with a single operation hence this design will help to increase the number of metals being bent, an increase in the efficiency and production. The paper deals with manufacturing or bending of sheet metal by using power operated sheet bending machine. Especially discussion made the productivity analysis of manually or power operated sheet bending machine. Considering manual operation is replaced by power operated devices. It also gives information about limitation of manually operated sheet bending machine and power operated sheet bending machine. The existing machines are limited to a single operation. The aim of the research is to increase the number of bent parts and to place an adjustable table to suit the height of the user thereby reducing back pain internal injuries in the long run. The researchers visited the Company X to gather information concerning the problems faced by the employees. Material tests which are of great value were carried out and the use of software. A Plate Rolling Machine is a machine that will roll different kinds of metal sheet into a round or conical shape and a rod bending machine will roll or bend different kinds of metal sheet into right angles or circular shapes. The research aims at making it possible to do the operations on a single machine. We recommend the machine to be automated and the use of a servo motor to reduce human injuries at the workshop. Use of oils and maintenance is of great value to increase the life span of the machine

Deformation Processes of Metallic Open-Cell Foam Supported Sheet Metals

Sandwich panel has been widely applied to enhance the stiffness to weight performance of components in many industries. The manufacturing procedure of curved metal sandwich panels typically consists of forming the sheet and core material into prescribed shapes and applying the adhesive to bond the material in shaped molds. An alternative manufacturing method is to apply the conventional sheet metal forming technique to deform the flat sandwich panel into a curved panel. However, the face sheet will significantly limit the formability of the sandwich panel. To solve the problem, one face sheet was removed in the sandwich panel to increase the formability, then the metal sheet and the metallic open-cell foam were selected as the face sheet and the core material to form the metallic open-cell foam supported sheet metals. The main objective of this study is to develop a proper forming method to deform the metallic open-cell foam supported sheet metal without failure occurring. Two forming processes, press brake bending and hydroforming, which can reduce the contact stress to avoid the structure damage were investigated. Experiments were designed to understand the possible failure modes and the failure mechanism. Through the parametric study in the experimental results, the effects of material dimensions, material properties, and test parameters were analyzed to establish a failure criterion. In addition, a finite element analysis with a proper foam model was implemented to further inspect the failure mechanism and develop a guideline for the selection of materials and test parameters. For the press brake bending process, the experiment results have shown that the supported sheet metal can be successfully bent into a curved panel within small thickness reduction. The prediction in both geometric hoop strain failure criterion and shear strain failure in the finite element analysis were matched and agreed with the experimental result. For the hydroforming process, the experimental result indicated that the major failure mode is the adhesive failure. The early adhesive failure at the perimeter of the attached foam disc caused the open-cell foam to separate from the sheet metal. The required adhesive strength to the attainable dome height relationship was given by finite element analysis

Industrial product design by using two-dimensional material in the context of origamic structure and integrity

Thesis (Master)--Izmir Institute of Technology, Izmir, 2004Includes bibliographical references (leaves: 115)Text in English; Abstract: Turkish and English.xiii, 118 leavesThroughout the history of industrial product design, there have always been attempts to shape everyday objects from a single piece of semi-finished industrial materials such as plywood, sheet metal, plastic sheet and paper-based sheet. One of the ways to form these two-dimensional materials into three-dimensional products is bending following cutting. Similar concepts of this spatial transformation are encountered in the origami form, which has a planar surface in unfolded state, then transforms to a three-dimensional state by folding or by folding following cutting. If so, conceptually it may be useful to think of one-axis bending, which is a manufacturing technique, is somewhat similar to folding paper.In this regard, the studies in the scope of computational origami, which light the way for real-world problems such as how sheets of material will behave under stress, have applications especially in .manufacturing phase. of industrial product design.Besides manufacturing phase, origami design is also used as a product design tool either in .concept creating phase. (in the context of its concepts) or in 'form creating phase' (in the context of its design principles).In this thesis, the designing of industrial products, which are made from sheet material, is presented in a framework that considers the origami design. In the theoretical framework, evolutionary progression of origami design is discussed briefly in order to comprehend the situation of origami design in distinct application fields.Moreover, the elements, principles, basics of origami design and origamic structures are generally introduced. The theoretical framework is completed with the descriptions of the concepts on origami design and origamic structures. In the practical framework, typical applications that have origamic structures in distinct industrial product fields are exemplified. Furthermore, sheet materials and their bending process are taken up separately. By means of its excessive advantages, sheet metal bending is particularly emphasized. The practical framework is completed with several case studies base on sheet metal bending. Finally, the study is concluded with the evaluation of the origamic-structured product in respect of good design principles. Furthermore, designing by considering origami design is recommended to designer to design a good industrial product

The Production of the Components on the Press Brake Machine

Práce předkládá přehled o technologii výroby součástí na ohraňovacích lisech. Je vytvořena na základě literární studie teoretického základu s doplněním nejmodernějších poznatků a příkladů z praxe. Pojednává obecně o technologii ohybu, jeho principu a parametrech, které s ohybem souvisí. Dále jsou popsány nejčastěji užívané metody výroby na ohraňovacích lisech, tvářecí nástroje, jejich výroba a upínání ve stroji. Hlavní důraz je kladen na samotné ohraňovací lisy. Jsou zde popsány různé typy ohraňovacích lisů, dále jednotlivé části lisu a nakonec je uveden i přehled nejznámějších výrobců. Pro lepší představu procesu výroby je ukázána výroba součásti na praktickém příkladu z výrobní firmy. Přínosem této práce je jednoduše popsaná technologie ohraňování a způsob práce na ohraňovacích lisech, což může sloužit pro didaktické účely.The project elaborated overview of the production technology of the components on the press brake machines. It is based on study of theoretical pricniples in literature and modern practical instances as added value. It discussed about bending technology in general, about its priciple and parameters. Then there is overview of most used methods of bending at press brake. bending tools, its process of production and tool clamping. The main emphasis is placed on press brake machines. There are discussed the main types of machines, structure of machine and last but not least there are presented selected world manufaturers of press brake machines. For a better idea there is showed production of particular component in manufacturing plant in the end. Acquisition of the project is in simple description of press bending technology and way of work on press brake machines. The useful trasfer may be for example to education.

Influence of adhesion properties on the crash behavior of steel/polymer/steel sandwich crashboxes: an experimental study

The energy absorption behavior of crashboxes made of steel/polymer/steel (SPS) sandwich sheets can be influenced by numerous parameters, such as the materials used, their thicknesses and stacking, and the adhesion properties between their layers. Therefore, in the present study, the impact of steel/polymer adhesion quality on the occurring failure modes of the crashboxes and the resulting energy absorptions are experimentally analyzed. For this purpose, axial crushing and three-point bending tests on double-hat and top-hat crash boxes were performed, respectively. Three levels of adhesion quality are investigated: none, weak, and strong adhesion strengths. Additionally, the structural crash properties, such as energy absorption and maximal intrusion, are determined and analyzed at both of the quasi-static and highly dynamic loading rates. The results of these investigations show that the adhesion strengths chosen here significantly influence both the failure modes and the energy absorption values. In particular, the structural parameters, in the case of no adhesion, are at most half of those in the case of strong adhesion. However, it is also shown that, in the case of weak adhesion, the structural characteristics are slightly reduced. Based on these results, the possibility to adjust the adhesion strength—globally and/or locally—could be used in future activities to purposefully tailor the failure behavior of hybrid crashboxes

Experimental and analytical evaluation of bending for stainless steel

Analytical calculation is one of the methods in predicting the spring-back angle after bending process. Precise predictions of spring-back angle after the bending process are the key to the design of the bending die, bending tool, and to produce the accuracy part geometry. This thesis purpose is to determine the reliability of analytical method in V-bending analysis of stainless steel by comparing the results with experimental results and the experimental measurements of Özgür (2008). The effects of significant parameters including sheet thickness and sheet anisotropy on spring-back in V-bending analysis also have been studies. The mechanical properties that provided from tensile test experiment have been used in the analytical calculation in solving the spring-back equation. Two different equations from previous studies have been used to determine the spring-back angle. In the V-bending experiment, two different test procedures (bottoming and air V-bending process) were used. The experimental results have been used to evaluate the analytical results. The results of this project shown the spring-back values for analytical calculation are generally is not in agreement with the experimental value but the graph trends obtained in this study are generally in agreement with experimental graph patterns. The graph patterns are also in agreement with the past study by other researcher (Özgür, 2008). Increasing the sheet thickness resulted increase in the spring-back angle. The orientation angle and anisotropy value R will influence the spring-back. In general, the spring-back angle is increase if the orientation angle is increase. Therefore, the 0 degree orientation angle is a suitable condition in V-bending processes because the spring-back value is smallest compared to other orientation angles. The percentage error is very high because there are some errors occur during the tensile specimen preparation, tensile test experiment and V-bending test experiment. The accuracy and precision of machine in collecting and determined the data is a factors as the higher percentage error. It is conclude that the analytical method is not suitable in sheet metal bending analysis of stainless steel. This is because, combination of various material types and process parameters make the exact prediction of spring-back difficult

RANCANG BANGUN ALATBANTU PENEKUK AKRILIK (PROSES PEMBUATAN)

LaporaniniberjudulRancangBangun Alat Bantu PenekukAkrilik. Laporaniniadalahmengenaialatbantupenekukakrilik yang digunakanuntukmempermudah para pekerjadalammembendingakrilik. Alat inimemilikibeberapakomponendenganfungsi yang berbeda-beda, dimanaalatuntuk proses penekukannyahanyamemakaitenagamanusia. Dalam proses pembuatannya, RancangBangun Alat Bantu PenekukAkrilikinimenggunakanperalatansederhanayaituGerindaTangan, BorTangan, Gergaja Kayu dan beberapaalatperkakaslainnya. Alat inimasihterdapatbeberapakekurangan, untukitumasihperludilakukanmodifikasi agar fungsikerjaalatinidapatlebih optimal

Sandwich steels for crash energy absorption applications

This thesis has examined the applicability of steel–polypropylene–steel sandwich materials for the role of axial energy absorbers, an application previously undescribed in the literature. The results show that energy absorption performance of steel–polypropylene–steel sandwich materials can be predicted to within –2% and +8%, as well as highlighting the potential for their use in automotive applications. The work has demonstrated that the deformation modes in the steel–polypropylene–steel sandwich mimic the monolithic metal crash structure, however, with smaller fold radii, hypothesised to be due to shear in the polypropylene core. It was observed that increasing the core thickness increased the radius of the folds in the structure when undergoing collapse. Though due to the variability in the folding patterns of sandwich material in the crash structures seen in this work, it could not be stated with certainty. From the physical testing, the effect of core thickness for a fixed skin thickness is also defined. The physical tests showed a linear relationship between increasing core thickness and mean crush force. Further, the effectiveness of increasing the core thickness on the specific energy absorption was identified. The testing also showed an unprecedented >60% increase in energy absorption from quasi–static to dynamic for all three thicknesses of Steelite sandwich material, a level not seen in monolithic metal crash structures. Hence, suggesting an increased strain rate sensitivity of steel in MPM sandwich materials over the monolithic steel, a property which has been suggested in the literature for tensile tests but unknown in axial crash deformation. The testing demonstrated the potential for the crushing mode to change from a desirable progressive crushing mode to an undesirable and difficult to predict progressive failure. This occurred with a 7:1 core to skin thickness ratio, though failure of the steel skin is seen at all ratios. A 70%:30% ratio of thickness for the polypropylene core to steel skin is shown to minimise steel skin failure, i.e. the individual steel skin thickness should be no less than 15% of the total sandwich thickness. Finite element analysis presented in this thesis shows a single shell element model with laminated shell theory invoked can be used in LS–DYNA to predict the performance of the steel–polypropylene–steel sandwich materials. However, there is a potential thickness limit for which the model is applicable for the single hat and backplate crash structure considered; further research would be required to increase the confidence in the model. The single shell element model was accurate to within +8% of the physical test results. An analytical solution fitted the LS–DYNA single shell element model well and showed increasing the core thickness is more effective at increasing the specific energy absorption than increasing the skin thickness. The analytical solution also shows the potential for a steel–polypropylene–steel sandwich with a core to skin ratio of 70%:30% ratio by thickness to equal the performance of high strength aluminium alloys

An Origami-Inspired Design of a Thermal Mixing Element Within a Concentrated Solar Power System

A Concentrated Solar Power on Demand (CSPonD) system heats a tank of molten salt with sunlight, storing the sun's energy thermally and generating electricity when needed using a heat exchanger. To prevent the heated salt from forming thermal gradients (reducing the heat exchanger's efficiency) or overheating (and becoming corrosive), a thermal mixing element mixes the heated salt both axially and radially. Since the mixing element can only move axially within the tank, it contains internal, radial channels to induce radial flow of the salt. These channels are constructed from tabbed wall-components, whose tabs seat into and extend past slots in the top-and bottom-plates of the mixing element. The top-and bottom-plates are constructed from multiple panels with overlapping slots, allowing the panels to form the plates when the tabs are inserted. This interlocking design allows majority of the mixing element to be rapidly manufactured at a low cost from sheet metal and simplifies transportation. In situ, the assembled components fasten together by bending the overextending tabs, minimizing the number of fasteners needed. Topics: Design, Concentrating solar powerMasdar Institute of Science and Technolog