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553 Uppsatser om Grip strength - Sida 10 av 37
Optimering av sintrade kugghjul
Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.
Stamskador i gallringsbestånd
This study was conducted on a property with a thinning machine team. The purpose was to investigate in which machine, the harvester or the forwarder, that caused most damage to the trees in six different stands. Different factors, related to the damage frequency in the stands, were checked out. For example: basal area per hectare, thinning strength, tree diameter and the rate of production.
The harvester drivers were also interviewed about how, when and why stem damages occur and how to minimize them.
The study stated that 4.3 percent of the trees were damaged. Out of these 88 percent was caused by the harvester and the rest, 12 percent, by the forwarder..
Utveckling av hjälpmedel för rörelsehindrade : Air Grip-1305
Examensarbetet är en vidareutveckling av ett föregående års arbete vars mål var att skapa en 3D-printad modell av en vakuumlift. Ett hjälpmedel för rörelsehindrade för att plocka upp föremål från marken eller trånga utrymmen. Med det som utgångspunkt har författarna tillsammans med E.MIL Energi & Miljö valt att arbeta vidare med utvecklingen av vakuumliften åt ett mer funktionsinriktat håll. Syftet med arbetet är att göra tester, analysera ingående delar och tillslut skapa en funktionsmodell på vakuumliften som tilldelats arbetsnamnetAG-1305. Genomförandet och metoden har till största del berört tester på två befintliga fläktar, en radialfläkt och en axialfläkt. Flertalet tester har genomförts med ett antal olika vanliga föremål i hushållet.
Fågel fisk eller mittemellan?
The project is a thesis which intends to strengthen the form language and increase the user friendliness of an International Moth. This is a single handed dinghy with only one sail. It sails on two hydrofoils and receives a very high speed compared to its size, and are therefore often referred to as ?the Formula One on water ?. The result is a new concept where the aerodynamic forces have been used to stabilize the boat and relieve the hydrofoils.
Högtrycket-Initierande undersökning av nytt limträmaterial
The present study examines a new production line of glue-laminated wood (glulam). The glulam is produced from non-planed boards of spruce, which also is convex, that is pressed together with high pressure during the gluing. According to a economic calculation, the material has a economical potential mainly on account of the absent planning. The study mainly found out that the shear strength of the material tolerated the demanded values in standard SS-EN 386, but the delaminating values did not. Since there are more areas to be studied around the material, the prospect to achieve the right delamination values is seen as positive..
Behandlingsmetoder vid iliotibialt friktionssyndrom: En litteraturstudie
Iliotibialt friktions syndrom (ITFS) är en av de vanligaste överbelastningsskadorna som drabbar knäet. Traditionellt har skadan betraktats som ett friktionssyndrom, senare studier har dock hävdat att en kompression av underliggande fettvävnad är orsaken till diagnosen. Etiologin och patologin bakom diagnosen har därmed inte kunnat fastställas. Kliniskt tillämpas stretching, styrketräning av höftabuktorer, neuromuskulär korrigering och myofaschiella behandlingsmetoder i rehabiliteringen av ITFS. Syftet med denna litteraturstudie var att sammanställa det vetenskapliga underlaget för behandlingsmetoder vid iliotibialt friktions syndrom.
Konstruktion av statorstomme för synkrongenerator : Förslag på design av statorstomme för användning i vertikalaxlade vindkraftverk
This thesis describes a conceptual design of a support frame for a synchronousgenerator used in a vertical axis wind power plant. In this system the generator isplaced on ground level. The thesis also considers the design of housing for thesupport frame and generator. The concept presented in this report is based on anearlier design. Besides geometric design, simplified simulations has been run in orderto optimize some of the parts included in the construction considering naturalfrequencies and structural strength.The result is presented as CAD-models andan assembly drawing..
Silikonprodukter för vardagsbruk
The aim of this thesis is to practice the theoretical methods that are concerned during the product development process of two new products. The theoretical concepts that embody the two products are created out of a product specification which is given by a commissioner with a private interest. The primary tasks of the design of the concepts are aimed on the products shape, which is to be created as a flexible structure by using silicon rubber as material.The storage box is a further development of the already known food storage box, or lunch box, which is common used in consumer kitchens. The main idea is to design a flexible product by using silicone rubber. It will able the storage box to be compressed when it is not used, be storage friendly and not consume more space than necessary in a storage compartment.
Utvärdering av infästningar i sandwichkonstruktioner för fordonsapplikationer
The automotive industry is increasingly studying lightweight solution in their designs, also rational production and low costs in materials and manufacturing methods are of great interest. This thesis consisted in the practical evaluation of anchors for sandwich panels. The object was to study loads of shearing and pull out of the plane. The experiments were carried out on panels made up of 1mm aluminium coatings and 50mm extruded polystyrene (XPS) at its core. As the fasteners used simple methods such as blind rivets, screw and glue.
Punktlasttestning av olika bergartstyper i Kiirunavaaras liggvägg
Examensarbetet ingår i den slutliga delen av kandidatutbildningen i naturresursteknik och utgör 15 högskolepoäng. Utbildningen är inriktad mot geologi och det avslutande arbetet ska ha anknytning till ämnet. Under våren 2012 presenterade representanter för LKAB förslaget att basera examensarbetet på att dokumentera hållfastheten hos bergarter från Kiirunavaaras liggvägg med hjälp av punktlasttestning. Tidigare undersökningar av hållfastheten hos bergarterna i Kiirunavaara har främst gjorts genom enaxiella tryckhållfasthetsmätningar. Det finns ett behov av att undersöka hållfastheten hos bergarterna i Kiirunavaara då gruvbrytningen sker djupare ned i jordskorpan och kraven på säkerheten ständigt ökar.
Lyftanordning för kraftuttag
This thesis has been developed inassociation with Strängbetong AB, Sweden.A few years backCementa AB introduced a new type of cement on the Swedish market: Byggcement,which is a Portland Limestone Cement. This type of cement is better for theenvironment and cheaper than Rapid Hardening Cement which is used today at SträngbetongAB.Strängbetong AB isvery interested in a change of cement in the factory and wants to know what ittakes to make a transition from Rapid Hardening Cement to Byggcement.This final projectaims at investigating how the workability and strength development are affectedby a transition from the existing cement to Byggcement and how we can change theproperties of the concrete by adding different types of superplasticizers. Laboratory and factoryexperiments were made, to investigate the transition..
Arbete över företagets gränser : En studie av organisationstillhörighet för konsulter i bemanningsföretag
Since the late 1900s, the consultancy has taken a firm grip on the labor market. The consultants' work profile has been secured through agreements such as guaranteed wages. The collective has been shattered as well as higher demands are required of the employee. This results in higher work demands, workload, a reduced staffing resource and hopeless wages which can lead to health problems and depressions. Previous research shows that consultants find it stressful to be associated with two companies and some clients can also point out consultant through different attributes.
Möjlig kvittblivning och eftermarknad av ridbaneunderlag - topplager
The aim of this study is to find information about what to do when riding arena footings are worn-out. Especially, the surface layer of riding arena footings is very interesting because of its importance of giving grip in every step for the horse, as well as shock ab-sorption. Generally, surface layers are containing several different parts in order to achieve desirable properties. These different parts can consist of organic material or in-organic material (mostly gravel). Gravel and many other materials in the top-layer are environmental friendly, and therefore, easy to get rid of.
El Niño Southern Oscillation och dess atmosfäriska fjärrpåverkan.
This paper is a literature study aiming to describe scientists newest theories andknowledge concerning the El Niño and Southern Oscillation. Firstly I have described the?normal? conditions with rising and sinking air in Hadley- and Walker-cells in theequatorial Pacific and from there moved on to explaining the reversed circulation patternsand higher sea surface temperatures (SST) leading to rising air and anomalousprecipitation in eastern Pacific constituting the El Niño phenomenon. My outermostinterest regarding El Niño has been the associated teleconnections, especially in nontropicalareas. I have described the El Niño effect on the Indian summer monsoon, ontropical cyclones and on storms and precipitation on higher latitudes.
Konstruktion av pressfixtur : För sidoplåtar till gripare G40HD
Det här examensarbetet gjordes för Cranab i Vindeln. Cranab tillverkar gripare för det mekaniserade skogsbruket, som används för att samla upp och förflytta avverkat timmer. En gripare består av två huvuddelar, gripklorna samt en vagga. Vaggan är uppbyggd av flertalet olika delar, varav två sidoplåtar, en höger samt en vänsterplåt. Sidoplåtarna skärs ut i en laserskärprocess och bockas i en pressmaskin, för att sedan svetsas samman.