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216 Uppsatser om Steel strip - Sida 13 av 15

Vätedriven förbränningsmotor : Klarläggande av framtida hållbarhet

Today when new and harder demands on CO2 emissions are developed, vehicle manufacturers must work to develop new engine solutions to new kinds of fuels to replace fossil fuels. A fuel that could be applied is hydrogen. When hydrogen is combusted only water vapor occurs. Hydrogen is known to be explosive and flammable. These properties are both good and bad for combustion.

Effect of plant maturity at harvest of haylage on digestibility and faecal particle size in horses fed forage-dominated diets

Time of harvest affects nutritional value and digestibility of haylage since plants are in different developmental stages. The aim of this study was to examine the effect of plant maturity of haylage cut in June, July and August on digestibility and faecal particle size in horses.Forage and faecal samples used for the analysis of apparent dry matter digestibility (DMd) and particle size distribution in faeces were from a feed-study performed in the autumn of 2009. Twelve horses were used in the study, divided into three groups in a change-over experiment. Each group was fed haylage harvested in June, July or August during three periods. Faecal grab samples were taken from each horse and pooled so that one sample represented one horse during one period.

Komfortsanalys med hänsyn till vibrationer orsakade av människoaktiviteter. : Ett modernt dimensioneringsproblem för huskonstruktörer

Comfort analyses regarding human induced vibrationsIt is not too common among civil engineers in Sweden to perform comfort analyses considering the vibrations caused by human activities. In addition, the Swedish standards lack requirements to be used for comfort analyses in design of floor-systems. The demand for large spans in combination with slender slabs, is today a reason to investigate the floor-system constructions, in order to prevent disturbing vibrations and oscillations.The purpose of this thesis is to create a guide for how a comfort analysis, considering vibrations, should be implemented. Göran Svedenbjörk who is an expert in structural dynamics has been interviewed where he presents his latest project Värtaterminalen and answers some questions about vibrations due to human activities.Floor-systems, consisting of concrete slabs supported by steel or concrete beams, have been investigated with simulations in the finite element program Abaqus. In the simulations, the influence of various factors on the natural frequency of floor-systems and the acceleration level caused by dynamic loads, is studied.

Framtagning av beräkningshjälpmedel för tvärkraftbelastade förband med förbindare av metall.

The governing set of regulations for structural engineering in Sweden used to be Boverket, BKR. However in the beginning of the 21st century a changeover to new regulations, the Eurocodes, started.The transition was completed in year 2011 when the Eurocodes became the mandatory design work policy for all countries within the European Union. The Eurocodes were implemented to simplify and remove potential barriers to trade that may exist when countries have different design rules.  Since the changeover it has been important for all construction companies to update their knowledge base and their design software.When comparing the two calculation processes they seem similar, but there are a couple of differences worth noting.  With the new regulations, engineers will find that the process when designing joints in timber structures has changed.  What used to be a fairly easy and straight forward calculation procedure has now become tedious and time consuming.The objective of this degree project is to present a product, a dimensioning tool that will help structural engineers when computing lateral load carrying joints in timber structures.The degree project is made up of two parts where the first part is the written report describing the background and theory behind load carrying computations. The second part of the project is the actual dimensioning tool which includes several worksheets in Microsoft Excel. The program treats single and double shear connections of the following:Nail jointsScrew jointsSteel plates (thick and thin types) The user can edit the following parameters:Type of plate/ number of shearsStrength class of timber membersMember and plate sizeType of fastenerDiameter of fastenerLength of fastenerYield moment of fastenerkmod and partial factors for design load carrying capacityThe dimensioning tool was created and developed in collaboration with structural engineers at the company Byggteknik AB.

Utveckling av Materialförsörjning : En studie av Sandvik Coromants försörjning av stål

This report is a master thesis performed by Adam Lundin at the company Sandvik Coromants production facility in Gimo. The work started in January 2013 and went on for the duration of 20 weeks, which is equivalent to 30 hp. The project was executed at the department GVR10. The scope of the project was to create a base for improvements in the purchasing process of direct material to the production. The background to the project was that the centralized purchasing department has gone through changes and decision was taken to decentralize the purchasing of direct material to Gimo.

CE-ma?rkning av produkter under byggproduktfo?rordningen

The purpose of this study is to achieve an understanding of how a CE- marking process is conducted and to identify the relevant factors that must be considered in such a process. We have conducted our study at Lo?vhults Svets & Smide AB (Lo?vhults) in Skruv, Sma?land Sweden, which are manufacturing brackets for small covering constructions.To understand how a CE-marking process is conducted several documents and provisions have been reviewed to achieve a basic understanding and insight of the subject. It thus led to that guideline ETAG 015 were studied and the factors to be considered in the CE-marking of brackets were identified. Together with Jan-A?ke Johansson at Lo?vhults we agreed on four different brackets to investigate for a potential CE-marking.

Redesign av reduktionsutrustning i asselvalsverk inom stålindustri : Ett examensarbete utfört på konstruktionsbyrån BEKAB mot stålindustriföretaget Ovako

Intresset för sömlösa stålrör med stora ytterdiametrar i förhållande till tunna väggtjocklekar har ökat tillsammans med att högre hållfasthet i olika stålsorter tillkommit. Detta gör det möjligt att tillverka lättare, billigare och mer materialeffektiva stålprodukter med samma eller högre hållfasthet som tidigare.Denna nya utvecklingsriktning medför förändringar och utmaningar i en av företaget Ovakos produktionslinor i Rörverk 5 Hofors, vilket de har behov av att samarbeta med maskinkonstruktionsföretaget BEKAB för att utvärdera och utveckla.I Ovakos produktionslina i Rörverk 5 finns en del av ett asselvalsverk som kallas för "förreducerare". Denna del av asselvalsverket ser Ovako ett stort intresse i att utvärdera och utveckla för att bättre anpassas till den nya utvecklingsriktningen.  En känd utmaning hos förreduceraren sen tidigare är att den från början är framtagen för att reducera ner ett kvalitetsproblem hos rörprodukterna som kallas för trattbildning. Projektet fördjupar sig därför inom trattbildning för att bättre förstå grunden till förreducerarens nuvarande design för att därefter genomföra en redesign av förreduceraren.I en nulägesanalys av nuvarande förreducerare framkommer ett flertal olika produktionsutrustningsproblem med tillhörande kvalitetsproblem hos rörprodukterna. Projektet väljer därmed att fokusera på de produktionsutrustningsproblem som ger störst effekt för förreduceraren om de löstes.

Varmformade eller kallformade konstruktionsrör ur ett lönsamhetsperspektiv : Undersökning av ekonomisk differens i valet mellan VKR och KKR

I Sverige kan VKR (varmformade konstruktionsrör) vara 15-23 % dyrare än KKR (kallformade konstruktions­rör) av samma tvärsnittsstorlek. Trots detta lägre pris på KKR har det upp­skattats att i Svensk stål­byggnation används endast 5 % KKR, av det totala användandet av VKR och KKR. I detta examensarbete har det först undersökts vilka skillnader i egenskaper som finns mellan VKR och KKR. Därefter beräknas prisdifferensen mellan de två profiltyperna när de utsätts för en centrisk tryckkraft under likadana förhållanden. Målet är att ta reda på vilket som är det mest ekonomiskt lönsamma alternativet i valet mellan VKR och KKR.Tryckkraftskapaciteten med hänsyn till knäckning för alla profilstorlekar i Tibnor konstruktions­tabeller har beräknats för varje möjlig kombination av tio olika längder mellan 1 till 10 m, tio olika laster mellan 100 till 1000 kN och två olika upplagsförhållanden, ledad i båda ändarna eller fast inspänd i båda ändarna.

Undersökning av svetsegenskaper för svetsning med rörtråd kontra homogen tråd

Welding is a common method for joining of metal or plastic construction parts. This report describes several different weld methods in general terms. The report focuses on the GMAW method, specifically MAG welding.A case study has also been performed for the company Wenmec. The task received from the company was to compare the mechanical properties of joints welded with the tube electrode called Nittetsu SM-3A and joints welded with the homogenous electrode called ESAB Aristorod 12.63. Both types of weld joint were welded with the MAG method with an Argon based shielding gas with 18% CO2.

Slöserijakt i betongdjungeln : En tidseffektivisering av monteringsprocessen inom stål- och betongprefab

The different aspects of each individual construction project such as the general conditions, design and economic restrictions as well as many more factors mean it is difficult to standardize building processes or plan in detail based on past experiences. As a result operational efficiency is often reduced, and unnecessary waste is generated. To make an organization more efficient and therefore reduce waste production everybody involved needs to appreciate and understand the improvements that can increase the organization?s efficiency. To investigate these improvements a time study was performed on two different construction sites, both of which involved buildings being constructed of prefabricated steel and concrete elements.

Utredning av energieffektiviseringspotential i ett flerbostadshus : Avseende på injustering av värmedistributionssystemet och installation av värmepump

The different aspects of each individual construction project such as the general conditions, design and economic restrictions as well as many more factors mean it is difficult to standardize building processes or plan in detail based on past experiences. As a result operational efficiency is often reduced, and unnecessary waste is generated. To make an organization more efficient and therefore reduce waste production everybody involved needs to appreciate and understand the improvements that can increase the organization?s efficiency. To investigate these improvements a time study was performed on two different construction sites, both of which involved buildings being constructed of prefabricated steel and concrete elements.

Giraffens blodtrycksreglering

Through previous studies during my education, I have experienced that chemical deicing road salt is a known problem, mainly in southern Sweden. Road salt causes damage to the environment and also damage to vehicles and structures such as bridges, etc. Road salt causes vehicles and steel constructions to rust, leading to increased costs for repairs of damage to structures. Road salt also causes damage to the plants and the economy to suffer, when plant material and soil needs to be replaced. In order to get closer to a solution, I put up three questions.

Med en vilja av järn och nävar av stål : Hertig Karls väg till makten sett ur ett machiavellistiskt fursteperspektiv

In 1513 the Florentine humanists Niccolò Machiavelli composed one of the most famous, but also ambiguously interpret, work in the history of politics, Il Principe. Machiavelli´s book The Prince revealed the true nature of politics in Italy in the beginning of the sixteenth century and gives very straightforward advice on how to act to become a successful and powerful political being. Machiavelli´s creation and insights in the reality of politics have be much discredited and condemned in its lack of moral consideration and violent nature. Still it has been read under the centuries with a fascination and eager to understand the structure of power and how to master it. My purpose with this study is to apply this Machiavellian idea of the capable prince on to the earlier research of the Swedish duke Karl, later on King Karl IX.

Effekter av ljus på värphönsens aktivitet och koldioxidavgivning i ett försöksstall

Få faktorer, förutom fodret, påverkar hönsen så mycket som ljus. För djurens välmående och produktion och för lantbrukarens totalekonomi spelar valet av både ljuskälla och intensitet stor roll. Eftersom lagstiftarna vill få in dagsljus i allt större utsträckning till fjäderfä är det lämpligt att studera hur bra höns trivs i ljus som påminner om dagsljuset och om detta ljus har negativa effekter. Studien gjordes med tre olika ljuskällor och med olika ljusintensitet. De olika ljuskällorna var glödljus (GL), lysrör med varmvitt sken (VV) och lysrör med dagsljusspektra (DL). Avsikten var att se hur mycket djurens aktivitet ökade med ökad ljusintensitet och om det var skillnader mellan de undersökta ljuskällorna.

Förslag till bebyggelse och park i kvarteret Seminariet i Uppsala

In the urban planning debate of today, two strategies for city development stand out as each other's opposites, urban sprawl and smart growth. This thesis concerns a development project of the latter kind and aims to give an alternative proposal to new buildings and a park in a Swedish city block. The term sprawl is used for new developments on virgin soil on the outskirts of cities leading to a city spreading, while smart growth stand for increased city density through development on re-used land within the city boundaries. The latter are often seen as more sustainable in many levels and are also shown to have positive effects on a number of city functions. At the same time smart growth has negative consequences on other aspects of the city such as public open spaces.

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