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39 Uppsatser om Electrode melting - Sida 1 av 3

Analys och modellering av ljusbåglängdsregleringen i pulsad MIG/MAG-svetsning

This master thesis deals with problems in the arc length control in Pulsed MIG/MAG Welding. The main problem is that it is not possible to measure the arc length. In the present solution the voltage over both the electrode and the arc represents the arc length. To improve the arc length control a model of the Electrode melting has been built. One output from the model is the voltage over the electrode and with this voltage together with the measured voltage it is possible to calculate the voltage over just the arc.

Hur fungerar en glaselektrod?

To understand the glass electrode needs knowledge from more than one level. The construction ofthe glass electrode is one part, an other is the composition and structure of glass. The Nernstequation have an important role, but also the sources of errors in the analysis and the calibration ofthe glass electrode. Focus for this article is how the glass electrode really works and how Gibbs freeenergy made the potential dependent of the concentration of H+and gives the logarithm to thefunction. Nikolskii's ion exchange theory starts to explain the question about how the potentialcreates and Baucke's dissociation mechanism made it more explicit.

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.

Höjdförändringar på Lomonosovfonna, Svalbard, 1996-2012

The climate changes and the global warming have a great impact on the Arctic environments. This partially depends on that the albedo is getting lower when snow and ice is melting and exposes more and more dark surfaces of the land and sea. This leads to a feedback effect; the melting accelerates because dark surfaces attract more sun radiation. Because of the heating the glaciers in Arctic retreat. The purpose of this report is to obtain an eventual change in elevation on the glacier Lomonosovfonna that is located on Svalbard by comparing elevation data collected by NASA and GPS data from 1996-2012.

Askans inverkan på beläggningstendensen i ett biobränsleeldat kraftvärmeverk och växtplatsens påverkan på askegenskaperna :

This report was written by Sofia Ericson and describes the degree thesis with the title: ?Connections between the growing site of bio fuel, the chemical composition of bio fuel ash and the deposit growth in a bio fuel fired boiler.? The purpose of this degree thesis was to avoid melted deposit growth in the bio fuel fired boiler at ENA Kraft in Enköping. Potassium and sodium are known to lower the melting point of bio fuel ashes and are therefore not wanted in the trees in higher amounts than necessary for the growth. Silicon is also known to be important for the deposit growth but it is not possible to say in general if higher or lower contents of silicon is better. The relation between silicon and other chemical substances is more important than the total amount of silicon.

Utveckling av metod för utvärdering av synnervens funktion hos häst :

VEP, visual evoked potential is an electrophysiologic test that can be used for evaluating the higher visual pathways. The aim of this study was to investigate if it is possible to adapt this method to horses. This method could have a clinical use in addition to the existing diagnostic methods that are available to evaluate vision in horses. Firstly, this study contains a summary of relevant studies done on animals and, secondly, an experimental part where the possibility of recording VEP in nonsedated and sedated horses is investigated and where to position the recording electrode to obtain the best results. Our results show that it is possible to record VEP in horses in a clinical setting. VEP was best recorded in the sedated horse to avoid movement artifacts and other disturbances.

Konflikten Om Arktis

The Arctic region has not been a topic of discussion or a reason for a conflict in the past, but with the development of environmental issues which has resulted in melting of the ice, so has the interest for the region developed. This has resulted in a conflict over the area, with five countries as main actors. This paper investigates the five main actors? goals with increased influence in the area, using the thoughts of Rational Actor Model, with states as utility-maximizing actors and foreign policy as the expression of national interest. Furthermore the paper investigates the means of getting to the goal, what kind of tools they use.The paper shows that all of the countries are interested in the economically benefits that are buried under the melting ice and the short cuts in sea routes that will be a possibility to use ones the ice melt more.

Fireball 2 : Energieffektiv fiber produktion

The development within the textile industry is always ongoing with development of new andbetter textiles, which often mean the use of non-natural materials like polyester. This doesn?t lineup with the work shared around the world against an improved environment, so the idea came touse a form of linen fibers instead of polyester as the reinforcing material together with cotton.The idea was to use flax, linen of low quality, which is seen as a waste product and garbage inthe production of high quality linen and flax seed oil. This flax of low quality needs to beseparated before it can be used in cotton spinning machines. Fireball 2 is just that, a process toseparate flax fibers through the treatment of a technique called electrohydraulic discharge.The thesis works goal is to evaluate the Fireball 2 process ability to separate flax fiber.

Maskinskydd på rullriktverk

ESAB is a world leader in production of welding consumables and equipment. The company manufactures, among other things, welding electrodes. A roller straightening unit is used in the cutting process to straighten the wire, which the welding electrode consists of, by adjusting some of the rollers during operation. According to ESAB?s standard and the European machinery directives, moving parts of machinery, such as rollers of the roller straightening unit, must be out of the operator?s reach.

Maskinskydd på rullriktverk

ESAB is a world leader in production of welding consumables and equipment. The company manufactures, among other things, welding electrodes. A roller straightening unit is used in the cutting process to straighten the wire, which the welding electrode consists of, by adjusting some of the rollers during operation. According to ESAB?s standard and the European machinery directives, moving parts of machinery, such as rollers of the roller straightening unit, must be out of the operator?s reach.

Att skapa konserten; Melting, Forming

Som frilansande musiker, kompositör och bandledare vill Miranda Bjerking Raeder utforska hur en konsert kan bli en större upplevelse om man tillsätter bildkonst och dansare tillsammans med bandet Black Dough på en scen. Hon vill se hur scenuttrycket växer och får mer substans när det utmanas till att vara mer storslaget. Några av frågorna som hjälpte henne att starta sin resa är: Hur kan jag sammanföra musik, bildkost och dans utan att förvirra publiken? Varför är det viktigt för mig att göra en konsert av denna form? Vilka problem och kompromisser stötte jag på i projektet? ochVilka nya perspektiv och erfarenheter öppnade sig för mig under arbetets gång?.

Canine S- and M/L- cone electroretinograms

Full-field flash electroretinography is an electrodiagnostic method used to examine the function of retinal cells. Light stimulation of the eye elicits electrical potentials in the retina. By aid of a corneal electrode and a reference electrode close to the back of the eye, the electrical potentials can be recorded and presented as an electroretinogram (ERG). ERGs driven by mainly one type of cones can be used to examine the function of a single cone class. In human beings, studies have shown the cone class sensitive to light of short wavelengths, the S-cones, to be more vulnerable to acquired damage than the other cone classes (Daley et al., 1987; Gouras et al., 1993; Greenstein et al., 1989). Dogs have two cone classes, S-cones, and M/L-cones (most sensitive to medium to long wavelengths).

Medeltid i samtid : Salvestaden en rekonstruktion i mellanlandet

The Middle Ages in contemporary time ? Salve City; a reconstruction in the Between Land is an essay dealing with the reconstruction of medieval Kalmar. The Salve City is a melting pot of such diverse fields as archaeology, pedagogies, reconstruction, historical tourism, regional development policy et cetera. Together, these parts form a space for research and mediation, business and pleasure, a place where commercialism and historical tourism can function alongside with history enthusiasts and entrepreneurs. Both pros and cons of the use of a reconstructed part of medieval Kalmar are debated..

3D-skrivare ur ett tillverkningsperspektiv

I detta examensarbete har en studie genomförts av hur väl 3D-skrivning kan tillämpas i Volvo Cars i Skövdes produktion. En litteraturstudie har genomförts för att åskådliggöra de olika 3D-skrivningsteknikerna och deras användningsområde. För att på ett överskådligt sätt jämföra de olika teknikernas duglighet har en bedömningsskala utvecklad av Nasa använts. Denna skala benämns som Technology Readiness Level (TRL). Den teknik som bedöms som mest lämplig med avseende på fullskalig produktion samt prototyptillverkning är Selective laser melting (SLM).För att åskådliggöra fördelar med 3D-skrivare har en förenklad 3D-modell av Volvos cylinderblock I5D modellerats.

Förbränning av träpellets och pelleterad halm i en 40 kW rosterreaktor

The project focus on combustion of softwood pellets and pellets in a 40 kW grate fire reactor at TEC-Lab. Dept Applied Physics and Electronics at Umeå University. Experiments were performed at four primary airs to fuel ratios (0.7 to 1.3), where aspects such as temperature profile, levels of gases (CO and NO), sintering-/-slagging and unburned fraction of the ashes were studied. Four different fuel loads were used for wood pellets (10, 20 and 30 kW) and one fuel load for straw (10 kW). Combustion of straw proved very difficult to ignite, and also led to other combustion-related technical problem such as slag formation due to the relatively low melting temperature-/-slag temperature of the straw.

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