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329 Uppsatser om Timber joints - Sida 4 av 22

Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper

At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.

Non-state actors? role in the EU forest policy making : a study of Swedish actors and the Timber Regulation negotiations

The purpose of this research is to identify how E-NGO and forest stakeholders, in the study referred to as non-state actors, have influenced the EU timber regulation; through participation and lobbyism towards the decision- makers (policy makers) at EU and national level, to achieve adjustments in the legislative text. The study also examines the relationships between the forest stakeholders, the E-NGOs and the EU-institutions, regarding communication, cooperation, informal and formal consultation where interviews were accomplished with decision-makers from the EU-institutions, forest stakeholders, E-NGOS and representatives from Swedish authorities that participated under the development of the EUTR during the period of 2008-2013. The participation and lobbying from non-state actors have most likely affected the outcome of the regulation, through alterations in the legislative text and through influencing the EU-institutions. Several factors that have affected the efficiency and timing of the influence have been identified through interviews as well as various approaches to influence the decision makers. The findings of the study may be useful for forest related interest groups that are involved in decision-making procedures at EU-level and as substance and material for further research in the subject of forest policy making at supranational level..

Förändrad aptering av massaved från 3- till 4-meterslängder vid gallring inom Södra : en systemanalys av effekter från avverkning till levererad virkesråvara

The costs of logging and of transportation with truck are dominating the total cost of wood delivered at industry. To support the profitability for the members' forestry the processing and handling with the timber has to be as efficient as possible. Increased length of pulpwood in thinning is one conduct that can result in higher productivity and/or lower costs. The study is scaled as a system analysis with the aim to exemplify the differences between working with 3- and 4-meter as standard length of pulpwood, related to biological aspects, timber receipts, cost of logging and cost of transportation with truck. Important aspects are if the change is technically and biologically feasible and economically profitable.

Metodik för utmattningsberäkning av svets i vibrationsmiljö

In this work, a method was developed and evaluated for calculating the life of welds under the influence of fatigue loads from a vibration environment. Typically, a shaker table is used for testing a component against vibration loads. The shaker table creates a vibration environment that is defined in the frequency domain by a power spectrum.Similarly, a virtual vibration table can be used to calculate the same type of load environment, which can then be used to calculate the expected lifetime. The benefit of this method is that it can be used in design, as well as in simulation of tests before physical verification tests are carried out.Today there are methods for calculating fatigue life of non-welded base material, but since many components contain welded joints, there is a need to apply this method to those types as well. To achieve this, the thesis combines two different areas, which together provide a method for fatigue assessment of welds using a virtual shaker table.The methodology is carried out by modeling the component, and its welded joints, in a finite element program.

Commercial thinning and its potential for contribution to the timber supply in British Columbia?s Interior forests : a look at Finnish and Swedish forest practices and their applicability in British Columbia?s Interior forests

Thinning is the partial removal of trees in a forest stand prior to final harvest. The term can be divided in pre-commercial thinning where little if any volume is removed from the stand and commercial thinning where removals are intended to provide a positive economic result. From a silvicultural point of view, the goal of thinning is to enhance future crop tree quality by removing low-quality stems and providing sufficient space for the accelerated development of retained ones (Huuskonen & Hynynen, 2006). The goals of this study was to see if commercial thinning could positively affect the short and medium term timber supply (MTTS) in the Interior regions of British Columbia (BC), and whether or not Scandinavian forestry practices could be adopted in the BC context. The mountain pine beetle (Dendroctonus ponderosae Hopkins) has created significant forest planning problems in BC. The annual allowable cut (AAC) was raised to capture beetle-killed timber while still merchantable.

Teknisk utredning av skärutrustning till skördare : En analys av den svenska marknaden

Husqvarna is a world leading producer of chainsaws with a well-established brand name. Husqvarna now has an interest in investigating the possibiltiy to expand their production of chains and guide bars to include cutting equipment for timber-harvesters.This project is a technical study which aims to answer questions about cutting equipment for timber-harvesters that have been decided in cooperation with Husqvarna. The questions have mainly been focused on forces, cutting speeds, service and maintenance -as well as general questions regarding the size of the Swedish market.Two methods have been applied to answer the questions. Interviews with retailers of harvesters, producers of harvester heads and harvester drivers.The main findings in this project show that there is a relatively small selection of harvester chains on the Swedish market. In contrast to the selection of harvester chains the selection of guide bars is quite large.

Lagerkostnadsarbete i teori och praktik: En fallstudie av lagerkostnader på ett sågverksföretag

This thesis investigates how inventory management is practiced at a Swedish sawmill company, how practice differs from theory in this field and how the company could make more use of this theory. To do this we have performed a study on relevant literature and compared our findings with a field study on Moelven Valåsen AB. Our analysis shows that a large gap between theory and practice exists. We identify several reasons to this, including some sector specific problems when calculating cost rate for timber inventories. Suggestions on solutions to these problems and an example of how a cost rate can be estimated with relatively simple means are presented.

Produktionsskillnader och virkesskador med olika typer av matarvalsar :

Earlier investigations showed that damages on timber from feeding rolls could be within the lower classes of damage according to VMRs classes. Knowledge about differences in productivity between kind types and aggressive types of feeding rolls is necessary because it should influence the question about damages on timber caused by different feeding rolls. In this study the production and timber damage in a harvesting head were evaluated at three levels of pressure (8, 10 and 14 MPa) on the feeding rolls, and with three different types of rolls. One type, the rubber cushioned steel plate roller had 10 mm studs and rubber damping, one ?middle? type made of solid steel with 14 mm studs, and one aggressive type, also made of solid steel with 18 mm studs.

Limnologen : Inblick i svenskt träbyggande

I Sverige fanns, mellan 1874 och 1994, ett förbud mot att bygga bostadshus med fler än två våningar i trästomme. Under denna tid försvann större delen av hantverks- och ingenjörskunnandet och man fick därför börja från början då förbudet hävdes. Byggandet gick till en början trögt, men tog fart i och med regeringens nationella träbyggnadsstrategi och utvecklandet av byggande med massivträ i början av 2000-talet. Limnologen i Växjö är ett bra exempel på hur långt fram Sverige ligger i utvecklingen, men det pekar också på områden inom tekniken som behöver förbättras.Den här uppsatsen behandlar översiktligt hur trähusbyggandet har sett ut i Sverige och beskriver sedan Limnologen med fokus på entreprenadform, stabilisering, brandskydd och akustik. Vidare beskrivs hur massivträtekniken har utvecklats och hur byggsystemet för massivträ har tagits fram..

Genetisk variation av betydelse för adenosinsignalering vid nydebuterad reumatoid artrit

Rheumatoid arthritis is an autoimmune disease, where joints are attacked by the own immune system, leading to chronic inflammation and destruction of bone and cartilage. Inflammation is a complex process, controlled by many different substances. One of them is adenosine, which has anti-inflammatory properties. In this project, three polymorphisms in different genes, involved in synthesis and signaling of adenosine, were genotyped for 188 patients with RA and 362 controls without RA. The results shows that for the polymorphism in A2a, a gene coding for an adenosine receptor, there was no significant difference in genotype distribution between the groups.

Monteringslösning till dörrkarm

Dooria Sweden AB is one of the main door- and doorframe manufacturers inSweden. They deliver door frames for indoor use for project oriented buildingsites, for these types of building sites the doorpost comes pre-assembled. DooriaAB wants to minimize transport to reduce impact on environment and thetransportation costs of pre-assembled doorframes, this thru simplifying themethod of assembly.The main purpose of this thesis has been to develop a prototype solution thatbrings the three parts of the doorframe together with the same properties regardingstability and tightness of joints as the current method of assembly. A profile ofdemands and wishes were created in collaboration with Mårten Dragstedt, DeputyDirector of Dooria Sverige ABBy following the chosen method the authors have been able to produce a fullyfunctional prototype that meet the demands that were put on the product. Catia V5R20 has been used as an aid during prototype construction and virtual tests.

Contortatallens roll för virkesförsörjningen på Holmen Skog, Region Iggesund : konsekvensanalys av fyra hushållningsstrategier för contortatall

Large areas of Lodgepole pine (Pinus contorta var. latifolia) were planted in the 1970s - and '80s. The purpose of the fast-growing species was to increase growth and with short rotation periods allow a rapidly increased harvest level. Today a large proportion of the young forests owned by Holmen Skog, Iggesund are covered by Lodgepole pine and an active forest management is required to spread the harvested volume over time which is desirable by a market perspective. The purpose of this essay is to investigate the possibility of spreading the harvested volume of Lodgepole pine over time.

Investeringsmodell för lastpallstillverkning vid Södra timber i Långasjö : Investment model for pallet manufacturing at Södra timber in Långasjö

Huvudmålet med detta examensarbete var att undersöka om det för Södra timber är ekonomiskt hållbart att tillverka engångspallar till pelletsproduktionens tilltänkta säckningsanläggning i Långasjö, gentemot att köpa in engångspallar från en extern leverantör. Detta gäller då för 30 000 engångspallar om året.Intervjuer togs på Södra timber i Långasjö om vilket virke som var lämpligt från företagets sida att bli av med. Detta visade sig vara brädor av 19x75 mm och 75x75 mm. Dessutom beslutades i ett tidigt skede att en engångspall med måtten 1200x800 mm är en bra lösning då detta är europastandardens mått. Olika alternativ togs fram för hur man skulle kunna ta fram materialet och sänka produktionskostnaderna och avsåg då brädor 19x75 och klossvirke 75x75.

Resultat från tre klonförsök med fågelbär, Prunus avium L, i södra Sverige :

This study was based on measurements of growth and shape of 50 clones of wild cherry, Prunus avium L, in south Sweden and aimed at finding out wether or not any of these clones are useful for commercial propagation. Initially, a short assembly of documented knowledge concerning wild cherry as a timber producing tree species was put together. The study of the 50 clones includes information gathered during the fall of 2006 from four trials located in the counties of Blekinge, Småland and Västergöland. The oldest trial, founded in Tranemåla, Blekinge, in 1992, was focused on offspring and aimed at discerning differences between provenances and at developing an adapted plant material. The other experiments were both clone trials and founded in 2002. These are based on 50 individuals selected from the offspring trial in Tranemåla.

Hallsta Pappersbruks virkesförsörjning

Competition of spruce fiber raw materials has increased dramatically in the last few years, leading to the fact that transportation costs in the current situation represents a much larger share of the total raw material cost. The Holmen-owned pulp industry Hallsta Paper Mill's location on the coast also constitutes a problem, because of the lack of raw material, which is much larger there, than for a pulp mill located in the hinterland. For a coastal industry it?s therefore natural to import much of the raw material by boat or to buy it from the timber terminals, in order to maintain good profitability. The purpose of this study was to analyze how the size of Hallsta Paper Mill timber supply area, without competition, with competition and with terminal use, affects the company ?s transport costs.

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