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329 Uppsatser om Timber joints - Sida 2 av 22
Detektor på skördare för utsortering av träd med metallskrot
Fortifikationsverket which is the landlord for the Swedish national defence has a great problem in their forestry due to the relatively large amount of metal objects in their timber. These metal objects cause different types of economical losses in the timber refinement chain. To enable out sorting of logs containing metal objects already in the harvesting phase, Fortifikationsverket is interested of the possibility to utilize some type of metal detector in a harvesting head for that purpose.The goal of this study was to, with help of a case study, enlighten the problem that metal objects in timber cause for Fortifikationsverket and their customers of timber and to investigate conditions of to mount and utilize some kind of metal detector in a harvesting head at present.The saw timber deliveries by Fortifikationsverket during the time period 2003-2005 was used as a reference volume for calculations of economical losses. In this case study was included two sawmills where timber from Fortifikationsverket were delivered to for further refinement. Factors investigated were the type of damage metal objects caused in these two sawmills and the economical signification of these damages.
Timmerkvalitet hos björk i blandskog med gran
Birch is the dominant deciduous tree species in Sweden but only 16 % is found in pure birch stands. The majority of the birch (51 %) is to be found in conifer dominated stands. Swedish forest land comprises approximately of 23 % mixed stands and one problem is that for mixed stands there are few management recommendations. The underlying aim of this thesis was to study the management of mixed forest stands of spruce and birch to achieve good timber quality of birch. The study was based on a literature study and measurement in a field experiment launched in 1998 by the Swedish University of Agricultural Sciences (SLU).
Sorterar skotaren bort det timmer som skördaren har tillrett? :
The efficiency of the harvesters work is more often reviewed, than the work of the forwarders. In a local Stora Enso office the differences between the harvesters reported volume of timber, and the actual volume delivered to the industry had been noticed. Therefore, the decision was made to do a review on the forwarders work.
The review was conducted together with a worker from Vmf Qbera, who is working daily with wood measurement, in order to get a valid evaluation of the logs. Eight sites were included in the survey, and on each site 50 logs were marked. Approximately one third of the marked logs were pulpwood, and the remaining logs marked were timber.
Pottaskeframställning och tjärbränning i Femsjö socken från år 1700 till 1900 :
Femsjö is a small parish situated in Hylte municipality, Växjö diocese. The parish has a total area of 8230 ha of which 5000 ha are covered with forest. There have not been any large industries in the parish offering work opportunities for the inhabitants, so they have had to generate income from their land and the forest. Instead of going to the bank to get a bank loan the people of Femsjö parish went out in to the forest and harvested trees for timber and extra cash revenue. Production of pine tar and potash were two other ways that the residents of Femsjö parish could earn extra money for the household in order to keep starvation away.
Prevalens av osteochondros hos avkommor efter svenska halvblodshingstar : en retrospektiv tvärsnittstudie utförd med hjälp av rutinmässigt insamlade klinikdata från röntgade hästar vid ett svenskt djursjukhus
The main purpose of this study was to study the heredity of osteochondrosis (OC) in fetlock-, hock- or stifle joints within the Swedish half-bred population, using data from the regional animal hospital in Helsingborg.
A large number of horses with clinical symptoms, for example lameness, are radiographed every year at the regional animal hospital in Helsingborg. In addition, many clinically healthy horses are radiographed in order to be sold (inspection radiographed / export radiographed). This study is based on electronically stored data from horses in both of these groups of patients that underwent joint radiography at the regional hospital in Helsingborg during the years 1992-1999. The first file (inspection file) contained 1035 observations from 983 horses that had their fetlock-, hock - or stifle joints radiographed for inspection or export. The other file (clinical file) contained 6121 observations from 3800 horses that were radiographed due to clinical symptoms in the fetlock-, stifle or hock joints.
Från 2D till BIM i ett trähusföretag : Transition from 2D-CAD to BIM in a timber frame home company
A prefabricated timber frame house previously built by Villafabriken AB has been modeled in Autodesk Revit Architectural, a 3D-program based on BIM-technology. This has been done tosee if it?s possible to produce the publications that Villafabriken demands from the designengineer?s work, and examine which possible extra values that may arise compared to traditional 2D-CAD drawing.BIM is short for Building Information Modeling. Everything is stored in a single database and a change in the project file is automatically updated across the project. BIM provides more than just drawings since information from the model can be retrieved in various ways such as lists and quantity schedules.It was possible to produce the publications that Villafabriken demanded using Revit, but BIM doesn?t only mean a new way of drawing, it also require a change in the company?s process were the information from the model is being used..
Timmersorteringens inverkan på sågverksekonomin :
Modern sawmills are using the raw-material and the production-capacity more efficiently
today, due to rising raw-material prices and higher production costs. Log sweepness has a
negative effect on the sawn yield, for sawmills with straight-sawing. It is desirable that these logs could be sorted based on more criteria, if it increases value-yield and consequently the utilization of raw-material.
Bow-heights over 1 cm have a negative effect on sawn yield, since the surface of the
mantle cuts down in the sawn pattern. Some of these small bow-heights reduce the logs yield of value which affects the production planning negatively. Nearly half of all the Swedish logs have a bow-height over 1 cm.
Kartläggning av ruttplaneringsprocesser för rundvirkestransportörer
Transportation represents 10-15 % of wood supply costs. It is therefore important to improve efficiency in the transport system to decrease these costs. The aim of this study is to map the timber vehicle routing processes used by a sample of timber hauling contractors and to identify possible links between the vehicle routing process and service and economic variables. The study was carried out at Södra Skog in autumn 2008. 15 timber hauling contractors were sampled and interviewed about their work with timber transports.
Vederlagsgrundande mätning med skördare
This study was performed in collaboration with Moelven Skog AB, Örebro district. The purpose of the study was to review existing literature in order to describe the current status of harvester based measurement technology as the way to provide information for calculating payment to the forest owners. In addition to this, a short survey was conducted to find out how a switch to harvester based measurement would affect the administrative workload on timber purchasers working for the district.
The literature study shows that the harvester measurement technology is ready to use if it is combined with well-established routines for control of the harvesters, methods for automatic quality indexing of the timber and ways of creating pricelists specially adapted for harvester measurement. Pricing each stem seems to be the most promising method. Stem pricing has several benefits.
Undersökning av svetsförband med avseende på svetsgeometri, diskontinuiteter och blästring med stålkulor
Breakdowns of welded structures are usually a consequence of fatigue loading. Fatigue fractures are commonly initiated in the region close to the weld toe but can also initiate from the weld root and from discontinuities inside the weld. The purpose of this investigation was to examine the weld quality of welded joints produced at Volvo Wheel Loaders factory in Arvika. The goal of the investigation is to give a clearer insight regarding factors influencing the fatigue strength of the welded joints and thereby give a better foundation for fatigue strength calculations.The investigation is including examination of the weld geometry, weld discontinuities and the effects of shot peening. Mainly three different methods for collecting test data have been used: Plastic replicas cast on the weld profile, weld specimens from a rear frame belonging to a wheel loader of model L110E/120E and Almen testing of the shot peening.The results showed that it is not possible to control even transition between the weld material and the base material without after treatment.
Analys av GPS Timber vid Rundviks sågverk
Rundviks sågverk investerade vintern 2007 i systemet GPS Timber. Systemet som är GPS-baserat syftar till att underlätta timmerhanteringen och säkerställa att rätt timmerklass läggs i vältorna och på sågbordet. Dessutom samlar systemet fortlöpande in data angående truckarnas aktiviteter för att möjliggöra analys av vad som sker på timmerplanen.Studien syftar till att undersöka vad införandet betytt för truckförarnas arbete med timmerhanteringen samt vad systemet har för effekt på ekonomin. Med hjälp av insamlad data av GPS Timber ska analysen dessutom resultera i potentiella effektiviseringsområden rörande timmerhanteringen för att förbättra ekonomin i en relativt dyr process. Analysen har visat att truckförarnas arbete har förenklats mycket i och med införandet av GPS Timber.
The impact of the EU Timber Regulation on the Bosnia and Herzegovinian export of processed wood
Illegal logging and its related trade is of great concern around the world. The European Union Timber Regulation (EUTR) is a regulatory approach by the EU to prevent illegal timber and timber products to be placed on the European Union inner market. This means the regulation affects both actors in the member countries as well as the actors exporting timber and timber products to the EU from non EU member countries. This study aims to study the implementation process of the EUTR in Bosnia and Herzegovina (B-H), and its preconditions. Institutional theory is used to understand and explain how the EUTR affects B-H organisations? business environment, and how the organisations choose to respond to the EUTR.
Dubbskador på Alvestakubb
Mechanical harvesting may result in timber damages leading to reduced saw log quality. The initiator of this study was VIDA ? a privately owned concern operating in the value-adding process industry of forest raw materials. The aim of this study was to examine the type and amount of damages on Alvestakubb caused by the harvester head during the cutting process. The aim was also to compare the damages caused by different types of feed rollers and to evaluate the effects of temperature on damage occurrence.
Ökat flöde genom timmersorteringen vid Ala sågverk
Ala sawmill in Ljusne, Hälsingland, has increased its flow through the sawing plant during the last couple of years. The problem now is the sorting plant, as this part of the mill is now slower than the rest. A close analysis of the sorting plant was therefore necessary to be able to increase the flow through. The aim of the project was to find solutions that can lessen downtime and increase flow. The goal was to increase the flow from 650 to 925 logs through the sorting plant per hour.
Förekomst & kostnad av kapsprickor i stormaskadad skog
The aim for this study where to investigate the frequency of cutting cracks in saw timber harvested in the storm-damaged forests in regions where the storms Hilde and Ivar hit. The idea for this work came from one of the region?s biggest actors, SCA Skog and Jämtlands district. The purpose where to find out how big proportion of the saw timber that contains cutting cracks, their financial cost in lost wood value and also give advice and suggestions on how to work against the frequency of cutting cracks.
For the field-study some guidelines where used to make sure that the samples were taken under the same conditions, they were:
? The field-study must be performed under harvesting of storm-felled forest, which are horizontal/inclined trunks.
? The averaged sized tree will make it possible to harvest saw timber.
? The trunks can?t be root cut.
A methodology called in Swedish ?Trissmetoden? was used because it is the most frequent used methodology in earlier performed studies and the only one that can be used I field.
Under the field-study data were collected from 570 saw timber logs, 30 logs from each one of the tested harvesters.