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.

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.

Swedish sawmills of today suffer from unsatisfying economy with high costs and low benefits. The economical result depends on how well the sawmill can use their raw material. Iggesund Timber AB, a sawmill in the Holmen group, produces a large amount is enduse orientated products for the woodworking industry. Therefore the aim of this student thesis was to investigate the possibility of automatic enduse orientated quality grading of Scots Pine (Pinus sylvestris) saw logs by using a gamma-ray log scanner. Iggesund Timber AB has the possibility to grade logs automatically with TINA, a two way gamma-ray log scanner. Grading and classification of Scots Pine logs in Sweden today are mainly manual but can in some rare cases be automatic.

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.

The aim of this thesis was to analyse BARO WOOD AB:s timber measuring and quality sorting and to evaluate the analyse program Stockholmen. The purpose was to get a better understanding for the quality sorting made at BARO WOOD AB today, analyse differences in center board quality from logs with a good quality and logs with a bad quality, suggest new sorting criterias developed from analyses made with Stockholmen and to evaluate the program Stockholmen. All analyses are based on data gathered in a test sawing made at BARO WOOD AB in June and July 2002. The test sawing was made on four different diameter classes and every diameter class consisted out of A or M-grade logs, with a better quality, and B-grade logs with a lesser quality. The logs where sorted out with BARO WOOD AB:s existing quality criterias.

The paper, with a brief summary of timber floating in Sweden and also of some previous re-search in this field, contains a study on costs for timber-floating in the river Dalälven located in central Sweden. The public used timber-floating system in Dalälven and the historical background about this activity is described. The study is focused on the total costs for timber-floating in the public open floating system in Dalälven from 1900 to 1970, the year before the timber-floating was definitively closed down. Also the costs for separating the logs of a specific owner when they reached the point where they could be separated from the timber of other owners are analyzed..

The purpose of the rebuild of Notnäs AB Timber sorting line is to renew the existing drive and turning ends of the transport chain, which has become old. This means that Notnäs AB have problems to get new parts if the gearbox and chain are worn out. They also require that the rebuild should have a maintenance schedule for the new spare parts that will be used in the rebuild. Maintenance workers placed great emphasis on that in a rebuild it shall be a service-friendly design. The maintenance schedule used in Notnäs AB in the current situation is from Statoil and the report uses SKF formulas and recommendations in order to obtain a lubricating schedule.

This essay concerns the visual trade grading of pine and spruce.In the 1800s developed rules for sorting of wood. The rules used to facilitate the export trade.The terms of the regulatory sorting systems developed in the 1900s. While it still used some of the older terms.The essay deals with how the grading rules affect the use of wood and how the rule work and how the terminology works.Some of the terms used for sorting are O/S, Kvinta, Utskott and A,B,C,D.You sorting by counting the numbers of knots, cracks and other characteristics of each piece of wood.The sawmills have much influence in how the rules developed.Today it is often already determined in the sawmills which uses each piece of wood most have..

This report is a joint venture with SCA Skog AB in the Jämtland forest management area. The company is a major player in the timber market in northern Sweden, and also a large business globally with offices in over 100 countries. The purpose of the study was to find out how timber suppliers want feedback/follow-up after completion of timber business. To determine this, a questionnaire survey was sent out to 75 landowners who supplied the wood for the company during the past year. The questionnaire consisted of a total of 15 questions with the opportunity to comment on certain issues.

Derome Skog AB is a purchase company whose main task is to provide Derome Timber's sawmills in Halland with timber raw material. Because of the very hard competition in the roundwood market it is important to know what kind of purchase offers are required in order to buy a valuable product from forest owners.This study aims to elucidate the crucial factors when private forest owners choose to harvest and sell their forest. As base for this study, a questionnaire has been performed with private forest owners. The result of the study shows that it is not particularly often that the timber price is the crucial factor why the forest owners choose to harvest and sell the forest products; i.e. timber, pulpwood as well as energy assortments.

There are many factors in a building project that has to collaborate with one another in order to reach the desired end result, how you work with moisture issues in timber is a very important one. While constructing Varbergs Hospital, the building company Skanska came in contact with the issue of extra high demands on the moisture content in timber. What they requested from us was a moisture program in which you clearly could follow the routines regarding work with moisture in timber. The aim is to use this program as a help during the work, in order to achieve a good result.We have developed this study in addition to the moisture program. The aim is that this study will give you a deeper understanding of the important factors to consider.

The purpose of this report is to illustrate potentials and problems with withdrawal of quality timber of birch. The purpose is also to describe possible ways to increase available quantities of quality timber. Former research is reviewed as introduction. The study begins with a prognosis of future volumes of birch timber based on consequence analyze by Swedish Forestry Agency. To illustrate the importance of active maintenance, two stands are estimated and simulated in the Heureka module StandWise.

This thesis is about the effects of fertilizing and thinning on furniture timber from redwood. Interviews of furniture manufactures have been made and observing of timber from the Swedish fertilizing and thinning trails. The result from the interviews showed which properties that is important for the furniture manufactures and then the result from the observation showed which type of management of the forest that gave the most timber that had those properties. .

This thesis is based on a market survey sent to the passive members of Södra skogsägarna within the scope of practice of Vimmerby. A member of Södra skogsägarna is considered passive if the member not has delivered timber to the association during the past five years. The purpose of this thesis was to obtain as much information as possible about the forest owners, to be able to interpret why the member did not choose to deliver their timber to the association. The survey was worked out in close collaboration with Södra skogsägarna to answer this question. The responses indicate that economic returns are important to the individual landowner. The price of timber is most important in a timber business and the majority of forest owners want to have a personal meeting if you can choose how you wish to be contacted by the inspector.

Millions of preselected progeny have been born since the development of The Beltsville Sperm Sexing Technology 1986. The method is based on flow cytometry and sorting is done on the basis of DNA difference of the X- and Y-chromosomes. Preselection of progeny provides an opportunity to obtain genetic gain and increased production as well as increased animal welfare and decreased environmental impact. However, the method is associated with low fertility, high costs and uncertainty whether the sorting process contributes to DNA damage and thereby results in genetically impaired progeny. Today, sex sorted sperm is only commercially available in the bovine industry, due to the fact that bull sperm is more suitable for selection than sperm from other species.