Search for dissertations about: "Spiral grain angle"

Showing result 1 - 5 of 10 swedish dissertations containing the words Spiral grain angle.

  2. 1. Spiral Grain in Norway Spruce

    Author : Harald Säll; Thomas Thörnqvist; Rolf Birkeland; Växjö universitet; []
    Keywords : Spiral grain angle; drying deformation; warp; wood quality; Norway spruce; Picea abies; FORESTRY; AGRICULTURAL SCIENCES and LANDSCAPE PLANNING; SKOGS- och JORDBRUKSVETENSKAP samt LANDSKAPSPLANERING;

    Abstract : Wood is a major construction material that is used in many contexts, and for different purposes. Serious problems may arise, however, when moisture related deformations as twist occur in wood used in different types of building structures, joinery and furniture. READ MORE

  4. 2. Non-destructive measurement of spiral grain with computed tomography

    Author : Paul Sepulveda; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Träteknik; Wood Technology;

    Abstract : Spiral grain is a wood feature that is formed in the living tree. Timbers sawn from trees with severe spiral grain have a great tendency to twist when the moisture content changes. This is a big problem in the wood products manufacturing process. READ MORE

  5. 3. Electromagnetic Modelling for the Estimation of Wood Parameters

    Author : Therese Sjödén; Sven Nordebo; Börje Nilsson; Andreas Fhager; Växjö universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cramér Rao bound; electromagnetic modelling; estimation; grain angle; microwave; wood properties.; Cramér Rao-gräns; elektromagnetisk modellering; estimering; fibervinkel; mikrovågor; träegenskaper.; Engineering physics; Teknisk fysik; Physics; Fysik;

    Abstract : Spiral grain in trees causes trouble to the wood industry, since boards sawn from trees with large grain angle have severe problems with form stability. Measurements of the grain angle under bark enable the optimisation of the refining process. READ MORE

  6. 4. Moisture-induced Distortion in Norway Spruce Timber - Experiments and Models

    Author : MARIE JOHANSSON; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spiral grain angle; bow; spring; twist; wood; longitudinal shrinkage; crook; warp; compression wood; lumber;

    Abstract : Timber is a natural material that is environmentally friendly, renewable, light, strong and, in the eyes of most people, beautiful. Timber does, however, have one important drawback when it is used in a modern mechanised building process - its lack of straightness. READ MORE

  7. 5. Moisture-induced distortion in timber structures - examples based on partition walls

    Author : Magnus Bäckström; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gypsum wallboard; spiral grain angle; restraint; Norway spruce; Connection; twist; spring;

    Abstract : The shape of timber changes due to variations in moisture content (MC). In Scandinavia, producers normally dry timber to an MC of 18%. However, after the studs are built into the wall structure, for example, they may become distorted as a result of further drying in the structure. The final MC in a heated building in Scandinavia is about 8%. READ MORE