| Abstrakt: |
Recently, the woodworking industry is increasingly paying attention to the effective use of wood in the production of consumer goods. The key point in resolving this issue was and remains the careful and economical use of harvested wood. Logging volumes in Russia, according to analysts of the timber industry complex, have declined everywhere by 2017, while in the North-West region they have reached 3%. One of the possible and promising areas for the effective use of wood is gluing. Glued wood is widely used in various industries, as it has a number of unique properties in comparison with solid wood due to its dimensional stability, strength, reliability and durability. The effectiveness of gluing wood can be achieved by gluing wood with a high initial surface roughness, due to the reduction of allowances for mechanical processing of wood blanks before gluing. Existing technologies for gluing wood provide for preliminary preparation of the wood surface before gluing, due to removal of allowances for planing and milling, in order to level their surface and reduce its roughness to 200 microns or less. The exclusion of these operations from the technological process will lead to a reduction in the consumption of wood by an average of 20% of the nominal size of the workpiece and, as a consequence, will reduce the consumption of materials and energy intensity of the technological process. This article proposes using compaction as one of the possible methods for preparing the wood surface for gluing with high initial roughness, without first milling their surface. This method is based on the elastic-plastic properties of the wood material and is directly related to the deformation of the irregularities present on their surface and the magnitude of the applied load. Considering the problem of contacting wood surfaces, the authors experimentally proved that during pressing, glued wood surfaces initially had a small actual contact area, but as the pressure increased, the contact area of the mating surfaces increased due to the deformation of the tips of the protrusions on the wood surface. After deformation of all irregularities on the surface of the wood, the contact area of the blanks reached its maximum, and a further increase in the pressing pressure led to the destruction of the wood. The paper presents the results of research on this issue with a description of the research methodology. The pressures of pressure and the degree of contact of the mating wood surfaces are determined. The obtained experimental data and dependences are processed by standard statistical means. [ABSTRACT FROM AUTHOR] |
