Systematization of Factors Affecting the Cracking of Larch Lumber during Wood Drying

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UDС

674.047

DOI:

10.17238/issn0536-1036.2018.3.127

Abstract

Cracks of various types are the most common drying defects in larch lumber. Numerous studies have shown that this type of defects depends on many factors. Therefore, the systematization of these factors will allow establishing their level of significance. The studies have also demonstrated that the main factors influencing the formation of cracks in larch lumber during drying can be divided into three groups, which to some extent depend on the wood structure. The first (main) group is associated with the presence of a significant number of woodrays in larch wood. In mixed sawn timber, they act as stress concentrators, which leads to cracks appearance during drying. Woodrays strengthen the board design in radially sawn timber. As a result, the possibility of cracks in this group of lumber decreases manyfold. The effect of the second and third groups of factors is due to the distribution of bound moisture over a cross section of the board. The goal of research is to systematize the factors that will help to construct the technological process of larch lumber drying in such a way as to minimize the likelihood of cracks appearance.

Authors

Sh. G. Zaripov, Doctor of Engineering Sciences, Associate Professor 

Affiliation

Branch of Siberian State Aerospace University named after academician M.F. Reshetnev, ul. Pobedy, 29, Lesosibirsk, Krosnoyarsk Region, 662543, Russian Federation; e-mail: zaripov_sh@mail.ru

Keywords

crack, larch lumber, hardness, woodray, distribution of bound moisture

For citation

Zaripov Sh.G. Systematization of Factors Affecting the Cracking of Larch Lumber during Wood Drying. Lesnoy zhurnal [Forestry journal], 2018, no. 3, pp. 127–136. DOI: 10.17238/issn0536-1036.2018.3.127

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Received on December 23, 2017