Birch density: calculation of hardness coefficient

Birch is a tree actively used in the furniture industry. The secret of popularity of such material is not even in the technical characteristics of the breed, but in appearance and absolute ecology.

Application area

Birch in the design of furniture is used due to its technical characteristics:

• Wood can be easily processed;

• When cutting or other machining, it does not break off;

• In the steamed state it bends well.

Internal finishing work in the house often does not do without the use of wood. The density of birch makes it possible to use it in carpentry of various types. Taking as a material an array of birch trees, it is easy to simulate the finish in the house with panels that visually resemble a tree of expensive rock.

Features of wood

Birch has long been dubbed the tree of life. In Russia believed that this is a pure and innocent creature, personifying the soul of a young girl who, according to legend, turned into a blond, graceful birch tree.

The name of the tree comes from the Indo-European "ber", which means "bright" or "clear". Birch (from the Latin Bétula) is a genus of blond trees belonging to the Birch family. In our region refers to the breed with the highest diversity of species and forms, the density of plantations. That is why representatives of the forest industry publish different indicators of the value of tree species, depending on the region where the birch is spread. In general, there are about one hundred species of birch trees in the world.

Characteristics of wood

The texture of the tree is layered, with thin curls, often with dark stripes, with a wide color range: from ivory to a gray-red hue. The wood is homogeneous, without inclusions of natural resins. Physico-mechanical characteristics at the highest level. Birch is distinguished by a high level of strength under mechanical loads - impacts and damages.

Birch is referred to rocks with an average density of wood. The density of birch, as well as of other rocks, is determined by a special Brinell scale. According to a specially developed table, the hardness level of wood is marked by a score of 3.5 points.

The norm of natural birch moisture and the density of the material

The density of wood is determined by the special aforementioned scale. рассчитываются по формуле, благодаря которой можно вычислить влажность древесины и сравнить ее с нормой. Points, drawn according to the data from the Brinell table, are calculated by the formula, due to which it is possible to calculate the moisture content of the wood and compare it with the norm.

The scheme for determining the Brinell density consists in the use of a steel tempered ball, whose diameter is only 10 millimeters. It is pushed into the surface of the sample for examination, attaching to it a force of 100 kg. After this, the formed well is measured. коэффициент , полученный в результате отчислений, и является показателем плотности. The hardness value is calculated by a special formula, and the coefficient obtained as a result of the deductions is also an indicator of the density. он выше, тем больше плотность березы . The higher it is, the greater the density of the birch . It is important to consider that this indicator can vary.

влажности (12%) близка к буку и даже дубу, что делает эту древесину более востребованным материалом для производства мебели, чем сосновые, распространение которых куда выше, но плотность древесины в разы ниже. The density of natural birch (12%) is close to beech and even oak, which makes this wood more demanded for furniture production than pine, which is much higher, but the density of wood is several times lower.

Humidity is the first factor affecting density. In order to compare the hardness values of different types of wood, the values result in a single moisture index of 12%. Density and strength characteristics are closely related to each other. выше первый показатель, тем прочнее дерево. The higher the first indicator, the stronger the tree.

в мебельной промышленности железная береза с естественной влажностью имеет твердость в пределах 750 кг/м3 - это дерево с высокой плотностью материала. The iron birch used in the furniture industry with natural moisture has a hardness of 750 kg / m3 - a tree with a high density of material.

How to determine the density of dry or damp birch?

Raw wood is considered a moisture percentage of which exceeds 23%. This indicator is influenced by the time of the tree trimming, as well as the conditions for its further storage. To calculate the density of wet birch, such data will be required: the mass and volume of a tree with a specified humidity. The density of raw birch is calculated by the formula ρ _W = m _W / V _W , where _W is the specified moisture content of the wood.

The density of the material sharply increases under conditions of further moistening.

The moisture content of dry wood is zero. The density of birch is easy to calculate by the formula, in which the mass is correlated with its volume: ρ ₀ = m ₀ / V ₀

The density index of such a rock will be lower, since the cell cavity, as well as the intercellular space of the wood, is filled with oxygen bubbles. The porous structure is less resistant to mechanical damage.

The tree enters the market in the form of a round timber, lumber, veneer, plywood. The density of the birch, depending on its moisture content, is an important technical characteristic with which you should be acquainted. After all, on this basis, the field of application of the material is determined.