Wood pine kernel, shiny, resinous. The kernel is brown-red, formed at 30-35 years. In a growing tree, the kernel performs mainly a mechanical role, giving the trunk necessary sustainability.

Therefore, a tree affected by the core rot, looks in healthy, but loses marketability. Swamp is wide, yellowish - or reddish-white. Sevective layers are clear. Smith strokes, in the form of thin channels, numerous, scattered by one by one or pairwise. Occupy in volume 0.1-0.7% of the volume of wood.

Core rays with a height of 0.5 mm, denser of surrounding wood. 1 cm 2 tangental cuts are more than 3 thousand. They serve to transfer and storing nutrients.

Conducting and mechanical functions in pine are performed by tracheids (90-95% of the total volume of wood). The width of the tracheid is 0.04 mm, and the length is 4-5 mm. The trees of the highest development classes (positive) form larger tracheids than trees who have retired in growth.

According to the density of the density, pine wood is divided into a condam (ore) and mandal. The first is yellowish-red, small-layer and dense. The second is white, coarse, with a thick layer of crook, low resinity and looseness. Conductive is formed in trees growing in the mountains or high boron places, mandal - in trees growing on low, sandy locations or on looglinka and chernozem-shaped spoes. By appearance On munch of wood looks like a siberian cedar wood. It is a little alone. Although Siberian cedar on physical and mechanical properties occupies an intermediate position between the fir of the Siberian and Fir Siberian, the feature of cedar wood is its light and smooth carving in different directions. For the beautiful texture of the cedar wood is used in carpentry-furniture production.

The volume of the bark of pine, protecting the tree from external conditions, is 10-17% of the volume of the barrel in the cortex. The vegetable origin of the wood causes greater variability of its properties. The volumetric weight of the pine wood depends on the conditions of location. So, in the Arkhangelsk region in a mossy bore, it is 0.50-0.55 g / cm 3; In the Moscow region - 0.59-0.62, and: in Yakutia - 0.41 g / cm 3.

Pine wood has high strength. The tensile strength along the fibers is 439 g / cm 2, with static bending - 793 kg / cm 2, the hardness is 200 kg / cm 2 (center of the European part of the USSR).

The Wood Northern Pine Wood enjoys special world fame. Its annual layers are characterized by a high content of later thick-walled tracheid in all types of forest, with the exception of the marsh. The physico-mechanical properties of northern pine are significantly higher than the pine center of the European part of the USSR. 24-hour vegetation (for the polar) and beneficial influence Golphustrum contribute to the formation in the north of full-fledged wood pine.

It is interesting to note the greater preservation of pine wood. Thus, when excavations in Armenia, the URRI fortress, Teishebaini, the Caucasian Pine's Supreme Fortress broke around 2700 years and had the following indicators: volume weight - 0.38 g / cm 3, the strength of compression along the fibers - 200 kgf / cm 2, with static bending - 223 kgf / cm 2, the stroke hardness is 262 kgf / cm 2. Such preservation of wood contributed to the clay layer, which protected the log from moisturizing, created a lack of oxygen and fenced the wood from biological destroyers. Pine logs of the ancient buildings of Brest (XIII century) had an average density in an absolutely dry state of 0.35-0.37 g / cm 3.

Currently, for long-term preservation of pine wood, deep impregnation is used by a low molecular weight water-soluble synthetic resin followed by a hardening. For modification, or plasticization, pine wood is impregnated (with a humidity of 9-10%) by gaseous ammonia (3%), then a piezothermic processing is carried out (at 170 °) and seal. After processing, the tensile strength increases by almost 2 times. When modifying wood, pine is particularly subjected to changes in cellulose and lignin. Ammonia-plasticized pine wood can be used to prepare parts of machines, furniture, musical instruments, crucial mines, wiring products, solid sawdust plates, parquet, etc. To obtain lamella (parquet slats), the pine wood is soaked with SBS-11 resin, as well as resin Based on styrene - after modification, wood acquires a light golden shade and shine. The dynamics of swelling slows down several times.

The increase in the annual layer of wood of pine ordinary is accompanied by a change in the biological composition of the tissues of young shoots. At the beginning of the active development of Cambia, protein contains up to 22.7% of the absolutely dry weight of the tissues. Upon completion of the development, the protein content is reduced to a minimum. Also there is a decrease in starch from 15.5% to 5.2% and amylase. But monomation is accumulated, sugars (up to 14.7%), which are further spent on the construction of secondary tissues.

In the xylem juice of oppressed pines, an increased concentration of monomosis, oligosachares and amino acids compared with normally developed pines was noted. In tissues of such pines, the processes of the biosynthesis of polymer compounds needed to build new cellular structures are also weakened.

As a result of air pollution with sulfur anhydride, the annual rings of wood pine are distinguished by a weak increase and deformation. First of all, the parenchymal cells of the cortex die. The stronger smalleriness leads to the deformation and destruction of the Luba, Cambia, core rays and resin strokes.

Pine wood is used to produce plywood, as a raw material in the pulp and paper industry (technological segregation), it occupies one of the main places in the country's forest exports (exported in the form of lumber, slippers, prots, etc.). In the early period of the aircraft - and pine planosity was one of the main materials.

It is interesting to note that at the Faculty of Faculty of Faculty of the National University of Australia in Canberre for decorative decorations in decorative purposes, a beech wood from England, Eucalyptus and Acacia from Australia, American Walnut from America, Red Tree from Canada, Alpine Elm, from America, New Zealand Wood, And the audience of the second floor is finished with a pine from California.

Soft, pinkish wood cedar Siberian, beautiful texture, goes on the shell of pencils, musical instruments, furniture, on battery veneer. In the cedar container (dishes), the milk does not raise for a long time, mole, ticks and mosquitoes are scared from cedar, moths and mosquitoes are scared with essential smells, bees best feel in cedar horses.

Interestingly, with age in the wood, the content of pinen increases and the amount of one of the monoterpenions is decreased - the most toxic component of the protective tree system.

Firewood pines are used to burn coal. A 670 kg of coal is obtained from 10 m 3 of wood, and with a baked - 875 kg.

In the production of green tea Kok-cha (India), the furnace of furnaces for heating and drying the leaves is made only by pine branches.

The structure of the structure of the physico-mechanical properties of wood and its biostostility was studied by many researchers: D. A. Belenkov, I. A. Alekseev, S. F. Negutsky, I. A. Petrenko, R. S. Stepanov, and others. Of great interest are work Swedish woods Heningson and Meson.

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In total, there are 325 million hectares of pine plantations in the world. Of these, almost a third is in Russia. The most common variety used as a building material is an ordinary pine, which grows mainly in Siberia and most of the European taiga.

Pine is very undemanding to the soil, so it can grow both in sandy soils and rocky mountains. Untissance and good adaptability to various climatic zones and soils contributed to the widespread range. The overall trait of all pine breeds is the demand for light. Therefore, in dense landings, they are very high with the crown at the very top.

The average pine height is about 30 meters, but separate copies reach a maximum height of 50 meters. Growth rate of 25 centimeters per year, and with age, this speed increases.

Tree growth peak falls for a period of 15 to 30 years. The maximum pine height reaches the 70 years. The thickness of the trunk in a particularly large instance can be about a meter. Pine is growing from a hundred to three hundred years. Siberian cedar variety can live up to a thousand years. The age of cutting 90-100 years and depends on many indicators, such as the density of plantations and woodity of wood.

Benefits of pine sawn timber

Pine ordinary is extremely popular building material Thanks:

• resistance to rotting and cracking;
• resistance to pests due to the ghiviths giving that the most unique smell;
• dimensions and low batchness of the lower part of the barrel, which allow producing almost the entire possible sorting of sawn timber from pine;
• high strength, especially with static bending (hardness of 200 kg / sq. Cm.);
• excellent thermal insulation properties and soundproof;
• high density ~ 513 kg / m 3, and in a freshly powerful state ~ 625 kg / m 3

A special value has wood growing in the northern regions. Physical and mechanical characteristics of northern pine are significantly higher than the characteristics of the tree from the center of the European part. This is due to a round-the-clock vegetation in the polar day and the influence of the warm mass of the Gulf Stream.

Application area

Pine wood is used everywhere. From it produce:

• phaneur;
• wood chipboard;
• bar;
• edged and non-edged board;
• rounded log for the manufacture of baths of baths and cottages;
• technological chip used in pulp and paper production;
• lining for external and interior decoration premises;
• healing board and other materials.

Did you know that Pine was standing at the sources of aircraft construction? Thanks to the availability, lightness and stock of the strength of the wood, the first aircraft built exactly from it.

Lumber are divided into six varieties:

• The board of the highest grade is used in car market and shipbuilding.
• The board 1 and 2 of the variety is used in the manufacture of joinery, gender devices, for the manufacture of beams and glued products. The board 1 and 2 of the variety is well processed and grouhed, therefore it is used in the manufacture of furniture.
• The 3 grade board is laid ceilings and walls under the stucco with individual construction.
• The 4 grade board is based on the manufacture of the supporting structures, fences, fences, roof crates, shield partitions.
• 5 grade board is used to make a package package, cargo pallets.

Improving wood properties or plasticization

For long-term conservation of wood properties, deep impregnation with low molecular weight resin, followed by its curing. This process is called plasticization. Thanks to this technology, wood hardness increases at least twice without losing other properties.

Plasticized pine is used for manufacture:

• parts in mechanical engineering and electrical engineering;
• musical instruments;
• solid sawdust plates
• lamella for parquet.

Properties of pine and its prevalence in the world, over the centuries were appreciated by humanity. Still pine wood is one of materials availableWidely used in housing construction not only due to its physicomechanical properties, but also to environmental purity, as well as a favorable effect on the human body.

Physical properties of wood and pine bark

In Russian history with a pine, one curious case is associated. At the beginning of the XVIII century on Vasilyevsky Island on the Neva was a thick pine forest. Peter I saw a pine tree in this forest, whose side bitter curved and grown into the trunk. The king ordered to cut the amazing tree - it became the first exhibit of the Kunstkamera established by him, the Museum Dikhany.

Color is the most important property of wood, determined by three factors: color tone, cleanliness and sletty material. Color tone is a wavelength of pure spectral color. For sound wood, it is equal to 581.1 nm, whereas for the Croke - 579.0 nm. The purity of the color of the sound wood is 51.6%, and the crooked part - 47.0%. Svetlota (or reflection coefficient) Wood of the sound part - 49.0%, Crooked part - 68.6%. Pine swolm after hitting river water sometimes acquires yellow color. Pine wood has a beautiful texture resulting from cutting anatomical elements. The expressive drawing is due to differences in the color of the early and late wood and the presence of the circle and the kernel. Ultraviolet radiation causes a glow - luminescence of some substances. This indicator is called the luminescence intensity (brightness coefficient), the pine wood is 17%.

Macrotructure. Pine is a breed with a sharp difference in the structure of the early and late zones of annual wood layers. The early zone of the annual layer is bright and significantly less dense than the dark, late, zone. That is why pine belongs to breeds with low equalination. The number of annual layers in trees growing in the north of the European part of Russia, in 1 cm may vary from 4 to 11.8, and this indicator depends on the composition of soil and humidity. Wood with a large number of one-year layers in 1 cm will have greater density, and hence higher strength properties compared with wood with a smaller number of annual layers. Among the pines growing in the north of the European part of the country, trees with late wood 26%. For comparison: in Western Siberia, these indicators 6.9 and 29%, respectively, in Eastern Siberia - 11.2 and 27%, respectively. In pine, growing in the Leningrad region, the average annual moisture of sorrow is 112%, and the humidity of the kernel is 33%. Humidity of pine bark in freshly dredged state 120%.

Wood pine has anisotropic properties (unequal in different directions). So, for example, in the tangential direction, wood is subject to drying of 1.5-2 times greater than in radial. The tangential destruction of the late and early zeal zabol is 9.2 and 5.5%, respectively. And the destruction of late and early zeal zones in the same direction is 8.5%. Ceffs of dermole and swelling for pine wood make up: in volume - 0.44 and 0.51%; At the radial direction - 0.17 and 0.18%, according to tangential - 0.28 and 0.31%, respectively.

Pines wood has adsorption properties. In addition to adsorption in cell wall microcapillars, water steam condensation occurs. The sorption capacity of pine wood is more pronounced in hemicellulose contained in its composition, weaker - in cellulose, even weaker in Lignin. The maximum moisture content of pine wood during water absorption is 185%.

The average density of the wood substance in an absolutely dry state in the pine swallow - 540 kg / m 3, and the kernel wood - 620 kg / m 3. The average density of wood substance at a moisture content of 12% is 505 kg / m 3. The average density of the wood substance in an absolutely dry state is 480 kg / m 3. The basic density of pine wood - 415 kg / m 3.

Pine belongs to breeds with low wood density. For comparison: the middle density breed (550-740 kg / m 3) - larch, tees, birch, etc.; Breeds with high wood density (more than 750 kg / m 3) - White acacia, oak chesttopalistic, pistachio and male. The permeability of wood for gases in the radial direction is greater than in a tangential, 2-5 times. The nucleus pine has a very low breathability, 10-15 times smaller than in Collus.

Thermal and acoustic properties of pine wood

The thermal conductivity of pine wood in the tangential direction is 0.53 W / (M.ºС). In the radial direction, this indicator is somewhat less. When heated wood expands. Due to anisotropy, the expansion in different directions will be different. The smallest coefficient of linear expansion in the direction along the fibers (α "||) is 4.2 × 10-6 1 / ºС. The average linear extension coefficient in the radial direction (α" R) is 15.0 × 10-6 1 / ° C . The largest linear expansion coefficient in the tangential direction (α "t) is 29.0 × 10-6 1 / ° C.

Dry pine wood has very low electrical conductivity. The specific volumetric resistance of wood in a completely dry state is 2.3 × 1015 Ohm ∙ cm across the fibers and 1.8 × 1015 Ohm ∙ cm - along the fibers.

Wood ability to reflect and conduct sound is called acoustic resistance. In the case of indoor-dry wood along the fiber it is 2.8 × 103 PAs / m. For comparison: the acoustic resistance of the larch wood is 3.3 × 103 PAs / m, air - 429 pa ∙ s / m, and steel - 395 × 105 PAs / m. The speed of sound propagation in indoor-dry pine wood with longitudinal oscillations is 5360 m / s. The sound absorption coefficient of a pine partition with a thickness of 19 mm in the frequency range from 100 to 4000 Hz is in the range of 0.081-0,110.

Mechanical properties of wood pine

The strength of the pine wood with compression along the fibers with a moisture content of 12% (normal) is 46 MPa, and at 30% or more - 21 MPa (see table). For comparison: the tensile strength of larch - 62 and 25%, poplar - 40 and 17%, respectively.

Pine belongs to the group of rocks with soft wood. Late wood (105.4 MPa) hardness is significantly higher than that of the early (20.6 MPa). The shock hardness of pine wood at a moisture content of 12% is 0.72 J / cm 2, with a moisture content of wood 30% and above - 0.55 J / cm 2.

Wear resistance of pine wood, or the ability to resist the gradual destruction of its surface zones by friction from the effects of abrasive elements or micronetherities of a more solid body in transverse, radial and tangential directions, is: 0.12, 0.31 and 0.28 mm, respectively.

The ability of wood to hold fastenings directly depends on the density. Thus, the resistance to pulling the nail or scouring of the timber (density of 730 kg / m 3) requires an effort about four times large than in the case of pine wood (density of 440 kg / m 3).

Wood pine has a small ability to begib, it is bad. Resistance to splitting is relatively small and amounts to normal humidity (12%) in radial and tangential planes 11.5 and 11.3 N / mm, respectively. With a humidity of 30% and above, this indicator drops to 7.2 and 7.1 N / mm in radial and tangential planes, respectively.

Properties of pine wood in comility and vertex parts of unequal. For example, the density decreases in the bottom upward direction and increases from the center to the peripheral part for both the sound and for the christ area of \u200b\u200bthe wood. The width of the annual rings is closely related to the physico-mechanical properties of wood. The greater the one-year rings in one centimeter (their number may vary from 3 to 25, depending on the conditions of growth), the higher the strength properties of wood.

Characteristics of pine wood allow you to create products or structures of high strength and stiffness at a small mass. For example, in transport engineering, air and shipbuilding, construction and production of some musical instruments.

The main area of \u200b\u200bapplication of pine wood is the manufacture of sawmills. Other things being equal the most important condition Receiving high-quality sawn timber are drying modes. The more intense the drying process, the higher the residual tension in the wood. Thus, after the atmospheric drying of pine sawn lumber, compressing stresses in surface areas do not exceed 0.5 MPa, and 0.2 MPa stretching in the inner zone. After chamber drying, the voltage in the surface and internal zones of pine sorties can reach up to 4.4 and 1.7 MPa, respectively.

Clades

For the production of a number of substances in the industry, products produced by excretory or secretory systems of pine are used. Cuts, applied at the bottom of the tree trunk, open the smallest anatomical structures: moves, cavities containing these products. Under the influence of internal pressure, they go to the surface of the trunk, and they are collected in a liquid or hardened form. The product products can be divided into two types: terpenoid compounds and a substance of a carbohydrate group. Carbohydrate products - polysaccharide gums and sugar juices - find industrial application in food production. The most valuable part of the rod products form terpenoid allocations. Among them are latex, guttapercha and resins, essential oils, alcohols, aldehydes, ketones, etc. When processing gils on the rope-terrent plants, the main types of products are obtained: turpentine and rosephole. Skipidar as a solvent is used in the production of oil and artistic paints, varnishes, waks, mastic, for medical purposes. When separating the turbidard, the fractions are obtained by camphor, thermal hydrate, products for the perfumery industry, raw materials for the synthesis of polyester fibers - Lavsana, Terenel. Rosin is used as an additive to rubber to give it elasticity and frost resistance, for the synthesis of rubber, in the production of herbicides and flopagaters. In addition, it is the basis for leatherette, emulsifiers, plastic masses, insulating materials for wires, rubber for automotive tires, varnishes, paints.

IN therapeutic purposes Pine kidneys are used, cheva, as well as a province that has many healing properties. For example, an antimicrobial effect has an antimicrobial effect. The processing products of the turpidar and rosifoli are Creilin, various medical ointments, vitamins A and E. Pine kidneys (young shoots at the very beginning of growth), which contain resin, vitamin C, essential oil, tannilic, mineral salts, collected from October to May. The decoction of pine kidneys has an expectorant, diuretic, disinfecting effect. It is used for inhalations and rinsing in inflammatory diseases of the upper respiratory tract. From fresh pine conifer In the spring prepare a vitamin decoction. It is also added to the baths appointed with nervous disorders and diseases of the cardiovascular system.

Anton Kuznetsov, teacher SPGLTU

It is difficult to call any sector of the national economy, where wood would not be used in one form or another, and list products in which wood is not an integral part. In terms of use and variety of use in the national economy, no other material can be compared with it. Wood is used for the manufacture of furniture, joinery and construction products. It makes elements of bridges, ships, bodies, cars, containers, sleepers, sports equipment, musical instruments, matches, pencils, paper, bodies, toys, souvenirs. Natural or modified wood is used in mechanical engineering and mining industries; It is the raw material for the pulp and paper industry, the production of wood plates.

Wood is a product of plant origin, on a chemical composition, which is a complex complex consisting mainly organic substances of various composition and structure. The most significant for the characteristics of plant raw materials is cellulose, hemicellulose and lignin, the content of extractive substances, dummy acids, ash components, as well as the carbohydrate composition of hydrolyzates formed during quantitative hydrolysis of easily and hard-folmic polysaccharides and other substances, is essential.

Determination of these components and leads to the most complete characteristic. chemical composition vegetable tissue.

Recently, coniferous wood breeds have been widely used in forestry and wood processing industries, the study of their chemical composition, structure and morphological features plays an important role in the right and rational use Wood breeds.

1. Analytical Overview

Pine (Pinusl.) - evergreen tree From the pine family (Pinuseaelindl). Currently there are about a hundred species relating to this kind, of which fourteen grows in Russia and about the ninety was introduced, the subspecies of some pines are listed in the Red Book. The most common view of a pine growing in Russia is an ordinary pine.

In the territory Russian Federation Naturally, more than 50 types of pine are growing and cultivated.
In construction, mainly pine following species: Ordinary, flexible, resinous, marsh, Korean.
And in the northern and middle latitudes the most common type is the pine (Pinus Sylvestris L). However, the quality of the wood of pine ordinary depends on the place of growing tree.

The best material for construction, which has excellent physicomechanical properties is pine, growing in the northern lane - Angarskaya, Karelian, Arkhangelsk.

This is due to the fact that in the north winter is longer, cold, and the summer is short and dry, which makes the distance between the annual rings minimal (no more than 2 mm). And pine out middle strip It has wider rings (up to 10 mm) due to a warmer, wet and long summer, soft winter. Thicker annual rings in pine attachd wood looseness, and therefore, the log will have lower indicators for strength, heat capacity and higher cracking and greater shrinkage percentage

For example: the percentage of shrinkage of the Arkhangelsk log is 3-4%; Kirovsky, Vologda log - 4-6%; Kostromsky 6-7%; Tver, Smolensky, Yaroslavsky - up to 10%. Therefore, when choosing a material for the construction of a house, you must consider all these moments.

Depending on the place and conditions of growth of wood, the core of pine (the central part of the barrel) can have a different color. On the more elevated, dry and low-alcoholic soils in pine, fine-layer dense wood is formed, called Kondova, which is especially valued in construction. Conductive pine has meat-red or yellow-red core. Frue, well-humidized soils are formed a large, less dense, medane wood having a core of pale yellowish color. Mandal pine is valued less and has the worst mechanical properties.

Specifications Pines

Data at 12% humidity; 1 MPa \u003d 1 N / mm2

Comparative characteristics Woods coniferous rocks.

Description of the main coniferous wood

PINE

The breed and its basic properties - the wood of medium density, sufficiently high strength, resistant against rotting and damage to the fungus, is well processed. It is especially valued in construction due to the small number of bitch and a small change in the diameter along the length of the trunk.

External signs are a none breed with resin moves (focused mainly in late wood). Swamp is wide from yellowish to pink colour. Sevective layers are clearly visible on all cuts with a clear boundary between early and late wood. The core rays are not visible.

SPRUCE

The breed and its basic properties - in physical and mechanical properties (density, hardness, compression strength along the fibers and static bending) is inferior to a pine (about 10%), but in terms of the quality ratio, it exceeds it by 3-4%. Wood is harder to be processed due to the abundance of bitch and their high hardness. Advantages: one-sidedness of the structure, long fibers, stable white color, low resinity, high ability to resonate.

External signs - the breed of non-unomedic, peelless, has a few smallest moves. Uniform wood white colorSometimes with a weak yellowish or pink tint. Sevective layers are clearly visible at all cuts; Late wood is somewhat different from the earlier more dark color. The core rays are not visible. Unlike pine, there are larger swirls located by the mutuals, between which single bits of smaller sizes come across.

LARCH

Breed and its basic properties - wood, being dried, weakly susceptible to rot; Well, opposes the action of water.

External signs - one-time layers are clearly visible at all cuts. The larch barrel is 70% consists of a kernel, dramatically released by properties and color. The sound part of the wood contains the bulk of substances that give larch increased resistance. Dark. The cloth has a narrow larch, 8-20 mm, 25-30% of the wood mass. Light. In physical and mechanical properties is inferior to the kernel

FIR siberian

The breed and its basic properties are wood with noticeably reduced physicomechanical properties compared to Wood fir. Construction is practically not used.

External signs - the breed of infantry, with ripe wood; It looks like a fir wood, which is distinguished by the absence of resin moves; Uniform white color. Sevective layers are visible at all cuts; Late wood is different from an early darker color. Large bitches are arranged by mutters, between which are small single beds.

Cedar (pine cedar)

The breed and its basic properties of wood soft, easy, easily processed. In physical and mechanical properties, it occupies an intermediate position between the wood ate and fir, but exceeds them in resistance to rotting. Compressive strength and static bending below 4-5% at density equal to the density of fir wood

Exterior signs - wood has a core of light and yellowish-pink color, is not sharply deliberate from a wide yellowish-white swamp. Sevective layers are noticeable, the transition from early wood to the late gradual, rustic. Smith strokes are less than that of pine, but they are larger. The core rays are not visible.