There are a specific weight of wood (solid wood masses without voids) and the proportion of wood as a physical body. Specific gravity Woodiness is higher than the unit and little depends on the tree of the tree; On average, it is taken equal to 1.54. The proportion of wood substance is important when determining the porosity of wood. The conditional volumetric weight has before the surround weight, the advantage that it does not depend on the value of the heathene and does not require the recalculation of 15% humidity. This makes it possible to significantly simplify the calculations and provides more uniform results when determining the Γus of several samples.

Classification of breeds by density

The density values \u200b\u200bof different wood breeds differ very significantly. By the standard moisture of the breed, it is customary to divide into three groups:

- Breeds with low density (540 kg / m3 or less): from coniferous - pine, spruce (all kinds), fir (all kinds), cedar (all kinds), juniper ordinary; from deciduous - poplar (all kinds), Lipa (all kinds), Iva (all kinds), alder black and white, chestnut sowing, white, gray and manchur, velvet amursky;
- Middle density breeds (540-740 kg / m3): from coniferous - larch (all kinds), tees; from deciduous - hound, fluffy, black and yellow; Beech Eastern and European, Elm, Pear, Oak Summer, East, Swamp, Mongolian; Ilm, Karagach, Maple (all kinds), Laundry, Walnut Walnut, Platan, Ryabina, Persimma, Apple Tree, Ordinary and Manchursky;

- high density breeds (750 kg / m3 and higher): white and sand acacia and sandy, iron, Glootichia Caspian, Hickory White, Grab, Oak Chesttopoliste and Araksinsky, Iron Tree, Suskend, Pistachio, Hmelegrab.

Among the foreign rocks there are those whose wood has both very low density (BALSA - 120 kg / m3) and very high (Bakat - 1300 kg / m3).

In the tables of the state system of standard reference data (GSSD) issued by the State Standard of Russia ("Wood. Indicators of the physicomechanical properties of small samples without defects"), more detailed information on the density of the wood, indicating the type of woody rock and its growth area.
The density of the cortex is studied much less than wood. Available data is highly different.
A comparison of this data with an average wood density with standard humidity shows that the density of the pine bark is 30-35% more than wood, ate is 60-65%, and birch - by 15-20%.

Influence of wood structure on its properties

The wood density also strongly affects the water contained in it. First, it increases the sample, and secondly, the swelling of the cell walls in water causes a change in the size of the sample. Therefore, the density of wood is determined either in the absence of water, or when it is a certain mass fraction in the wood. Fully dried samples actively absorb water from ambient air and in some cases it is more convenient to handle wood samples containing a known amount of water and in relative equilibrium with the surrounding atmosphere. In technological calculations, the basis density of wood is sometimes used, representing the mass ratio of an absolutely dry sample of wood to its volume in the maximum swelling state. This condition is characteristic of freshly chopped wood and wood, which has been in contact with water. In this case, actually define the basic relative density; However, equating 1 g of the displaced water to volume 1 cm3 is converted from a dimensionless value in a value having dimension.

Wood rocks are characterized by certain values \u200b\u200bof wood density, which are affected by the growing conditions. Depending on the botanical species, the density of the wood varies widely. For example, the density of absolutely dry wood varies from 350 kg / m3 in Russia in Russia in the Siberian fir to 920 kg / m3 in the birch of iron.

On the density of wood with a moisture content of 12%, all domestic breeds are divided into three groups: with low density (540 kg / m3 and less) - spruce, fir, pine, pine cedar, poplar, Iva, Lipa, Olha; medium density (550 ... 740 kg / m3) - larch, birch, beech, oak, elm, maple, ash; high density (750 kg / m3 or more) - acacia, housing, separate species Birch, oak, ash. It should be noted that wood coniferous rocksWith the exception of larch and some types of pine, has a low density.
It is also closely associated with such a property as permeability of liquids and gases. Wood permeability characterizes its ability to pass liquid or gases under pressure, which is very important for wood processing processes. The permeability of wood is due to the existence in the wood of the system communicating through the pores of cell cavities and interclausers. The dry cell wall, as already noted, has low porosity, and its components are or included in crystalline sections, or are in a glassy state, which makes the cell wall almost impermeable for non-polar media. In the polar fluids, cell walls swell strongly and their porosity increases. For technological purposes, water permeability and gas permeability are most important. Since there is a good correlation between these characteristics, and the wood tests on gas permeability require significantly less time, then its gas permeability is often determined in practice to estimate wood permeability.

The permeability of wood, estimated by the mass or volumetric rate of passing the flow of liquid or gas through the unit of the surface of the surface of the wood sample, is maximum in the axial direction, i.e. Along the fibers. It is several times higher than that of coniferous, as it coincides with the direction of the vessels. Permeability across the fibers is significantly less and the core rays have a great influence. The formation of ripe and in particular the sound wood reduces permeability, and in individual rocks, the none wood becomes waterproof.

What density do oak, beech and other breeds

In descriptions interior doors And the breeds of trees, of which they are made, often slippages the term "wood density". Descriptions are good, but they do not give such a clear understanding, as numbers - what does it mean "a little more dense"? Values \u200b\u200bin the form of numbers give an accurate picture, on the basis of which you yourself decide which tree is most suitable for the manufacture of interroom doors.
Before moving to numbers, we define what the wood density is and for which it needs to be known.

The density of wood is called the ratio of its mass to volume. Simply put, than a cubic meter weighs more, the more denser. The density of wood, called depends on the humidity, therefore it is customary to operate with the values \u200b\u200bobtained during the humidity of 12%.

With the first question figured out, go to the second. The density of wood directly affects two important properties - strength and hygroscopicity. Dense wood has a higher strength and in most cases hygroscopicity. The last term means that the doors from high-quality wood are more dependent on moisture changes - everyone knows that the wood has to absorb moisture and expand. For this reason, the doors made of aspen, linden or pines, which are at the very bottom of the table, are used in saunas and baths, where the doors from beech just stop closing.

Values \u200b\u200bare given in grams per cubic centimeter (g / cm3) with a moisture content of 12%. Let's notify your attention that in some cases the average values \u200b\u200bare given.

Brief description of wood properties: Grab.

Grab is most widespread in Europe, Malaya Asia and Iran. Wood brilliant, heavy, viscous. Color: White-gray. Density: 750 kg / m (cubic). Bringel hardness: 3.5.

Liswood. One of the most beautiful Australian trees. The color is light brown with a characteristic graininess. Density: 910-1050 kg / m (cubic). Grainel hardness: 5.5. Paduk. With bright positive energy. Color: from light yellowish-red to dark brick-red, darkened with darker lines. Density: 850-950 kg / m (cubic). Bringel hardness: 4.2.

Wenge.Orodina Wenge Wenge Tropical Jungle West Africa, right up to Zaire. The structure of the material is large, riveting, wood decorative and at the same time severe and resistant to pressure and bending. Color: from golden brown to very dark brown with black streaks. Density: 850-900 kg / m (cubic). Bringel hardness: 4.1.

Tigerwood (tiger tree). Grows in Western Tropical Africa. Color: yellowish brown, sometimes marked with dark stripes, "veins". Density: 800-900 kg / m (cubic). Bringel hardness: 4.1.

Kokobolo. High stability when changing humidity. Color: Dark, deep red shade with black, irregular stripes. Bright, expressive, beautiful texture. Density: 800-980 kg / m (cubic). Grainel hardness: 4.35.

Rosewood. The wood is very dense and heavy, is well polished, sinking in entering. Color: Attractive light brown with purple-lilac sampling. Density: 1000 kg / m (cubic). Grainel hardness: 5.5.

Yarra. The name of one of more than 500 varieties of Australian eucalyptus. Color: All shades of red, from red-pink to dark red. Over time, Yarra darkens and its painting can acquire very diverse shades. Density: 820-850 kg / m (cubic). Bringel hardness: 5.0.

Pear. Wood is dense, firm, well processed, little cracks. Color: from yellowish and white to brownish-red. To increase the hardness, pear wood is placed in water and withstand a long time, after which they are dried long in natural conditions. After drying, it acquires a browned hue. Density: 700 kg / m (cubic). Bringel hardness: 3.4. Oak (Morny). Wood durable, durable, resistant to external influences. After a long (from 50 to 300 years), soaking (bullings) without access of oxygen, wood acquires velvet-black color. Black color.

Bearing dubbed wood material. Through thousands of years, sunken oak trunks were at the bottom of the reservoir, where without air access, in the process of the sea, the strength not inferior to the stone was acquired. Nature itself gives him strength, durability and unique color gamut. Density: 750 kg / m (cubic). Grainel hardness: 3.8. Sugit. Wood is firm as a bone, the specific weight of it is more than the specific weight of the water, sickness sinks in water. Therefore, it goes to the manufacture of details where significant rigidity is necessary. Color: light yellow, matte. Density: 1350 kg / m (cubic). Bringel hardness: over 8.0. Makasar. Type of ebenic tree common in Southeast Asia. Color: Dark brown with black streaks. It has a very beautiful texture. Density: 1000 kg / m (cubic). Bringel hardness: 7.0.

Eben. Trade is distinguished by many varieties of ebony. The most rare and expensive grows only in countries Central Africa. So expensive that payment for it goes in kilograms. The exports of African Ebena are limited and fully controlled by the governments of those countries where it is mined. Wood is very dense and heavy, sinking in water. Color: from dark brown to velvety-black with characteristic lighter (or light brown) longitudinal veins. Density: 1200 kg / m (cubic). Bringel hardness: over 8.0. Yatoba. She is also called Brazilian cherry. Wood heavy, durable, hard and at the same time amazingly elastic. It is difficult to handle, but polished and polished almost to mirror glitter. Color classification: Density: 960 kg / m (cubic). Brinel hardness: 4.8. Zebrano. Grows in Gabon and Cameroon. Wood solid and heavy. The surface is shiny, the texture is somewhat large. Color: Light golden with narrow strokes from dark brown to almost black coloring. Density: 900 kg / m (cubic). Brinell hardness: 4.5. Kevazingo. It grows from Equatorial Africa, from Cameroon and Gabon to Congo. Tree up to 35-40 meters high, the barrel diameter is up to 1.5-2 meters. Wood from red-brown to dark red. It has a beautiful pattern of texture. Tight, solid, stable. Density: 820-850 kg / m (cubic). Bringel hardness: 5.0.

Black Grab. Grown in the mountains of the Caucasus. Wood log house produced in winter when the slotting stopped. The secretion of the paint is transmitted from generation to generation. Black color. Density: 700 kg / m (cubic). Bringel hardness: 3.4. Merbau. Grows in Southeast Asia (Malaysia, Indonesia, Philippines). The main advantages of Merbau is that it contains in the pores of oily substances, is very solid, resistant to moisture and little fuses. In the course of operation, Merbau darkens, especially bright areas, as a result of which the wood color is generally levels. Color: brown, from light to dark tones, places with an impact of yellow streaks. Density: 840 kg / cubic meters. Bringel hardness: 4.1. Ash. Wood heavy, hard with high strength. Having a shock viscosity and one of the most valuable breeds in the world for the manufacture of sports equipment. Density: 700 kg / m (cubic). Brinell hardness: 4.0-4.1.

Tree density of various humidity

One of of essential factors When organizing the transport of forest is the density of wood. She happens to be an important indicator When calculating the cost of transportation and selection of forestry.

The weight of the tree is the specific and volumetric. The specific weight is the mass of the volume of the volume of the tree without taking into account the breed, moisture and other factors - is 1540 kg / m 3. The bulk weight is the mass of the volume of wood volume with moisture and rock. Based on the bulk weight, you can determine the density of the tree. The density of trees of different breeds is different. Also, a very modified density of the tree of one rock, depending on the geographical location and the type of forest.

With an increase in wood humidity, the density increases. For example, with a humidity of 15% - 0.51 t / m 3, and with a humidity of 70% - 0.72 t / m 3. According to the degrees of moisture, the tree is separated: absolutely dry (humidity - 0%, only in laboratory conditions), indoor-dry (humidity up to 10%), air - dry (humidity - 15-20%), freshly served (humidity 50-100%) , wet (over 100%, when storing wood in water).

Wood density - as a building raw materials.

Wood density - Wood mass attitude to both RW \u003d MW / VW
The density depends on the breed and humidity, usually defined on the table. All tree breeds are divided into 3 groups:
1) low-voltage P<0,5(г.см3)(сосна,ель, (пихта, кедр, осина, ольха, липа, тополь)
2) Middle Plight0.5 3) Highly dense P\u003e 0.7 (G.Сm3) (Grab)
This property is characterized by a mass of a unit of material, and has a dimension in kg / m3 or g / cm3.
a) the density of the wood substance PD, g / cm, i.e. The density of the material of the cell walls, is: PD. \u003d MD.V. / Vd.V., where MD.V. and Vd.V. - respectively mass, g, and volume, cm3, wood substance.
This indicator is equal to all breeds of 1.53 g / cm3, since the chemical composition of the cell walls of the wood is the same.
b) the density of absolutely dry wood P0 is: P0 \u003d M0 / V0, where M0, V0 is respectively the mass and volume of wood at w \u003d 0%.
The density of wood is less than the density of the wood substance, as it includes emptiness (cell cavities and intercellular spaces, filled with air).
The relative volume of cavities filled with air, characterizes the porosity of the wood P: n \u003d (V0 - Vd.V.) / V0 * 100, where V0 and Vd.V. - respectively, the volume of the sample and the wood contained in it at w \u003d 0%. The porosity of wood varies from 40 to 80%.
c) Wet wood density: PW \u003d MW / VW, where MW and VW are respectively the mass and volume of wood with moisture content of W. The density of wood depends on its humidity. With moisture, W.< Wпн плотность изменяется незначительно, а при увеличении влажности выше Wпн наблюдается значительный рост плотности древесины
d) partial moisture of wood P`W characterizes the content (mass) of dry wood in a unit of volume of wet wood: p`w \u003d M0 / VW, where M0 is a mass of absolutely dry wood, g or kg; VW - volume, cm3 or m3, wood with this humidity W.
e) the base density of the wood is expressed by the ratio of the mass of absolutely dry sample M0 to its volume with a humidity equal to or above the saturation limit of Vmax cell walls: PB \u003d M0 / Vmax. This main density indicator that does not depend on humidity is widely used to assess the quality of raw materials in the pulp and paper industry and in other cases.
The magnitude of the wood density varies in very wide limits. Among the breeds of Russia and the near abroad, wood with a very low density has a Siberian fir (345), Wapa Belaya (415), and the most dense - male (1040), the core pistachio (1100). The range of changes in the density of the wood of foreign rocks is wider: from 100-130 (bald) to 1300 (Bakat). The density values \u200b\u200bhere and below are given in kilograms per meter cubic (kg / m3).
On the density of wood at 12% of the humidity of the breed divide into 3 groups: with small (P12< 540), средней (550 < P12 < 740) и высокой (P12 > 740) Wood density.

The volumetric weight of wood depends also on the width of the one-year layer. Hardwood has a bulk weight decreases with a decrease in the width of the annual layers. The greater the average width of the annual ring, the greater the bulk weight of the same breed. This dependence is very noticeable from ringing rocks and somewhat less noticeable in scattered. In coniferous rocks, the inverse relationship is usually observed: the bulk weight increases with a decrease in the width of the annual rings, although there are exceptions to this rule.

The volumetric weight of wood decreases from the base of the barrel to the top. In middle-aged pines, this fall reaches a value of 21% (at an altitude of 12 m), the old pine comes to 27% (at a height of 18 m).

The decrease in volume weight at the height of the trunk reaches 15% (aged 60-70 years, at a height of 12 m).

Patterns in the change in the volume weight of wood in the diameter of the barrel is not observed: some breeds, the volumetric weight is slightly decreased in the direction from the center to the periphery, the others are slightly increasing.

The big difference is observed in bulk weight in early and late wood. Thus, the ratio of the volume weight of early wood by weight late at Oregon pine is 1: 3, in pine 1: 2.4, larch 1: 3. Therefore, in coniferous breeds, the volumetric weight increases with increasing the content of late wood.

Wood porosity. Under the porosity of wood, the volume of pores in percent of the total volume of absolutely dry wood is understood. Porosity depends on the volume weight of wood: the greater the bulk weight, the less porosity.

For the approximate determination of porosity, you can use the following formula:

C \u003d 100 (1-0,65γ 0)%

where C is the porosity of wood in%, γ 0 - the bulk weight of absolutely dry wood.

The table indicates the weight of 1 m3 of wood relative to the percentage of humidity.

With construction work related to the use of lumber from coniferous type trees, the correct values \u200b\u200bof the specific gravity of pine wood are very important. In contrast to other diverse building materials, this species do not have a single specific weight that somewhat complicates the selection process. The fact is that wood pine, like any wood, is a natural porous type material. Accordingly, depending on the variety of pines and from the percentage ratio of humidity and the proportion of pine is changed.

As mentioned above, the main parameters affecting the volumetric weight of the pine is humidity. For example, the highest rate of specific gravity is still untouched, growing pine. This is due to the fact that the tree requires a large humidity for growth. In this case, the humidity is simultaneously a useful substance and carrier of others, no less useful, vitamins and minerals. The amount of moisture is entirely depends on the variety of pine, the season of the workpiece and terrain. Humidity indicators of living pines can vary from 29% to 81%. The lowest indicator, respectively, dried pine, as the humidity in this state tends to zero.

Weight table 1 m3 pine depending on its humidity.

It is very difficult to determine the percentage ratio of moisture with remedies. And this is a very important indicator to determine such a parameter as the specific weight of the pine cubic meter. Usually, these procedures are held in special technological laboratories.

The easiest way, when buying a material, clarify the humidity from the manufacturer. After that, with the help of the table presented, find out the weight of the pine cube with a flag of 5% to 90% and the density of the material:

Specific and density of pine depending on humidity

Pine moisture percentage	Specific weight (kg/ m3)	Density (G./ cm3)
Standard, from 10 to 12%	500 - 505	0,5 - 0,505
1 - 5 %	480	0,48
12 %	505	0,505
15 %	510	0,51
20 %	520	0,52
25 %	540	0,54
30 %	550	0,55
40 %	590	0,59
50 %	640	0,64
60 %	680	0,68
70 %	720	0,72
78 - 90 %	750 - 820	0,75 - 0,82
80 %	760	0,76
100 %	850	0,85

Practical importance and importance.

Among the coniferous building materials is the wet, dried, dry and raw pines. However, these terms do not give a certain accurate value of humidity, so it is extremely important to know clear figures. For example, the requirements for the use of pine woven is not provided by legislative acts. But, when performing certain works, GOST establishes humidity rates, for example:

in the manufacture of structures and products intended for accommodation on the separated area, wood is used with humidity from 11 to 14%;

for the manufacture of structures and housing products, wood is used with humidity from 8 to 10%;

for parquet - Wood with humidity from 6 to 8%.

When designing a different kind of wooden structures, such an indicator is often used as the weight of those lumber, of which they are supposed to be made. It would seem that such information can be obtained from specialized directories. However, in such literature, unfortunately, only 1 m 3 of a bar is often indicated or, for example, boards. You are acquired by lumber often not by cubic meters, but simply ply.

The length of the woodworking crafts sold can be different. But most often such enterprises sell lumber to 6 m. So how, for example, there may be a weight of a natural humidity of 150x150x6000 mm? To find out if you have to do somewhat simple independent calculations.

From which the weight of sawn timber

It is clear that the more moisture is contained in the bar, the more it will be harder. However, the weight of such lumber is dependent on this factor. Performing calculations, in this case, it is necessary to take into account the characteristics of the specifically of the wood itself. After all, for example, a beam from oak in any case will be heavier lumber from birch.

What is natural humidity

So, how to perform the calculation of the weight of the wooden bar of the natural humidity of 150x150x6000 mm of one or another breed? Make such calculations are not really too difficult. However, before proceeding to calculations, it is still worth decreasing with the concept of "natural humidity".

In construction and in the manufacture of various products, used exclusively wood with humidity no more than 12-15%. And even such boards and a timber before use in most cases are additionally dried for some time.

The humidity of only sawing wood will, of course, very high. In any case, 12-15% of its indicator will exceed significantly. It is such humidity that is called natural. That is, we ultimately need to know the weight of the wooden bursa of standard length with a cross section of 15x15 cm made of freshly made wood.

Consider the breed

As a basis, when performing such an operation, you should take information from the lumber weight table in cubic meters.

Perform calculations in this case as follows:

recognize the number of bars of a given length and section in 1 m 3;

by simple division, they calculate the mass of one such unit of lumber.

In one cubic meter of a bar having a size of 150x150x6000 mm, thus will contain 1: 0.15: 0.15: 0.15: 6 \u003d 7.4 pieces. To find out the weight of the beam, in this case you need:

watch the weight of the cubic meter for this particular wood breed;

split this parameter to the number of bars in the cubic meter.

For example, with a humidity of 15% 1 m 3 pine sawn timber weighs, according to the table presented above, 440 kg. That is, the calculation in this case will look like this:

440 / 7.4 \u003d 59.5 kg.

It is easy to determine also that the weight of the bar of 150x150x6000 mm from the larch of the same humidity will be 90.5 kg. For aspen, this indicator will be 67.6 kg.

Instructions for calculating the weight of the scope of natural humidity 150x150x6000 mm

Thus, the weight of sawn timber specified humidity is not too difficult to learn. To do this, you just need to solve two simple mathematical examples. But what will be the weight of the natural humidity of 150x150x6000 mm? In order to determine this, among other things, you need to know and actually the last indicator itself for a particular wood variety.

You can also get such information from special tables. So, for example, the natural moisture content of pine is 60-100%, larch - 50-70%, birch - 70-90%. These parameters should be taken in this case to calculate the weight. Exact calculations at the same time, for obvious reasons, it will be impossible to do.

So, how much does the timing of 150x150x6000 mm of natural humidity weigh? Taking into account the data of the table presented above:

pine beams of such dimensions will weigh from 580 / 7.4 \u003d 78.3 (60%) to 730 / 7.4 \u003d 98.6 (100%) kg;

the weight of the natural humidity of 150x150x6000 mm from the larch will vary in the range from 820 / 7.4 \u003d 110.8 kg to 930 / 7.4 \u003d 125.7 kg.

Similarly, it is possible to calculate the beams of such dimensions of natural humidity for any other breed.

Specific gravity

Types of wood density differ only two:

bulk weight (density of the physical body of wood);

specific directly wood fibers).

Above, we considered a method for determining the volume weight of a bar of 150x150x6000. Natural humidity or specified with such calculations is an important indicator. Indeed, in this case, the weight depends on the amount of moisture contained in the structure. But if you wish for beams, a specific density indicator can be calculated.

You can do it using the table presented above. Calculations in this case will be carried out without moisture. That is, to calculate, you need to find the number of beams of a certain size in the cubic meter and simply split the indicator from the table to the resulting number.

Thus, for pine 520 / 7.4 \u003d 70.3 kg, this is the proportion of the bar of 150x150x6000. Natural humidity is a permissible operational or any other - in this case are not taken into account.

When organizing a cargo transportation forest, wood density is an important indicator in the selection of forestry and calculating the cost of transportation. This will help to avoid overload, which will apply from fine accordingly.

On the weight of M3 wood, the density of the material has a special value, respectively, to properly solve the issues, it is necessary to determine the density value. Distinguish two types of density: volume weight (the density of the structured physical body) and specific gravity (Density of wood substance).

Volumetric weight of wood

The weight of the cubic meter of wood depends on the tree and humidity breed.

Calculator calculating the bulk weight of the tree.

Tree Acacia White Birch Beech Vozm Oak Grab Spruce Ordinary Maple Lipa Larch Olha Walnut Walnut Fir Siberian Siberian Fir Caucasian Pine Sung Pine Cedar Poplar Casual Ovy

Volume, m3:

Specific wood

Wood material is called a mass of solid wood materials without natural voids. This type of density is measured in laboratory conditions, as it requires additional measurements, impracticable under normal conditions. For each wood of all species and tree breeds, this value is a constant and is 1540 kg / m3. However, wood has a multicellular fibrous structure of a complex type. Walls made of woody plays the role of a frame in the structure of wood. Accordingly, each breed and species of trees have cellular structures, shapes and sizes of cells vary, as a result of which the proportion of the tree will be different, as well as the weight of the M3 of the tree.

Also, moisture has a large role in changing the specific weight of the wood. Due to the structure of this material, with the increase in humidity, the wood density increases. However, this rule does not apply to the density of the wood substance.

Table of wood density of different humidity (kg / m3).

№	Breed of wood	Moisture percentage,%
		15	20	25	30	40	50	60	70	80	100	Fresh *
1	Larch	670	690	700	710	770	820	880	930	990	1100	940
2	Poplar	460	470	480	500	540	570	610	650	690	760	700
3	Beech	680	690	710	720	780	830	890	950	1000	1110	960
4	Elm	660	680	690	710	770	820	880	930	990	1100	940
5	Oak	700	720	740	760	820	870	930	990	1050	1160	990
6	Hornbeam	810	830	840	860	930	990	1060	1130	1190	1330	1060
7	Spruce ordinary	450	460	470	490	520	560	600	640	670	750	740
8	Walnut walnut	600	610	630	650	700	750	800	850	900	1000	910
9	Linden	500	530	540	540	580	620	660	710	750	830	760
10	Acacia Belaya	810	830	840	860	930	990	1060	1190	1300	1330	1030
11	Alder	530	540	560	570	620	660	700	750	790	880	810
12	Maple	700	720	740	760	820	870	930	990	1050	1160	870
13	Clean ordinary	690	710	730	740	800	860	920	930	1030	1150	960
14	Fir Siberian	380	390	400	410	440	470	510	540	570	630	680
15	Pine ordinary	510	520	540	550	590	640	680	720	760	850	820
16	Fir Caucasian	440	450	460	480	510	550	580	620	660	730	720
17	Pine cedar	440	450	460	480	510	550	580	620	660	730	760
18	Birch	640	650	670	680	730	790	840	890	940	1050	870
19	Aspen	500	510	530	540	580	620	660	710	750	830	760

* Fresh. - Fresed tree

Versions of the specific weight of pine wood, lumber from coniferous wood.

How much is the share of pine? The proportion of pine is measured in kg / m3 and is determined by the density of pine wood measured in GR / cm3. In contrast to many other materials, a tree, in particular, the coniferous wood pine, is characterized by not one value of the specific weight, but a fairly wide spectrum of values. The fact is that pine, like any other tree, is a porous natural material having a natural humidity. In other words, pine wood always contains some amount of water, which significantly affects its density, and therefore on the proportion of pine. In general, the question of which proportion of pine should not have a practical sense, without clarifying the moisture content of the tree sample. And the moisture content of pine wood can fluctuate in the large range. For example: the specific weight of the pine in the natural humidity, the proportion of pine in the freshly powerful state, the proportion of wet, raw, wet, dried, dried, dry and absolutely dry pine wood. The quality of pine wood is reflected in the forties of coniferous lumber, for example: 1 grade pine, pine 2 grades, pine 3 varieties. For each grade of pine, the density and proportion of the tree will be different. Although the determining parameter for the value of the specific gravity still remains the moisture of wood. However, with the same humidity of the tree, for example, 12%, the proportion of pine 1, 2 and 3 varieties will be different.

Changing the specific pine weight.

The highest proportion of growing, not yet sawed and non-searched pine. This is due to the highest possible meaning of the moisture content of the tree in the state of the root. What is the proportion of pine in the natural state? The fact is that the natural moisture content of pine wood is not normalized in advance, as a reference parameter, but is actually determined. And heavily depends on the conditions of growing coniferous wood, as well as the seasons of the billet of pine wood. It can fluctuate in the range from 29 to 81%. Accordingly, the natural proportion of pine may vary in the same wide range of values. From a practical point of view, the proportion of natural humidity is usually little interesting, as it is an initial characteristic and changes quickly. Already in a freshly powerful state, the proportion of pine is reduced from the initial value, the one that was in the natural state "on the root". With all types of storage and transportation, even without a special drying, pine wood loses moisture, dries and the proportion of pine is reduced. The lowest, smallest density and the smallest proportion of pine in a completely dry state, precisely because the humidity of such coniferous wood is very small.

Almost important values \u200b\u200bof the specific pine weight.

When processing coniferous wood, sale of pine lumber, the use of wood in the construction and manufacture of carpentry made of pine. Practical interest is the proportion of wet (wet, raw, dried) and dry pine. At the same time, despite the fact that the names of the tree, like: wet, raw, wet pine wood are widely used by coniferous wood, trading organizations and woodworking machines, joiners. There is no clear specific binding of such definitions to specific values \u200b\u200bof humidity in percentage. Drier pine is freshly stained pine wood for a long time stored in the conditions under which the natural drying of the tree happened. Its actual density and proportion can also be different and is not normalized by any norms and rules (SNiP, GOST). Dry pine is a coniferous wood that has been suspended special drying. However, for specific products and types of work, the humidity of dry pine is determined by special requirements precisely to these products made of pine wood and is regulated by GOST and SNiP separately. For example, in the manufacture of products and structures from wood, designed for operation on the street, the dry pine is considered that wood, in which the humidity is 11 - 14%. For wooden products from pine used in residential areas, a dry tree is wood with humidity: 8 - 10%. And for parquet is used dry pine with parquet floors 6 - 8%. So the proportion of dry pine is also indicated in accordance with the technological requirements for the humidity of the tree, for specific products and types of work. Therefore, technically competently and correctly from a technological point of view to operate with specific pine weights using not common terms: wet, wet, raw, dry wood. And indicate the values \u200b\u200bof the specific pine weight only in binding to the moisture content of the tree. As additional information needs to be taken into account the grade of coniferous lumber: the specific weight of the pine is 1 grade, 2 varieties and 3 varieties. Specific values \u200b\u200bof the specific gravity of pine wood for a different moisture content of the tree (kg / m3) and the corresponding pine density (GR / cm3) can be found in Table 1.

Pine specific weight. Specific pine weight? See the answer in Table 1.

Table 1. Pine specific weight. Specific pine weight? Density values \u200b\u200bwith different moisture content of pine wood. See the answer in Table 1..