What is the specific gravity of pine? Specific gravity pine is measured in kg/m3 and is determined by the density of pine wood measured in g/cm3. Unlike many other materials, wood, in particular pine coniferous wood, is characterized not by one specific gravity value, but by a fairly wide range of values. The fact is that pine, like any other tree, is porous natural material having natural moisture. In other words, pine wood always contains some amount of water, which significantly affects its density, and therefore the specific gravity of pine. In general, the question of what is the specific gravity of pine has no practical meaning, without specifying the moisture content of the wood sample. And the moisture content of pine wood can fluctuate over a wide range. They distinguish, for example: the specific gravity of pine at natural humidity, specific gravity of pine in a freshly cut state, specific gravity of wet, damp, damp, dried, dried, dry and absolutely dry pine wood. The quality of pine wood is reflected in the grade of softwood lumber, for example: 1st grade pine, 2nd grade pine, 3rd grade pine. For each variety of pine, the density and specific gravity of the tree will be different. Although the determining parameter for the specific gravity value still remains the moisture content of the wood. However, with the same wood moisture content, for example 12%, the specific gravity of grade 1, 2 and 3 pine will be different.
Change in the specific gravity of pine.The highest specific gravity is for growing, not yet cut down or felled pine. This is due to the maximum moisture content of the tree in the “standing” state. What is the specific gravity of pine in natural state? The fact is that the natural moisture content of pine wood is not standardized in advance as a reference parameter, but is actually determined. And it depends greatly on the growing conditions. coniferous tree, as well as the pine timber harvesting season. It can range from 29 to 81%. Accordingly, the natural specific gravity of pine can vary in the same wide range of values. WITH practical point From a perspective, specific gravity at natural humidity is usually of little interest, since it is an initial characteristic and changes quickly. Already in the freshly cut state, the specific gravity of the pine tree decreases from its initial value, the one that was in its natural state “on the root.” With all types of storage and transportation, even without special drying, pine wood loses moisture, dries and the specific gravity of pine decreases. Pine has the lowest, lowest density and lowest specific gravity in an absolutely dry state, precisely because the moisture content of such coniferous wood is very low.
Practically important values specific gravity of pine.When processing coniferous wood, selling pine lumber, using wood in construction and making pine carpentry. Of practical interest is the specific gravity of wet (moist, damp, dried) and dry pine. At the same time, despite the fact that such tree names as: wet, damp, damp pine wood are widely used by coniferous wood harvesters, trading organizations and woodworkers, carpenters. There is no clear specific connection of such definitions to specific percentage humidity values. Dried pine is freshly cut pine wood for a long time stored in conditions under which natural drying of the wood occurred “along the way.” Its actual density and specific gravity can also be different and are not standardized by any norms and rules (SNiP, GOST). Dry pine is coniferous wood that has been specially dried. However, for specific products and types of work, the moisture content of dry pine is determined special requirements It is precisely these pine wood products that are regulated by GOST and SNiP separately. For example, in the manufacture of wooden products and structures intended for use outdoors, dry pine is considered to be wood with a moisture content of 11–14%. For wooden products from pine used in residential premises, dry wood is wood with a moisture content of 8 - 10%. And for parquet, dry pine with moisture is used parquet board 6 – 8%. So the specific gravity of dry pine is also indicated in accordance with the technological requirements for wood moisture content, for specific products and types of work. Therefore, it is technically competent and correct from a technological point of view to operate with the values of the specific gravity of pine using not general terms: wet, damp, damp, dry wood. And indicate the specific gravity of pine only in relation to the moisture content of the tree. How Additional information it is necessary to take into account the grade of coniferous lumber: the specific gravity of pine of 1st grade, 2nd grade and 3rd grade. Specific values of the specific gravity of pine wood for different wood moisture content (kg/m3) and the corresponding density of pine (g/cm3) can be found in Table 1.
Pine specific gravity. Specific gravity of pine? See the answer in Table 1.Table 1. Pine specific gravity. Specific gravity of pine? Density values at different humidity levels of pine wood. See the answer in table 1. .
For the manufacture of various building materials from wood (lining, boards, slats, timber), materials with natural moisture are used. However, according to the requirements of GOST and building regulations Raw wood floorboards must be dried before installation. This indicator determines how much a cube of natural moisture board weighs. Although the price of the material is charged for its volume, the weight of the board with natural moisture is important when transporting products. We will tell you how much a cube of natural moisture board of different types weighs.
Concept of material moisture
Before we tell you how much natural moisture edged boards and other lumber weigh, you need to understand the basic concepts. Different types of wood are used to make tongue-and-groove, decking, planed and edged boards. Each rock has its own specific hygroscopicity, that is, the ability to absorb moisture from the air.
Depending on the absorption of moisture, porosity and the structure of cell membranes, each type of wood has its own absolute humidity. The maximum value of this indicator is 30.
In addition, a board with natural humidity can absorb water through direct contact with it during precipitation or when a room is flooded. Dampness in the room also causes wood to absorb moisture. If ambient air becomes very dry, it gives off moisture.
Important! Most often, moisture loss occurs through the ends of the product.
The normal process of wood absorbing and releasing moisture is called “breathing.” Equilibrium humidity is a condition in which there is a balance of water between environment And internal space wood.
The indicator of natural saturation with water depends on the location of the fibers in the structure. Moisture evaporates faster in the longitudinal direction of the fibers, rather than in the transverse direction. That is why a floor made from planks of natural moisture releases moisture faster at the ends of the floorboards.
To understand what it is batten ordinary humidity, you need to understand the concept of absolute and relative humidity:
- Relative saturation Moisture is the percentage of its mass in wood to the mass of the wet product.
- Absolute indicator always more relative. This is a percentage expression of the ratio of the mass of moisture in wood to the weight of ordinary dry material.
Important! Because hygroscopic intracellular fluid collects in the cell walls, it is more difficult to remove. In this regard, hygroscopic moisture has a greater effect on the geometry of the board, its weight and characteristics.
The weight of the edged board of natural moisture also depends on the unbound free liquid in the material, which collects in the intercellular spaces and inside the cells. Such moisture evaporates quickly and does not affect the characteristics of the product.
Natural moisture content is the moisture content in freshly cut wood that has not been dried. This non-standardized indicator can be in the range of 30-80 percent. The weight of 1 m3 of edged boards with natural moisture content depends on:
- the conditions in which the tree grows;
- the season when the sawing was done (winter wood is less saturated with moisture than that which was cut in the summer season).
Dependence of board weight on moisture
If you need a board with natural moisture, the price depends on the weight of the cube of material and its moisture saturation:
- semi-dry products have a humidity of 18 to 23 percent;
- a raw product with a moisture content of more than 23% is the cheapest - from $30 per cubic meter;
- dry edged board with humidity within 12-18 percent costs $40-50 per cubic meter;
- dry lumber with a humidity of 6-12 percent are the most expensive - from $60 per m³.
Depending on the dampness, the weight of the material also changes. For example, a cube of wet oak floorboards weighs 990 cwt. If the material is dried to a moisture content of 10%, then the mass of the cube will decrease to 0.67 tons. But the price for dried lumber will increase.
The increase in price depending on moisture saturation is justified by the fact that the characteristics of the product also increase:
- dried wood has stable geometric dimensions;
- it is resistant to rotting;
- the material is durable and flexible;
- wood is quickly and easily processed;
- ensures strong fixation by adhesive method;
- the product will last longer.
Attention! Damp wood is susceptible to mold, rot and warping. Ideally, the moisture content of the lumber is brought to the level at which shrinkage and swelling of the wood stops. That is why the cost of such products is the highest.
How much does a cube of boards from different types weigh?
The weight of a cube of material is directly related to the type of wood from which it is made:
- Oak board with natural humidity weighs 990 c/m³. A cube of dried wood weighs 670 centners.
- Wet pine floorboards weigh 820 c/cu.m. The dried elements have a weight of 470 c/m³.
- Cube of boards damp spruce wood weighs 760 c, and a dried board weighs 420 c.
- Products made from wet larch have a weight of 940 c/cu. A cube of dry larch weighs 630 c.
- Birch lumber undried ones weigh 870 c/m³, and dry ones weigh 600 c/m³.
- Aspen floorboards from wet wood - 760 c/cubic meter, and dried wood - 470 cbm.
- Alder wood cube after cutting it weighs 810 quintals, and the dried material weighs 490 quintals.
Why is it necessary to know the weight of a cubic meter of wood?
Since the manufacturer charges the price for lumber depending on the type of wood, moisture content and volume, the weight of the material is not taken into account. This indicator will be needed when transporting lumber, since the choice of vehicle and the cost of transportation depend on it.
Also, the weight of wood is taken into account when calculating loads on building construction. As a rule, an ordinary consumer does not need such a calculation. It is done by designers and planners at the project development stage.
Artificial and natural drying
Natural drying of lumber is very slow and takes a long time. However, this drying process is considered the most gentle, since cracks and other deformation defects do not appear in the wood. With aggressive chamber drying there is a high probability of cracking and deformation of the lumber.
Important! Natural drying is carried out in a special well-ventilated place, which is reliably protected from atmospheric moisture and direct sunlight.
The humidity of freshly cut wood reaches 50-80%. With natural drying, this figure drops to 18-22 percent. This drying method is the easiest to organize, since it does not require the use of special equipment and compliance with certain rules. temperature regime. Flaws natural drying– duration of the process and low intensity.
Artificial drying in chambers proceeds much faster. At the same time, the humidity indicator is reduced to 10-18 percent. During the drying process, you can adjust the temperature and control the entire process. Products placed in stacks are placed in the chambers, each of which contains lumber of the same thickness and species.
Advantages of artificial drying:
- protection against mold and rot;
- You can dry wood treated with special protective compounds;
- speed of drying (usually it takes a week).
There are specific gravity of wood (hard wood pulp without voids) and the specific gravity of wood as a physical body. The specific gravity of wood matter is above unity and depends little on the type of wood; on average it is taken equal to 1.54. The specific gravity of the wood substance is important in determining the porosity of wood. The conventional volumetric weight has the advantage over the volumetric weight that it does not depend on the amount of shrinkage and does not require recalculation to 15% humidity. This makes it possible to significantly simplify calculations and provide more uniform results when determining the γconditions of several samples.
Classification of rocks by density
The density values of different types of wood differ quite significantly. Based on standard moisture content, rocks are usually divided into three groups:
– low-density species (540 kg/m3 or less): conifers - pine, spruce (all types), fir (all types), cedar (all types), common juniper; from deciduous trees - poplar (all types), linden (all types), willow (all types), black and white alder, chestnut, white, gray and Manchurian walnut, Amur velvet;
– medium density species (540-740 kg/m3): conifers - larch (all types), yew; from deciduous - drooping, fluffy, black and yellow; eastern and European beech, elm, pear, summer oak, eastern, swamp, Mongolian; elm, elm, maple (all types), hazel, walnut, plane tree, rowan, persimmon, apple, common and Manchurian;
– breeds high density(750 kg/m3 and above): white and sand acacia, iron acacia, Caspian honey locust, white hickory, hornbeam, chestnut-leaved and Araksin oak, iron wood, boxwood, pistachio, hop hornbeam.
Among the foreign species, there are those whose wood has both a very low density (balsa - 120 kg/m3) and a very high density (backout - 1300 kg/m3).
The tables of the State System of Standard Reference Data (GSSSD), published by Gosstandart of Russia (“Wood. Indicators of physical and mechanical properties of small samples without defects”), provide more detailed information on the density of wood, indicating the type of tree species and the area of its growth.
The density of bark has been studied much less than that of wood. The available data are very varied.
Comparison of these data with the average density of wood at standard humidity shows that the density of pine bark is 30-35% greater than wood, spruce - 60-65%, and birch - 15-20%.
The influence of wood structure on its properties
The density of wood is also greatly influenced by the water it contains. Firstly, it increases the mass of the sample, and secondly, the swelling of cell walls in water causes a change in the volume of the sample. Therefore, the density of wood is determined either in the absence of water or at a certain mass fraction of it in the wood. Completely dried samples actively absorb water vapor from the surrounding air and in some cases it is more convenient to handle wood samples containing known quantity water and are in relative equilibrium with the surrounding atmosphere. In technological calculations, the basic density of wood is sometimes used, which is the ratio of the mass of an absolutely dry wood sample to its volume in the most swollen state. This condition is typical for freshly cut wood and wood that has been long time in contact with water. In this case, the basic relative density is actually determined; however, by equating 1 g of displaced water to a volume of 1 cm3, they transform it from a dimensionless quantity into a quantity that has dimension.
Tree species are characterized certain values wood density, which is influenced by growing conditions. Depending on the botanical species, the density of wood varies widely. For example, for tree species common in Russia, the density of absolutely dry wood varies from 350 kg/m3 for Siberian fir to 920 kg/m3 for iron birch.
Based on the density of wood at a humidity of 12%, all domestic species are divided into three groups: with low density (540 kg/m3 or less) - spruce, fir, pine, cedar pine, poplar, willow, linden, alder; medium density (550...740 kg/m3) - larch, birch, beech, oak, elm, maple, ash; high density (750 kg/m3 or more) - acacia, hornbeam, individual species birch, oak, ash. It should be noted that coniferous wood, with the exception of larch and some types of pine, has low density. 
Closely related to this is the property of permeability to liquids and gases. The permeability of wood 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 a system of cell cavities and intercellular spaces communicating through the pores. A dry cell wall, as already noted, has low porosity, and its components are either included in crystalline regions or are in a glassy state, which makes the cell wall practically impermeable to non-polar environments. In polar liquids, cell walls swell greatly 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 testing wood for gas permeability requires much less time, in practice, to assess the permeability of wood, its gas permeability is often determined.
The permeability of wood, estimated by the mass or volumetric flow rate of a liquid or gas through a unit surface area of a wood sample, is maximum in the axial direction, i.e. along the fibers. It is several times higher than in conifers, since it coincides with the direction of the vessels. The permeability across the fibers is much less and is greatly influenced by the medullary rays. The formation of mature and especially heartwood reduces permeability, and in certain species the heartwood becomes waterproof.
What is the density of oak, beech and other species?
In the descriptions interior doors and the tree species from which they are made, the term “wood density” often slips through. Descriptions are good, but they don't provide as clear an understanding as numbers - what does "a little tighter" mean? Values in the form of numbers give an accurate picture, on the basis of which you yourself can decide which wood is most suitable for making interior doors. 
Before moving on to the numbers, let’s define what wood density is and why you need to know it.
The density of wood is the ratio of its mass to volume. Simply put, the more a cubic meter of wood weighs, the denser it is. The density of wood, called , depends on humidity, so it is customary to operate with values obtained at a humidity of 12%.
We've sorted out the first question, let's move on to the second. The density of wood directly affects two important properties- strength and hygroscopicity. Dense wood has higher strength and, in most cases, hygroscopicity. The latter term means that doors made of high-density wood are more susceptible to changes in humidity - everyone knows that wood tends to absorb moisture and expand. For this reason, doors made of aspen, linden or pine, located at the very bottom of the table, are used in saunas and baths, where beech doors would simply stop closing.
Values are given in grams per cubic centimeter(g/cm3) at a humidity of 12%. Please note that in some cases average values are given.
Brief description of wood properties: Hornbeam.
Hornbeam is most widely distributed in Europe, Asia Minor and Iran. The wood is shiny, heavy, sticky. Color: whitish-gray. Density: 750 kg/m (cube). Brinell hardness: 3.5.
Lacewood. One of the most beautiful Australian trees. The color is light brown with a characteristic grain. Density: 910-1050 kg/m (cube). Brinell hardness: 5.5. Paduc. with bright positive energy. Color: Light yellowish-red to dark brick-red, mottled with darker lines. Density: 850-950 kg/m (cube). Brinell hardness: 4.2.
Wenge. The homeland of wenge wood is the tropical jungle of West Africa, all the way to Zaire. The structure of the material is large, even-grained, the wood is decorative and at the same time heavy and resistant to pressure and bending. Color: Golden brown to very dark brown with black streaks. Density: 850-900 kg/m (cube). Brinell hardness: 4.1.
Tigerwood (tiger tree). Grows in Western Tropical Africa. Colour: Yellowish-brown, sometimes marked with dark stripes called "veins". Density: 800-900 kg/m (cube). Brinell hardness: 4.1.
Cocobolo. High stability when changing humidity. Color: dark, deep red with black, irregular stripes. Bright, expressive, beautiful texture. Density: 800-980 kg/m (cube). Brinell hardness: 4.35.
Rosewood. The wood is very dense and heavy, polishes well, and sinks in the input. Color: attractive light brown with a violet-lilac tint. Density: 1000 kg/m(cube). Brinell 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, the yarra darkens and its color can take on very diverse shades. Density: 820-850 kg/m(cube). Brinell hardness: 5.0.
Pear. The wood is dense, hard, easy to process, and rarely cracks. Color: from yellowish-white to brownish-red. To increase hardness, pear wood is placed in water and kept for a long time, after which it is dried for a long time in natural conditions. After drying, it acquires a brownish tint. Density: 700 kg/m (cube). Brinell hardness: 3.4. Oak (stained). The wood is strong, durable, resistant to external influences. After a long (50 to 300 years) soaking (staining) without oxygen, the wood acquires a velvety black color. Black color.
Precious bog oak wood material. For thousands of years, sunken oak trunks were located at the bottom of reservoirs, where, without access to air, during the process of staining they acquired strength not inferior to stone. Nature itself gives it strength, durability and unique color scheme. Density: 750 kg/m (cube). Brinell hardness: 3.8. Boxwood. The wood is hard as bone, its specific gravity is greater than the specific gravity of water, boxwood sinks in water. Therefore, it is used for the manufacture of parts where significant rigidity is required. Color: light yellow, matte. Density: 1350 kg/m (cube). Brinell hardness: over 8.0. Makassar. A type of ebony common in Southeast Asia. Color: dark brown with black veins. Has very beautiful texture. Density: 1000 kg/m (cube). Brinell hardness: 7.0.
Eben. In trade there are many varieties of ebony. The rarest and most expensive grows only in the countries of Central Africa. So expensive that payment for it is in kilograms. Export supplies of African ebony are limited and are completely controlled by the governments of the countries where it is mined. The wood is very dense and heavy and sinks in water. Color: dark brown to velvety black with characteristic lighter (or light brown) longitudinal veins. Density: 1200 kg/m (cube). Brinell hardness: over 8.0. Jatoba. It is also called Brazilian cherry. The wood is heavy, durable, hard and at the same time surprisingly elastic. It is difficult to process, but can be ground and polished almost to mirror shine. Color: Density: 960 kg/m (cube). Brinell hardness: 4.8. Zebrano. Grows in Gabon and Cameroon. The wood is hard and heavy. The surface is shiny, the texture is somewhat coarse. Color: light golden with narrow streaks ranging from dark brown to almost black. Density: 900 kg/m (cube). Brinell hardness: 4.5. Kewasingo. It grows from equatorial Africa, from Cameroon and Gabon to the Congo. Tree up to 35-40 meters tall, trunk diameter up to 1.5-2 meters. The wood is red-brown to dark red in color. It has beautiful drawing textures. Dense, hard, stable. Density: 820-850 kg/m(cube). Brinell hardness: 5.0.
Black hornbeam. Grown in the Caucasus mountains. The tree was felled in winter when sap flow has stopped. The secret of painting is passed down from generation to generation. Black color. Density: 700 kg/m(cube). Brinell hardness: 3.4. Merbau. Grows in South-East Asia(Malaysia, Indonesia, Philippines). The main advantages of merbau are that it contains oily substances in its pores, is very hard, resistant to moisture and does not dry out much. During use, merbau darkens, especially the light areas, as a result of which the color of the wood as a whole is evened out. Color: brown, from light to dark tones, interspersed with yellow streaks in places. Density: 840 kg/cub.m. Brinell hardness: 4.1. Ash. The wood is heavy, hard with high strength. Possessing toughness and one of the most valuable rocks in the world for manufacturing sports equipment. Density: 700 kg/m(cube). Brinell hardness: 4.0-4.1.
Density of wood at different humidity levels
One of the most important factors When organizing timber transportation, the density of the tree is determined. She happens to be important indicator when calculating the cost of transportation and selection of a timber truck.
The weight of wood can be specific or volumetric. Specific gravity - the mass of a unit volume of wood without taking into account species, moisture and other factors - is 1540 kg/m3. Volume weight- mass per unit volume of wood, taking into account moisture and species. Based on the volumetric weight, the density of the tree can be determined. The density of trees of different species is different. Also, the density of a tree of one species is highly variable, depending on the geographical location and type of forest.
As the moisture content of the wood increases, the density increases. For example, at a humidity of 15% - 0.51 t/m3, and at a humidity of 70% - 0.72 t/m3. According to the degree of humidity, the tree is divided into: absolutely dry (humidity - 0%, only in laboratory conditions), room-dry (humidity up to 10%), air-dry (humidity - 15-20%), freshly cut (humidity 50-100%) , wet (over 100%, when storing wood in water).
The density of wood is as a construction raw material.
Wood density - the ratio of wood mass to volume Рw=Mw/Vw
Density depends on the rock and humidity, usually determined from a table. All tree species are divided into 3 groups:
1)Low-density P<0,5(г.см3)(сосна,ель, (пихта, кедр, осина, ольха, липа, тополь)
2) Medium density 0.5
This property is characterized by the mass of a unit volume of material, and has a dimension in kg/m3 or g/cm3.
a) Density of wood substance pd.v., g/cm, i.e. the density of the cell wall material is equal to: pd.v. = md.v. / vd.v., where md.v. and vd.v. - respectively, the mass, g, and volume, cm3, of the wood substance.
This indicator is equal to 1.53 g/cm3 for all species, since the chemical composition of the cell walls of wood is the same.
b) The density of absolutely dry wood p0 is equal to: p0 = m0 / v0, where m0, v0 are, respectively, the mass and volume of wood at W = 0%.
The density of wood is less than the density of wood substance, since it includes voids (cell cavities and intercellular spaces filled with air).
The relative volume of cavities filled with air characterizes the porosity of wood P: P = (v0 - vd.v.) / v0 * 100, where v0 and vd.v. - respectively, the volume of the sample and the wood substance contained in it at W = 0%. Wood porosity ranges from 40 to 80%.
c) Density of wet wood: pw = mw / vw, where mw and vw are, respectively, the mass and volume of wood at humidity W. The density of wood depends on its moisture content. At humidity W< Wпн плотность изменяется незначительно, а при увеличении влажности выше Wпн наблюдается значительный рост плотности древесины
d) Partial moisture content of wood p`w characterizes the content (mass) of dry wood per unit volume of wet wood: p`w = m0 / vw, where m0 is the mass of absolutely dry wood, g or kg; vw is the volume, cm3 or m3, of wood at a given moisture content W.
e) The basic density of wood is expressed by the ratio of the mass of an absolutely dry sample m0 to its volume at a moisture content equal to or higher than the cell wall saturation limit Vmax: pB = m0 / vmax. This basic indicator of density, which is independent of humidity, is widely used to assess the quality of raw materials in the pulp and paper industry and in other cases.
The density of wood varies over a very wide range. Among the species of Russia and neighboring countries, the wood with very low density is Siberian fir (345), white willow (415), and the most dense is boxwood (1040), pistachio core (1100). The range of changes in the density of foreign wood species is wider: from 100-130 (balsa) to 1300 (backout). Density values here and below are given in kilograms per cubic meter (kg/m3).
According to the density of wood at 12% moisture content, the species are divided into 3 groups: low (P12< 540), средней (550 < P12 < 740) и высокой (P12 >740) wood density.
The volumetric weight of wood also depends on the width of the annual layer. In deciduous trees, the volumetric weight decreases with decreasing width of the annual layers. The greater the average width of the growth ring, the greater the volumetric weight of the same breed. This dependence is very noticeable in ring-pore rocks and somewhat less noticeable in open-pore rocks. In conifers, an inverse relationship is usually observed: the volumetric weight increases with a decrease in the width of the growth rings, although there are exceptions to this rule.
The volumetric weight of wood decreases from the base of the trunk to the top. In middle-aged pines this drop reaches 21% (at a height of 12 m), in old pines it reaches 27% (at a height of 18 m).
The decrease in volumetric weight along the height of the trunk reaches 15% (at the age of 60-70 years, at a height of 12 m).
There is no pattern in changes in the volumetric weight of wood along the diameter of the trunk: in some species the volumetric weight decreases slightly in the direction from the center to the periphery, in others it increases slightly.
A big difference is observed in the volumetric weight of early and late wood. Thus, the ratio of the volumetric weight of early wood to the weight of late wood in Oregon pine is 1: 3, in pine 1: 2.4, in larch 1: 3. Therefore, in coniferous species, the volumetric weight increases with an increase in the content of late wood.
Wood porosity. Wood porosity refers to the volume of pores as a percentage of the total volume of absolutely dry wood. Porosity depends on the volumetric weight of the wood: the higher the volumetric weight, the less porosity.
To approximately determine porosity, you can use the following formula:
C = 100 (1-0.65γ 0)%
where C is the porosity of wood in%, γ 0 is the volumetric weight of absolutely dry wood.
The table shows the weight of 1 m3 of wood relative to the percentage of moisture.
It varies widely even for one type of wood. The values of the density (specific gravity) of wood are generalized figures. The practical value of wood density differs from the average table value given and this is not an error.
Table of density (specific gravity) of wood
depending on the type of wood
| "Handbook of masses of aviation materials" ed. "Mechanical Engineering" Moscow 1975 | Kolominova M.V., Guidelines for students of specialty 250401 “Forest Engineering”, Ukhta USTU 2010 | |||
| Wood species | Density wood, (kg/m3) |
Limit density wood, (kg/m3) |
Density wood, (kg/m3) |
Limit density wood, (kg/m3) |
| Ebony (black) |
1260 | 1260 | --- | --- |
| Backout (iron) |
1250 | 1170-1390 | 1300 | --- |
| Oak | 810 | 690-1030 | 655 | 570-690 |
| Red tree | 800 | 560-1060 | --- | --- |
| Ash | 750 | 520-950 | 650 | 560-680 |
| Rowan (tree) | 730 | 690-890 | --- | --- |
| Apple tree | 720 | 660-840 | --- | --- |
| Beech | 680 | 620-820 | 650 | 560-680 |
| Acacia | 670 | 580-850 | 770 | 650-800 |
| Elm | 660 | 560-820 | 620 | 535-650 |
| Hornbeam | --- | --- | 760 | 740-795 |
| Larch | 635 | 540-665 | 635 | 540-665 |
| Maple | 650 | 530-810 | 655 | 570-690 |
| Birch | 650 | 510-770 | 620 | 520-640 |
| Pear | 650 | 610-730 | 670 | 585-710 |
| Chestnut | 650 | 600-720 | --- | --- |
| Cedar | 570 | 560-580 | 405 | 360-435 |
| Pine | 520 | 310-760 | 480 | 415-505 |
| Linden | 510 | 440-800 | 470 | 410-495 |
| Alder | 500 | 470-580 | 495 | 430-525 |
| Aspen | 470 | 460-550 | 465 | 400-495 |
| Willow | 490 | 460-590 | 425 | 380-455 |
| Spruce | 450 | 370-750 | 420 | 365-445 |
| Willow | 450 | 420-500 | --- | --- |
| Hazelnut | 430 | 420-450 | --- | --- |
| Walnut | --- | --- | 560 | 490-590 |
| Fir | 410 | 350-600 | 350 | 310-375 |
| Bamboo | 400 | 395-405 | --- | --- |
| Poplar | 400 | 390-590 | 425 | 375-455 |
- The table shows the density of wood at a humidity of 12%.
- The table indicators are taken from the “Handbook of Masses of Aviation Materials” ed. "Mechanical Engineering" Moscow 1975
- Corrected on March 31, 2014, according to the method:
Kolominova M.V., Physical properties of wood: guidelines for students of specialty 250401 “Forest Engineering”, Ukhta: USTU, 2010
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It is generally accepted to indicate the density (specific gravity) of wood depending on the type of wood. The indicator is taken to be the average value of the specific gravity, obtained by summarizing the results of repeated practical measurements. In fact, two wood density tables are published here, taken from completely different sources. A small difference in the indicators clearly indicates the variability of the density (specific gravity) of wood. When analyzing the wood density values from the table above, it is worth paying attention to the differences between the indicators in the aviation reference book and the university manual. For objectivity, the value of wood density from both documents is given. With the right for the reader to choose the priority of the importance of the original source.
Particularly surprising is the tabular density value larches- 540-665 kg/m3. Some online sources indicate the density of larch as 1450 kg/m3. It is not clear who to believe, which once again proves the uncertainty and unknown nature of the topic being raised. Larch is a fairly heavy material, but not so heavy as to sink like a stone in water.
The influence of humidity on the specific gravity of wood
Specific gravity of driftwood
It is noteworthy that with an increase in wood moisture content, the dependence of the specific gravity of this material on the type of wood decreases. The specific gravity of driftwood (humidity 75-85%) practically does not depend on the type of wood and is approximately 920-970 kg/m3. This phenomenon is explained quite simply. The voids and pores in wood are filled with water, the density (specific gravity) of which is much higher than the density of the displaced air. In terms of its value, the density of water approaches the density of , the specific gravity of which practically does not depend on the type of wood. Thus, the specific gravity of pieces of wood soggy in water is less dependent on its species than in the case of dry samples. At this point it is worth remembering that for wood there is a division of classical physical concepts. (cm. )
Wood Density Groups
Conventionally, all tree species are divided into three groups
(according to the density of its wood, at a humidity of 12%):
- Low density rocks(up to 540 kg/m3) - spruce, pine, fir, cedar, juniper, poplar, linden, willow, aspen, black and white alder, chestnut, white, gray and Manchurian walnut, Amur velvet;
- Medium density rocks(550-740 kg/m3) - larch, yew, silver birch, downy, black and yellow, eastern and European beech, elm, pear, summer oak, eastern, swamp, Mongolian, elm, elm, maple, hazel, walnut , plane tree, rowan, persimmon, apple tree, common ash and Manchurian;
- High Density Rocks(750 kg/m3 and above) - white and sand acacia, iron birch, Caspian honey locust, white hickory, hornbeam, chestnut-leaved and Araxinian oak, ironwood, boxwood, pistachio, hop hornbeam.
Density of wood and its calorific value
The density (specific gravity) of wood is the main indicator of its heating energy value - . The dependence here is direct. The higher the density of the wood structure of a tree species, the more combustible wood substance it contains and the hotter such trees are.
Before carrying out any construction or repair, always calculate the required amount of material. For example: brick, rolled metal or lumber: unedged, edged boards or lining. Usually the seller provides wood delivery services, but it happens that this is not possible. And this question has to be decided by the buyer himself: what kind of machine should he order in order to bring the required amount of timber to the construction site?
Features of lumber
Even if the amount of wood in cubic meters is known, then the choice of machine in terms of carrying capacity will still need to be calculated. Even knowing how much a cube of dry board weighs, the weight of a cubic meter of material on the market can vary significantly. And the reason for this will not only be the type of tree, for example: pine or spruce, birch or cedar, but also the location of the log house, the humidity of the surrounding air, and even the time that has passed since the day of the log house. The weight of a unit of cubic meter of the same wood will also differ from the degree of processing of the material. The mass of round timber, under the same conditions, will always be less than the mass of unedged timber. This is due to the fact that the density of the material in one cube will be different. It is not possible to stack the round timber tightly on top of each other; large voids will remain. The same applies to unedged boards. The surface will not press tightly on the sides.
Therefore, when calculating the carrying capacity of a vehicle, you need to focus on transporting the maximum possible weight of cargo. This means you need to find out how much a cube of edged pine boards of natural moisture weighs? Since this is the state of the tree at the time of its felling, and therefore the maximum humidity and density.
Indicators affecting the weight of lumber
Wood moisture content is a very important indicator that you need to pay attention to. When it is high, the tree swells, and when it is low, on the contrary, it dries out. It is recommended to carry out all construction work with already dried lumber, in which the moisture content does not exceed 15-20%. Otherwise, the installed damp wood, as it dries over time, will change its geometric dimensions (shrink) and thereby violate the integrity of the building.
Dried wood becomes more durable, lends itself well to finishing, is not susceptible to mold and insects, and retains its construction qualities for a long time. Before drying, the remaining bark is removed. This is necessary for uniform drying and to prevent damage by insects (bark beetles).
Wood drying is carried out by specialists in the open air. The timber is stacked on spacers between the rows so that air can pass freely and dry the boards on all sides. It is advisable to locate the drying area in a place where the material is not exposed to direct sunlight, but there is good ventilation. The top row of the stack must be pressed with a load to prevent deformation.
Weight calculation
Now let's calculate the weight of the most common lumber that you can encounter on the market.
We will calculate the mass using a calculator using the formula M=V*ρ, kg, where:
- V is the volume of material required for calculation, m3. In our case, this value is 1 m3;
- ρ - wood density, kg/m3. For freshly cut pine the value is 820 kg/m3.
Substituting into the formula, we get:
Similarly, knowing the density of the material, you can calculate how much a cube of larch board weighs:
This means: no matter what size the edged board is:
- 150x150x6000;
- 25x100x6000;
- 25x150x6000;
- 50x150x6000.
Their weight in one cube will be approximately equal, the main thing is that the composition of the wood, as well as the moisture content, remain unchanged, only the number of boards will differ.
The question arises, how much does a cube of dry board of the same pine weigh? This state of wood is accepted when its humidity is up to 20%. In this case, the density is 520 kg/m3.
The difference in the weight of one cube between pine with natural moisture and dry will be 300 kg! But for construction, not 1 m3 is purchased, but for example 100 or 500. Accordingly, the carrying capacity of the vehicle increases by 30 or 50 tons!
Therefore, when choosing lumber, it is important to know the moisture content of the board. So as not to make a mistake in the choice of transport or the number of trips required to transport the entire forest.
rems-info.ru
People who are building their own house or cottage want to know how much 1 cube of board weighs.
How much does a cube of natural moisture board weigh?
1 cube of board weighs 800-1000 kg (depending on the type of wood)
Now you know how much a cube of natural moisture board weighs in tons and you can accurately calculate the required amount.
Previous articleHow much does a cube of crushed stone weigh?Next articleHow much does a cube of pine weigh?
ktoikak.com
How much does a cube of edged board weigh?
We offer you a table of the weight of the main types of wood.
www.xn—-7sb2akllgi.xn--p1ai
How to correctly count a board in cubes.
An edged board differs from an unedged board in that cross section has a regular shape 
rectangle. This allows you to evenly stack it, pack it into even bundles, and quite accurately determine the cubic capacity, that is, the volume of packed materials. If you need to determine the weight of a package, or one cubic meter, it is enough to multiply the volume by the density, which is a reference value and depends on both the type of wood and its humidity, that is, the degree of drying.
For the types of wood most commonly used in construction, you can create a table showing how much a cube of edged board weighs:
Lumber type
Weight of one cubic meter, kg
damp pine
890
Dry pine
470
Raw spruce
790
Dry spruce
450
As can be seen from the table, humidity has a very significant effect on how much a cube of edged board weighs. Such a large dependence is due to the fact that water is present in large quantities in the cellular structure of freshly sawn wood, and if it is not dried properly, its rapid evaporation can lead to significant distortions geometric shape boards, bend them. 
As a result, it can be argued that the weight of a cubic meter of edged board can be determined by the type of wood, classifying it into one of the categories.
Light wood species include pine, fir and others conifers, as well as poplar. Their average density, that is, the weight of a cubic meter fluctuates around the figure of 500 kilograms.
Medium species - a cubic meter of ash, beech, birch - weighs about 650 kilograms.
Heavy species, such as oak or hornbeam, have a density of more than 750 kilograms per cubic meter.
How much does one edged board weigh?
How much does one edged board weigh? The most frequently asked question in search engines is how much does one cube weigh, and as a result, one edged board. I continue the series of articles devoted to edged lumber.
At the insistence of colleagues and regular visitors to the site, I continue the series of articles dedicated to lumber. This article is a continuation of the article “How much does one beam weigh?” We are talking only about pine, 
growing in the territory in the central part of Russia. I’ll immediately make a reservation that pine growing in Siberia has a denser texture, weighs more and costs an order of magnitude more. You can even distinguish it visually, but this is the topic of the next article.
The weight of one cubic meter of freshly cut pine and processed into edged lumber is about 860 kg.
I will present calculations in the form of a table for sections of GOST 8486 boards and recall the calculation formulas.
BOARD SECTION IN MM. QUANTITY, PCS. IN 1m3 MATHEMATICAL ACTION IS THE WEIGHT OF ONE BOARD IN KG.
logo Tiu.ru300х50х6000
11.1 860kg: 11.1pcs. 77.5
logo Tiu.ru250х50х6000
13.3 860kg: 13.3pcs. 64.7
logo Tiu.ru200х50х6000
16.6 860kg: 16.6pcs. 51.8
logo Tiu.ru150х50х6000
22.2 860kg: 22.2pcs. 38.7
logo Tiu.ru100х50х6000
33.3 860kg: 33.3pcs. 25.8
logo Tiu.ru200х40х6000
20.8 860kg: 20.8pcs. 41.4
logo Tiu.ru150х40х6000
27.7 860kg: 27.7pcs. 31.04
logo Tiu.ru100х40х6000
41.6 860kg: 41.6pcs. 20.7
logo Tiu.ru150х30х6000
37.0 860kg: 37.0pcs. 23.2
logo Tiu.ru200х25х6000
33.3 860kg: 33.3pcs. 25.8
logo Tiu.ru150х25х6000 
44.4 860kg: 44.4pcs. 19.3
logo Tiu.ru100х25х6000
66.6 860kg: 66.6pcs. 12.9
To determine for yourself how much a 4000mm and 3000mm long edged board, or another, will weigh. I will give an example of a calculation formula in which a necessary condition for the calculation is the number of pieces per 1 m3.
For a board let's say 150x25x3000mm:
1: 0.15: 0.025: 3 = 88.8 pcs. in 1m3
860kg. : 88.8 pcs. = 10 kg.
The weight of this board with a section of 150x25 and a length of 3000 mm. 10 kg.
For a board 150x50x4000mm:
1: 0.15: 0.05: 4 = 33.3 pcs. in 1m3
860kg. : 33.3 pcs. = 25.8 kg.
The weight of one board with a section of 150x50 and a length of 4000 mm. 26 kg.
At the end of the article, I would like to specially note that these calculations in Moscow markets are the subject of large and small fraud, so each time you need to personally check the “DECLARED DIMENSIONS OF TIMBER”. Like this! (see photo)
The above calculations in the tables are valid only for lumber of clear “DECLARED SIZES” with the correct geometry, i.e., corresponding to GOST 8486-86.
For the “Aerial or Armenian Option” of timber and boards, which are sold cheaply at all sorts of special sales. prices need a separate approach, because the number of pieces. in 1m3 each time it is necessary to calculate separately in accordance with the actual dimensions of the timber and board.
Specific and volumetric gravity of wood - tables
A distinction is made between the specific gravity of wood (solid wood pulp without voids) and the specific gravity of wood as a physical body. The specific gravity of wood matter is above unity and depends little on the type of wood; on average it is taken equal to 1.54. The specific gravity of the wood substance is important in determining the porosity of wood.
Instead of the concept of the specific gravity of wood as a physical body, i.e. the ratio of its weight to the weight of water taken in the same volume at 4°, in practice the volumetric weight of wood is used. Volumetric weight (weight per unit volume of wood) is measured in g/cm3 and is reduced to normal wood moisture content - 15%.
In addition to volumetric weight, sometimes they also use reduced volumetric weight, or conditional volumetric weight. Conditional volumetric weight is the ratio of the weight of a sample in a completely dry state to the volume of the same sample in a freshly chopped state. The value of the conventional volumetric weight is very close to the value of the volumetric weight in an absolutely dry state. The relationship between the conditional volumetric weight (γcond) and the volumetric weight in an absolutely dry state (γ0) is expressed by the formula
γ0 = γcondition/(1-Υ)
where Υ is the total volumetric shrinkage as a percentage, 
γ0 is the volumetric weight of absolutely dry wood.
Volumetric weight of wood.
The conventional volumetric weight has the advantage over the volumetric weight that it does not depend on the amount of shrinkage and does not require recalculation to 15% humidity. This makes it possible to significantly simplify calculations and provide more uniform results when determining the γconditions of several samples.
The volumetric weight of wood depends on humidity, on the width of the annual layer, on the position of the sample in terms of trunk height and diameter. As humidity increases, the volumetric weight increases.
The change in the volumetric weight of wood when dried to a moisture content corresponding to the saturation point of the fibers (23-30%) is proportional to the humidity; after this, the volumetric weight begins to decrease more slowly, as the volume of wood also decreases. When wood moisture content increases, the opposite phenomenon occurs.
The numerical relationship between the volumetric weight of wood and humidity is determined by the following formula:
γw = γ0 (100+W)/(100+(Y0 - Yw))
where γw is the desired volumetric weight at humidity W, γ0 is the volumetric weight in an absolutely dry state, W is the wood moisture content in percent,
Y0 is the total volumetric shrinkage as a percentage when drying to an absolutely dry state and
Yw - volumetric shrinkage as a percentage when drying wood to W% moisture content.
The volumetric weight of wood at a given moisture content can be easily determined with sufficient accuracy using the nomogram proposed by N. S. Selyugin (Fig. 11). Let's assume that we need to determine the weight of 1 m3 of pine wood at a humidity of 80%. According to the table 41a we find the volumetric weight of pine wood at 15% humidity equal to 0.52. On the dotted horizontal line we find the point of volumetric weight 0.52 and from this point we go along the corresponding inclined line of the reduced volumetric weight until it intersects with the horizontal line showing a humidity of 80%. From the intersection point we lower a perpendicular to the horizontal axis, which will show the desired volumetric weight, in this case 0.84. In table 5 shows the weight of wood of some species depending on humidity. furniture restoration
Specific and volumetric weight of wood table Figure 13
Rice. 11. Nomogram for determining the volumetric weight of wood at different humidity levels.
The volumetric weight of wood also depends on the width of the annual layer. In deciduous trees, the volumetric weight decreases with decreasing width of the annual layers. The greater the average width of the growth ring, the greater the volumetric weight of the same breed. This dependence is very noticeable in ring-pore rocks and somewhat less noticeable in open-pore rocks. In conifers, an inverse relationship is usually observed: the volumetric weight increases with a decrease in the width of the growth rings, although there are exceptions to this rule.
The volumetric weight of wood decreases from the base of the trunk to the top. In middle-aged pines this drop reaches 21% (at a height of 12 m), in old pines it reaches 27% (at a height of 18 m).
In birch, the decrease in volumetric weight along the height of the trunk reaches 15% (at the age of 60-70 years, at a height of 12 m).
There is no pattern in changes in the volumetric weight of wood along the diameter of the trunk: in some species the volumetric weight decreases slightly in the direction from the center to the periphery, in others it increases slightly.
A big difference is observed in the volumetric weight of early and late wood. Thus, the ratio of the volumetric weight of early wood to the weight of late wood in Oregon pine is 1: 3, in pine 1: 2.4, in larch 1: 3. Therefore, in coniferous species, the volumetric weight increases with an increase in the content of late wood.
Wood porosity. Wood porosity refers to the volume of pores as a percentage of the total volume of absolutely dry wood. Porosity depends on the volumetric weight of the wood: the higher the volumetric weight, the less porosity.
To approximately determine porosity, you can use the following formula:
C = 100 (1-0.65γ0)%
where C is the porosity of wood in%, γ0 is the volumetric weight of absolutely dry wood.
Table 5 - Approximate weight of 1 m3 of wood of different species in kg
Wood threshold Condition of wood moisture
12-18% 18-23% 23-45% freshly cut
Acacia, beech, hornbeam, oak, ash 700 750 800 1000
Birch, elm, elm, chestnut, larch 600 650 700 900
Willow, alder, aspen, pine 500 550 600 800
Spruce, cedar, linden, fir, poplar 450 500 550 800
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kazap.ru
how much does a cube of pine weigh at natural humidity?
Weight of 1 cube of pine of natural humidity
In chapter Other to the question How much does 1 cubic meter weigh? m pine boards? the best answer given by the author is An edged board differs from an unedged board in that its cross-section has the shape of a regular rectangle. This allows you to evenly stack it, pack it into even bundles, and quite accurately determine the cubic capacity, that is, the volume of packed materials. If you need to determine the weight of a package, or one cubic meter, it is enough to multiply the volume by the density, which is a reference value and depends on both the type of wood and its humidity, that is, the degree of drying.
For the types of wood most commonly used in construction, you can create a table showing how much a cube of edged board weighs:
Lumber type
Weight of one cubic meter, kg
damp pine
890
Dry pine
470
Raw spruce
790
Dry spruce
450
As can be seen from the table, humidity has a very significant effect on how much a cube of edged board weighs. This great dependence is due to the fact that water is present in large quantities in the cellular structure of freshly sawn wood, and if it is not dried properly, its rapid evaporation can lead to significant distortions in the geometric shape of the boards and bend them.
As a result, it can be argued that the weight of a cubic meter of edged board can be determined by the type of wood, classifying it into one of the categories.
Light wood species include pine, fir and other conifers, as well as poplar. Their average density, that is, the weight of a cubic meter fluctuates around the figure of 500 kilograms.
Medium species - a cubic meter of ash, beech, birch - weighs about 650 kilograms.
Heavy species, such as oak or hornbeam, have a density of more than 750 kilograms per cubic meter.
Answer from 22 answers[guru]
Hello! Here is a selection of topics with answers to your question: How much does 1 cubic meter weigh? m of pine board?
Answer from Irina Saburova[newbie]
IN different companies the price may vary significantly. The main thing is not to miss the issue of quality in the pursuit of cheapness. Here is the link by the way, excellent price/quality ratio. Plus they offer discounts if you buy a large volume and give very good advice if you are not very well versed in the matter.
Answer from Alexander Lestorg[newbie]
The Lestorg company is a manufacturer of lumber. Edged boards occupy a significant segment in the total volume of products produced by our company, since construction material from natural wood is in maximum demand in construction industry. We offer to buy edged board from the manufacturer at a competitive price.
1 m3 – 5000 RUR
link
Answer from Osipov Alexander[newbie]
Price for all sizes here link
22oa.ru
How much does a cube of pine weigh? | KtoiKak.com
People who are building their own house or cottage want to know how much 1 cube of pine weighs.
How much does a cube of natural moisture pine weigh?
1 cube of pine weighs 600-800 kg (depending on humidity)
- Dry – wood with a moisture content of 10-18%, which has undergone technological drying or has been stored (dried) for a long time in a warm, dry room;
- Air-dry – wood with a moisture content of 19-23%. This level of humidity is achieved when long-term storage wood under certain natural conditions, i.e. without application special technologies drying;
- Raw - wood with a moisture content of 24-45%, which is in the process of drying from a freshly cut state to equilibrium;
- Freshly cut and wet - wood with a moisture content of more than 45%, recently cut down or kept in water for a long time.
Now you know how much a cube of pine wood weighs and you can accurately calculate the required amount.
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