Pressed plywood: description of material, production technology and price

OSB plywood (OSB or OSB) is a completely new type of lumber, which appeared on the building materials market relatively recently, but has already won the trust of a large number of people. This is due to the fact that such material includes all the best qualities of wood and at the same time is devoid of almost all of its disadvantages. Next, we will consider the main characteristics of OSB plywood.

OSB boards are a new, lightweight, durable construction lumber with a long service life.

Why choose wood panels

Wood panels are materials made from natural wood with various additives: mineral binders, synthetic resins, etc. The result is products with high performance characteristics, specifically designed to solve certain technological problems. The appearance of wood-based panels on the construction market was driven by the desire to obtain a material that retains all the many advantages of natural wood, but at the same time is devoid of most of its disadvantages.

It is known that wood changes size and shape under the influence of changes in environmental temperature and humidity. Uneven removal of moisture leads to stress and cracking of wood. It is also susceptible to fire, insect damage and rotting. In addition, natural material is characterized by anisotropy, that is, a change in its mechanical characteristics for a number of reasons: depending on the direction of the fibers, breed, growth zone, presence and location of defects, etc.

Wood-based panels are free from almost all of these disadvantages, but they nevertheless retain the performance characteristics of natural wood. The technological features of production make it possible to produce them in different sizes, including in the form of large sheets, which makes it possible to get rid of another unpleasant feature of wood - the not always convenient “format” of the material. Wood boards are more accessible, including in cost. They are widely used in construction and are considered indispensable for some work. Let's take a closer look at each type of material.

Plywood is a wood-based material in the form of sheets consisting of pressed wood veneer plates tightly fastened together. They are glued together in such a way that the fibers of adjacent layers are mutually perpendicular. The minimum number of veneer sheets is 3, the maximum is 23 pieces. There are equal-layer plywood, where the thickness of the veneer plates is the same, and unequal-layer plywood, which has wider middle layers.

Depending on the manufacturing technology, plywood is distinguished:

1. Peeled. During the production process, wood is cut from a rotating log.
2. Sawn. The raw material used is sawn into thin, about 5 mm thick, strips.
3. Planing. Sliced ​​veneer up to 3.5 mm thick is used.

Depending on the type of wood used for the production of boards, plywood is distinguished:

1. Deciduous. It is made from alder, aspen, poplar, maple, but most often birch, which is distinguished by its increased strength and beautiful texture. Hardwood plywood is used in construction, decoration, furniture production, automotive industry, etc.
2. Coniferous. Made from coniferous trees. Raw materials naturally saturated with resins provide better moisture resistance of the material. In addition, coniferous wood boards have an attractive texture, are lightweight and quite durable. Widely used in construction and furniture production.
3. Combined. Made from both types of wood, it combines strength and moisture resistance, while maintaining an affordable price. Used in construction and furniture production.

There is another classification of plywood, dividing the material into several grades:

1. FSF or plywood with increased moisture resistance. It is produced using phenol-formaldehyde adhesive resins, which give the material special moisture resistance and biostability. The size of the boards is slightly inferior to other brands of plywood. The material has a class D4, which allows it to be used for outdoor use. It is also used for interior decoration of buildings, car interiors, street fencing, concrete formwork, etc.
2. FC or plywood with medium moisture resistance. In the process of gluing veneer, urea adhesives are used, which give the finished slab high strength, exceeding the strength of the original wood. However, the moisture resistance of such materials is low, the class does not exceed D3, so it cannot be used for outdoor work. The biostability of FC plywood is also insufficient; with prolonged moisture, fungi can begin to develop in it. The material also reacts to sudden temperature changes. Used for interior decoration and furniture production.
3. FB or bakelized plywood. The veneer plates are glued with bakelite varnish and synthetic resins, which allows the material to be used in fairly harsh weather conditions. Wood board is durable, has increased moisture resistance, fire resistance and wear resistance. Easily withstands sudden temperature changes. Used in construction, including exterior work, shipbuilding and automotive applications.
4. FBA. Material glued with natural albumin casein glue. This impregnation makes plywood non-moisture resistant, which significantly limits its scope of application. The main advantage of the FBA brand is its absolute environmental friendliness, since only natural ingredients are used in its production.
5. BS or aircraft grade plywood. The veneer is impregnated with alcohol-soluble bakelite glue, which gives the slabs special properties. The material is characterized by super strength, flexibility, high elasticity, resistance to aggressive environments, the effects of microorganisms and water resistance. Initially used exclusively in aircraft and shipbuilding. Today it is also used in construction, but is not very common due to its relatively high cost.
6. BV. In its manufacture, water-soluble bakelite glue is used. Has the same properties as BS, excluding moisture resistance.
7. Laminated. Lined on one or both sides with a special paper-resin coating. It is resistant to destruction and corrosion, is resistant to abrasion and prevents moisture from entering the material. In addition, the decorative coating can imitate any materials and textures. Used for interior decoration, furniture production, etc.

All plywood, according to existing standards, is divided into five grades, designated by the letter E or numbers from one to four. The criterion in this classification is the general appearance, the presence of acceptable processing defects and defects. Grade E or elite is completely devoid of them, all others allow a certain number of flaws. The grade of plywood is most often indicated by two symbols separated by a dividing line. The first indicates the grade of the front layer, and the second - the back layer.

Despite the variety of types of plywood, they all have common advantages:

1. Wear resistance and strength. Design features suggest high wear resistance and strength of the material, due to the different directions of fibers in the veneer layers that make up the slab.
2. Ease of use. Light weight makes installation easier. In addition, the material is easy to process. The structure of plywood allows it to be cut in any direction and in any place, which distinguishes the board from wood.
3. Cheap production. Solid wood is not necessarily used as a raw material for plywood; waste is minimal. All this significantly reduces the cost of the material.
4. Flexibility and shape stability. The plates are easily bent and take various shapes without cracks or deformations.
5. Retains heat well.

Among the significant disadvantages of plywood it should be noted:

1. Insufficient resistance to adverse environmental conditions, especially high humidity. Brands intended for outdoor use are more durable.
2. Design flaws. The structural features of the material make it vulnerable to moisture. Layers of wood easily absorb liquid and “carry” it deep into the plywood, which weakens the adhesive joints and destroys the wood.
3. Moderately toxic materials are used in the production of slabs. This is true for moisture-resistant plywood brands. The share of harmful substances is about 5% of the dry residue and decreases over time to almost zero.

The cost of the material varies greatly depending on the type of plywood, thickness, brand, etc. For example, the price of a 4 mm thick sheet of the second grade of the FK brand starts from 310 rubles, while a board with the same characteristics, but the FSF brand will cost from 670 rubles .

Differences from other fuels

In terms of combustion mode, pressed sawdust is no different from conventional firewood or coal. But in structure they are closer to the second option, since they do not have capillaries that penetrate all the wood, so the decomposition occurs somewhat more slowly.

And sawdust is not capable of crackling comfortably. But with them you don’t have to worry about flying sparks and rebounding embers.

Chipboards

Particleboard is a composite sheet material, the production of which uses a mixture of sawdust and a binder. Wood chips are combined with urea-formaldehyde and phenol-formaldehyde resins, thoroughly mixed and processed under high temperature and pressure. The binding components activated under such conditions reliably connect sawdust, which makes it possible to produce slabs of various thicknesses. High pressure makes the chipboard more uniform and dense.

There are several classifications of particle board:

1. By variety. The main criterion for separation is the appearance of the slab. The presence or absence of chips, cracks, stains, depressions and protrusions is taken into account. Material of grade 1 is distinguished by a minimal number of defects, grade 2 allows large flaws on the surface, and products without grade have even more significant damage.
2. By the number of layers. Single, three and multi-layer plates are available.
3. According to the degree of surface treatment. Unsanded and sanded wood boards are produced. In addition, there are laminated chipboards, on which a melamine film is applied under conditions of high temperature and high pressure, and laminated boards with a decorative coating glued under high pressure.
4. According to the level of formaldehyde emission. There are: class E1 material, which contains less than 10 mg of the substance per 100 g of dry board, and class E2 boards, in which the formaldehyde content ranges from 10 to 30 mg.
5. By brand. The separation criteria are indicators of water resistance, bending strength, susceptibility to deformation and warping. There are two brands: P-A, which has the best characteristics, and P-B.
6. According to the pressing method. There are different types of extrusion and flat pressing plates.
7. By density. Low density chipboard is produced, which is less than 550 kg/m 3 , medium density, the value of which varies from 550-750 kg/m 3 and high density, which is more than 750 kg/m 3 .
8. According to the type of outer layer. Slabs are produced with a coarse-grained surface, fine-grained, which can be faced with polymer materials, and regular, with possible veneer coating.

The main advantages of particle boards are:

1. High strength, superior to that of natural wood.
2. Good water resistance due to the presence of synthetic resins in the material.
3. Easy to process. The slabs are easy to cut, paint and glue.
4. Affordable price.

The most noticeable disadvantage of chipboard is the presence of formaldehyde in its composition, a very toxic substance. When choosing slabs, you should pay special attention to the formaldehyde emission class. In addition, the material is quite fragile, which does not allow for fine processing of parts, and does not hold screws and nails well, especially when tightening repeatedly.

The scope of application of chipboard is very wide. They are used for the construction of fences and collapsible structures, cladding and arrangement of roofs and walls, production of underlays for floor coverings, floors, wall panels, finishing and decoration, removable formwork, as well as in the production of furniture, packaging, shelving, etc. Cost slabs start from 650 rubles. for a standard sheet.

Range. Plywood or OSB.

There are not many varieties of OSB. Apart from the brand, you can only choose a smooth/rough surface, a straight/grooved edge – that’s all.

It's more interesting with plywood. For special loads and high humidity (reusable formwork, for example), you can buy FOF laminated plywood; for cladding in rooms, you can order the FK brand made of birch. On the street, of course, FSF is purchased. If we need decorativeness, we take high-grade sanded sheets, and if we want to make inexpensive rough cladding, we buy 4/4 or 3/4 grade with an unsanded outer layer of veneer.

This is how plywood is made

Cement particle boards

Cement particle boards are a relatively new sheet large-format building material, which includes thin wood shavings, Portland cement and special chemical additives. During the production process, the components are mixed, after which the structure of the slab is formed from them. Larger fractions are placed inside, and smaller ones are placed outside. This multi-layering provides the material with special strength. The cement-bonded particleboard mass is pressed, resulting in a smooth multilayer slab.

Types of DSP include:

1. Fibrolite. Long-fiber shavings, the so-called wood wool, are used to make boards. The material is molded in the form of heat-insulating plates with a height of 3-15 cm and a density of 300-500 kg/m3. This coating is quite soft, easy to process, and is highly bioresistant. It is used for internal insulation of brick and stone floors and walls, as well as for filling panel and frame structures.
2. Arbolit. In its production, small shavings and sawdust are used. Material density 400-850 kg/m3. The plates have good heat-saving characteristics. They are used as thermal insulation, as well as structural materials: panels, wall blocks, reinforced slabs of coverings and floors, etc. Arbolite slabs used as a material for external walls must be covered with a protective finishing layer.
3. Xylolite. It consists of lightweight concrete with sawdust on a magnesium binder. There is a cast and slab variety of material. It is characterized by high abrasion resistance, strength and resistance to shock loads. To obtain the desired color, alkali-resistant powder pigments are added to its composition. It is used as a material for the manufacture of floors, which in their characteristics are not inferior to stone ones, but are much superior to them in thermal insulation.

Cement particle boards have a number of advantages:

1. High strength due to the multilayer structure of the material.
2. Low cost.
3. Good frost resistance, water-repellent and fire-resistant properties.
4. Environmentally friendly, since the material contains no toxic substances.
5. High sound insulation characteristics.
6. Easy to process; slabs can be cut with hand tools.
7. Possibility of using different types of finishing: wallpapering, painting, plastering or ceramic tiling.
8. Resistance to microorganisms and insects.
9. Long service life, which is more than 50 years.

The disadvantage of CBPB is considered to be its high density, reaching up to 1.4 t/m 3, which makes the material quite heavy. A square meter of cement bonded particle board weighs about 14.5 kg, which makes installation difficult. In addition, the bending strength of the plate is low and it can break. At the same time, the material is very resistant to longitudinal deformations, which makes it indispensable for strengthening house frames.

The scope of application of DSP is very wide. They are used to insulate buildings, for their internal and external cladding, in the manufacture of frame structures and various moisture-resistant partitions, and in the production of sandwich panels. They can be used for interior decoration of walls and floors, as well as for the manufacture of permanent and removable formwork, such as roofing or as window sills. The cost of standard size DSP sheets starts from 750 rubles.

Material for making braces

To make briquettes, all kinds of production waste are used, which otherwise would quickly end up in a landfill, slowly decomposing under natural conditions.

The sawdust, which will soon become an excellent fuel, is further crushed and, if necessary, dried. With the help of special presses, the mass is transformed into a single whole, completely ready for use.

Absolutely safe elements are used as binding elements; some manufacturers produce their products without adhesive filling.

Sometimes briquettes are subjected to additional firing, but the absence of this action does not in any way affect the ability to generate heat and is not some kind of know-how or deviation from invented technologies.

Oriented Strand Boards

Oriented strand board is a modern material used in construction and finishing. It consists of about 90% wood in the form of shavings and chips, bound together with waterproof synthetic resins. Each slab is formed by three or four layers of chips pressed under high temperatures and pressure, the length of which reaches 15 cm. The peculiarity of the material is that the direction of the chips in each layer is different, this allows the slabs to acquire special strength.

The industry produces several types of oriented strand boards:

1. OSB-1 has low moisture resistance and strength. They are used for interior work and for furniture production.
2. OSB-2 is characterized by low moisture resistance and high strength. They have proven themselves well as floors, load-bearing structures and internal partitions.
3. OSB-3 is characterized by high moisture resistance and the same strength, therefore it is optimal for outdoor work.
4. OSB-4 has high moisture resistance and ultra-high strength, which allows them to be used as load-bearing elements, roofs and walls.

In addition, oriented strand boards with a laminated or varnished surface are produced, which are indispensable, for example, for the repeated production of formwork. Slabs with tongue-and-groove joints applied to the ends on two or four sides are also produced.

The main advantages of OSB are:

1. High strength and resistance to all kinds of damage, due to the design features of the material.
2. Long service life, more than 50 years, provided that tightness is maintained.
3. Easy to install and handle. The relatively light weight of the slabs allows you to do without additional equipment when installing them on the roof or walls. The material is easy to saw, drill, etc. Chips, cracks and unevenness are practically not formed.
4. Good resistance to various biological influences and air humidity.
5. Affordable price.
6. Provide good sound insulation and heat retention.
7. The large sheet format allows the construction of a structure with a minimum number of joints.

The main disadvantage of the material is the presence of toxic substances in its composition. To avoid troubles when purchasing, you should check the environmental class of the board and never use OSB intended for outdoor use for purposes other than its intended purpose. In addition, the slabs are flammable and require preparatory measures before decorative finishing. If there is no tightness, they can begin to absorb water and swell, as a result of which the structure becomes deformed and loses its strength characteristics.

Oriented strand boards are used for cladding ceilings, walls and floors, arranging stairs and floors, producing sandwich panels, constructing frame houses, and covering roofs. They are used when carrying out auxiliary work, such as installation of scaffolding, formwork, etc., for the construction of auxiliary buildings, fences, street structures and in the form of structural elements of furniture. The cost of material from European manufacturers starts from 800 rubles. per sheet.

Which is better for shaping the floor?

The data in the table suggests that plywood copes better with high humidity and damage. This material is also more environmentally friendly than OSB sheets, however, its cost is higher. OSB holds the geometry of the sheet noticeably better; the floor may visually appear more even. In children's rooms, it is recommended to use plywood from a safety point of view. In general, both materials can be used for flooring. With the correct installation technology on concrete or joists, both plywood and OSB will create a smooth and durable coating for further finishing.

Fiberboards

Fiberboard is a material consisting of a fibrous mass obtained from wood or other cellulose-containing plant fibers, synthetic polymer resins, fillers, special additives and water. Fibreboard is produced in two main ways: dry, with the addition of synthetic resins to the crushed fibers, and wet, without the addition of chemical binders.

The method of formation and processing determines the division of fiberboards into several types.

Super hard

The density of this group of materials reaches 1100 kg/m3. They are characterized by high bending and tensile strength. All this allows the use of super-hard slabs in the manufacture of panel exterior and balcony doors, for parts of built-in furniture and as a structural and thermal insulation material for flooring. There are brands of this variety:

1. ST - slabs of increased hardness, the front surface is not refined.
2. ST-S - increased hardness, the front layer is made using fine wood pulp.

Solid

The density of these materials is about 850 kg/m3, and they are also quite strong in bending and stretching. Several brands of solid fiberboard are available:

1. T - sheets with an untreated surface.
2. T-S - the front side is made of fine wood pulp.
3. T-P - the front side is tinted.
4. T-SP - the front layer of fine wood pulp is tinted during the production process.
5. Т-В - increased moisture resistance and untreated front surface.
6. T-SV - increased moisture resistance, the front surface is made of fine wood pulp.

The first four types are further divided into two quality groups, A and B. The division criterion is the level of physical and mechanical characteristics. Group A is slightly superior in its parameters to group B. To give the slabs a more attractive appearance, they can be subjected to various finishing options. The material is painted with polyvinyl acetate water-based paints, which makes the surface matte, or with enamels based on synthetic resins to obtain a semi-matte or mirror surface. In addition, to imitate the boards, they can be laminated with synthetic films with textured paper inside.

Solid matte fiberboard is used for cladding ceilings and walls in rooms with normal operating conditions. Glossy and semi-matte - as decoration for the walls of bathrooms, kitchens, panel doors. Special perforated panels can be used for cladding ceilings, which improves their sound insulation properties. Also, material of the T-SV and TV brands can be used for covering floors and in the construction of external panel doors and balcony doors.

Semi-solid

The material is better known as MDF. This is an abbreviation of the name "medium density fibreboard" in English. It is made by dry pressing with the addition of urea resins modified with melamine, which significantly reduces formaldehyde emissions and makes them more environmentally friendly. During the production process, MDF is given special properties: water resistance, fire resistance and biostability. The boards are durable, this indicator is 2 times higher than that of fiberboard. The density of the material ranges from 600 to 800 kg/m3.

MDF is most often sold without coating, with the exception of facade options, which requires additional finishing costs. The slabs are used for interior decoration in the form of laminated flooring, wall panels, and also in the production of furniture. This is due to the low cost of MDF, its uniform structure and ease of processing. The slabs lend themselves well to sawing, drilling, milling, etc.

Using pressed sawdust

The main uses of briquettes are:

• Heating of residential and non-residential buildings;
• Ignition of decorative stoves and fireplaces;
• Use as fuel for picnics;
• Cooking in barbecues and tandoors;
• Heating baths and saunas.

An unusual way of using it is to insulate the walls and ceilings of houses, but in this case it is recommended to use ordinary sawdust.

Tips for use

In principle, there is no particular difference between the use of conventional solid fuel and sawdust briquettes, but experts give some advice on the use of more modern material:

• For fireplaces and stone stoves, the active burning time should not exceed two hours, otherwise the masonry may be destroyed. But there are no restrictions on smoldering, which is often used by owners of such heating systems. But the pipes become more clogged, so you will have to clean the chimneys at least twice a year.
• You will also have to check the chimney more often when using briquettes made from sawdust from coniferous trees or fuel with a high bark content. Such sawdust retains much more resins, which, during combustion, settle on the surface of chimneys.
• Sawdust from soft woods takes up more volume, but has less heat output, so it is recommended to buy them mainly for summer use, when a large amount of heat is not very important for creating comfortable conditions.

Recruitment

At the initial stage or in small-scale production, you can assemble the pallets yourself. The process does not require special technological knowledge, so it will not cause difficulties. One person per day can collect 70–90 products. If delivery volumes increase, you can hire 1–2 additional people.

When using an automatic line for the production of pallets, the staff of workers should be 9–10 people:

• 3–4 masters for assembling products;
• 5–6 workers to carry out trimming, sorting and loading and unloading operations.

This number of personnel can produce 500–550 pallets per day. The simple technological process of making pallets allows you to hire low-skilled workers.