Press for osb. Types of OSB boards

OSB - OSB (Oriented Strand Board) - modern material for modern construction. OSB equipment works around the clock. Manufacturers of equipment for the production of OSB boards indicate capacity at the rate of 334 days per year, 31 days for scheduled preventive maintenance.

A fundamentally new type of woody chip materials became the recently appeared oriented strand board OSB (OSB boards). This material retained the best qualities natural wood and is devoid of the disadvantages of analogues - plywood or chipboard.

Oriented strand board is a three-layer material made of "wood wool" - elongated (6-9 cm) wood chips conifers. The main feature of OSB boards is the different orientation of the chips: in the upper and lower layers, the chips are located along the length of the entire board, and in the middle layer - perpendicular to the covering layers.

It is the multidirectionality of the fibers in the layers that ensures the exceptionally high mechanical strength of OSB boards - it is 3 times higher than that of plywood or chipboard. At the same time, the flexibility inherent in wood materials, is saved.

All three layers are impregnated with waterproof waxes and resins and pressed into a single whole under the action of high pressure and temperature. The same large sizes of chips and the modern pressing method ensure the uniformity of the material throughout the slab, the absence of voids and cracks in its thickness and chips along the edges.

Small waste chips are removed during production, due to this, a significant reduction in the amount of connecting adhesives in the composition of OSB boards has been achieved - only 2-3%. OSB is almost completely purely wood material. At the same time, OSB boards are devoid of the shortcomings of pure wood - they are not subject to rotting, fungal attack, and are not combustible. The most important property OSB boards - boards have almost zero hygroscopicity. This property underlies the use of oriented strand boards in roof construction. To date, no the best material for the base for roofing. According to the degree of hygroscopicity and strength, OSB is divided into groups that determine the scope of a particular type of material. The use of OSB boards is based on their excellent consumer qualities - strength without loss of flexibility, moisture resistance, lightness.

First of all, these are all branches of construction. The device of a continuous crate for all types of roofing and floor coverings, wall and ceiling cladding, including decorative (OSB does not emit formaldehyde into the air), the creation of a removable formwork. OSB material is indispensable in attic construction.

In North America, OSB boards are a constructive basis for all cottage construction, they act as a frame in any building element. The exceptional strength of the material, its environmental friendliness, durability of OSB structures at a low price make the material a leader in its market segment.

are divided into groups that determine the scope of a particular type of material. The use of OSB boards is based on their excellent consumer qualities - strength without loss of flexibility, moisture resistance, lightness. First of all, these are all construction industries.

The device of a continuous crate for all types of roofing and floor coverings, wall and ceiling cladding, including decorative (OSB does not emit formaldehyde into the air), the creation of a removable formwork.

• OSB has a homogeneous internal structure and both surfaces are of the same quality.
• OSB contains over 90% wood
• OSB-2 (OSB2) - conventional oriented strand board
• OSB-3 (OSB3) - moisture resistant oriented strand board

Oriented strand board or OSB board is another way to make smart use of non-commercial wood. This composite material was invented in Canada, and now it is in demand everywhere in construction, in the manufacture of furniture. The proposed article will introduce you to the types and OSB characteristics will talk about their use.

Slabs are produced by pressing waste wood 6-9 cm long and 0.5 to 0.7 mm thick coniferous and hardwood. At the same time, conifers are used by European manufacturers, and in America and Canada - deciduous. The secret of OSB durability lies in the way the inventors arranged the wood chips in 3 or 4 layers of material:

• in top layer it has a longitudinal, with respect to the axis of the plate, orientation;
• on average - transverse, at an angle of 90 degrees to the upper and lower layers;
• chips in the lower layer are located the same way as in the upper one.

Simplified production technology looks like this:

1. A wood carpet is formed on special presses under high pressure and at high temperature.
2. Impregnate for bonding with phenol and formaldehyde resins, waxes.
3. Cut into boards of standard sizes.

Why is this stuff so popular?

Every year, the supply of OSB boards is increasing due to growing demand. Why are these three-layer boards gaining such popularity? The answer is obvious:

• they are visually attractive;
• compared to chipboard, it is 2.5 times stronger;
• do not delaminate, there are no voids, knots inside, therefore they are also called “improved wood”;
• no special tools are required, it is processed easily with ordinary carpentry tools;
• hold nails, screws are very strong, because contains adhesive additives;
• they are light in weight, therefore, when used for frame construction, a powerful foundation is not needed;
• retain strength characteristics even after a daily stay in water;
• environmentally friendly, since the percentage of formaldehyde resins in the composition is negligible;
• have excellent heat and sound insulation properties;
• resistant to chemicals and mechanical damage;
• have antiseptic properties due to the presence of special additives in the composition;
• designed for long term use.

The list of QSB advantages does not end there, the following qualities can also be included in this list:

• small tolerances;
• high density;
• perfect edge processing;
• homogeneity of properties at any point;
• increased fire resistance.

Types of OSB boards

The industry produces 4 types of oriented strand boards:

1. OSB-1 - used for the manufacture of unloaded elements of furniture, packaging, wall cladding indoors under conditions low humidity.
2. OSB-2 - recommended for dry rooms in the manufacture of loaded structures.
3. OSB-3 - withstands high humidity and heavy loads. It is applied as the basis under a flexible tile in frame construction, for floors and ceilings, for the device of stairs.
4. OSB-4 - structures are made that are subjected to significant mechanical loads in combination with high humidity. It is used for the manufacture of repeatedly used formwork, etc.

The color scheme of the plates is in the range of light yellow-brown and depends on the species used for manufacturing, wood, pressing technology, type of resins used for bonding.

Characteristics of OSB boards

OSB boards must comply with the European standard EN-300, which puts forward the following requirements regarding humidity:

As for the strength characteristics, they are as follows:

From the characteristics given on the OSB board, it follows:

• OSB-4 has the highest moisture resistance and super strength, suitable for extreme conditions;
• OSB-3 best option for construction. This is an OSB plate, the price of which is significantly lower than that of OSB-4.

Dimensions of OSB boards

The industry produces plates with the following dimensions:

• 122x244 cm;
• 122x366 cm;
• 125x600 cm;
• 125x250 cm;
• 125x370 cm.

You should be aware that OSB boards, which are the same size, can vary significantly in weight due to different thicknesses. Therefore, they are classified according to this parameter. It ranges from 0.8 to 2.6 cm. At the same time:

1. Sheets up to 1.6 cm thick are mainly used for wall cladding, wood flooring, and underlayment for soft roofing.
2. Where a significant load is expected, estimated in hundreds of kg per 1 sq. m, the thickness of the OSB plates is selected above 16 mm. Of these, the floor is laid, load-bearing roof structures are performed.

Features of processing OSB boards

When processing OSB, the same tools are used as for working with solid wood, but preference should be given to carbide drills, saws, cutters, nozzles. Distinctive features work with OSB is as follows:

1. The feed rate is slightly less than that used for processing natural wood.
2. It is recommended to fix the sheet when working with it with ring and spiral nails, and it is better not to use smooth nails.
3. When arranging load-bearing structures from OSB, you should choose fasteners from a material that does not rust.
4. Fulfilling OSB installation, it is necessary to provide gaps between the plates for insurance. This will protect them from deformation when volumetric characteristics change in case the humidity changes.

OSB board. Application

A building material such as OSB board, the use of which facilitates and speeds up the implementation of many construction works, is used when erecting:

• frame structures;
• prefabricated interior partitions;
• floor coverings;
• formwork;
• temporary buildings;
• scaffolding;
• garden houses, gazebos;
• solid bases for some roofing materials.

In addition, the plates are used for the manufacture of furniture, decorative elements interior.

OSB installation is not possible without prior preparation:

• when installing the floor, lags are installed;
• under the roof of OSB, a crate is performed;
• when cladding walls, a frame is required, for the set of which special profiles are used.

How much does osb board cost

The cost of OSB boards is influenced by many factors. We name the main ones:

• manufacturer. So, domestic plates are several times cheaper than European and American ones;
• brand;
• characteristics.

In addition, there is a classification of OSB boards into 2 categories:

• tongue-and-groove, which are used mainly for flooring;
• plates with a standard edge.

Depending on the technology by which OSB boards were made, the price also changes.

Overview of OSB board manufacturers

The main output of OSB boards falls on the USA, Canada, European countries, but there are also domestic manufacturers whose products are represented on the market of wood-based products.

OSB from Novovyatsky ski plant

This manufacturer produces OSB-3 oriented strand boards from coniferous chips 0.6-0.9 cm long. The characteristics are as follows:

1. Density - 700 kg per 1 cu. m.
2. No formaldehyde smell, which is sometimes present in low-quality products.
3. Dimensions:

• 1850x2500x6;
• 1850x2500x9;
• 1850x2500x12;
• 1850x2500x18;
• 600x2500x9;
• 600x2500x12.

OSB by Hillman

Another domestic manufacturer— Hill Man Co., Ltd. The products of this company belong to the premium class. The peculiarity of the plates is that large birch shavings were used for their production. It allowed:

• achieve high physical and mechanical performance;
• obtain a certificate for the compliance of plates with European standards.

OSB-3 plate size:

• width - 1.25 m;
• length - 2.5 m;
• thickness - 0.9 cm.

Manufacturer Norbord (Norbord) from Canada

Slabs measuring 2.44x1.22 m, which are produced by the Canadian manufacturer Norbord from softwood, are distinguished by:

• minimum moisture absorption;
• maximum rigidity;
• resistance to various atmospheric influences.

Their cost, of course, is higher than that of OSB from Russian manufacturers.

Oriented flat strand board from the Swiss KRONO Group

The KRONO group of companies unites such European manufacturers as Kronospan, Kronopol, Kronosta and is managed by Kronotex GmbH. Enterprises are located in Bulgaria, Czech Republic, Romania, Lithuania, Poland. German specialists strictly ensure that European standards are observed in these countries, therefore:

• the quality of the boards complies with the EN 300 "OSB" standard;
• OSB has a stable geometry;
• the state of the surface of the plates is approaching the finish;
• is guaranteed for 25 years.

The standard size of plates from these companies is 2.5x1.25 m.

OSB boards CONSMOS from China

On the construction market OSB boards from Chinese manufacturers are often found. The most popular among them are plates with the CONSMOS marking. They differ:

• very democratic price;
• acceptable quality;
• wide selection of different varieties.

The sheet sizes are as follows:

• thickness - 6, 8, 9, 10, 11, 12, 15, 18, 21, 22, 25-30 mm;
• dimensions - 1220 × 2440 mm / 1250 × 2500 mm.

As can be seen from the above, oriented strand boards are a reliable, durable, lightweight material, many times cheaper than natural wood, so the demand for it will only increase.

About where the OSB plate is used, a video with specific examples:

wood composites

From the tree family composite materials in Russia are produced and best known: plywood, chipboard ( particle boards), MDF, glued laminated lumber and LVL veneer lumber.

OSB (Oriented Strand Board) also belongs to the class of wood composites. Today, OSB is one of the most advanced wood composite materials and is considered the most promising and versatile wood building material.

OSB is relatively new structural material. OSB production technology was born as a result of the development of the technology for the production of so-called wafer boards in Canada. industrial production OSB was started in the early 80s of the last century. Due to various economic and raw material reasons, the volumes of production and consumption of this material today vary greatly in various countries peace. The highest growth rate of the OSB market over the past ten years is observed in North America. If in 1990 the consumption of boards there was about 6.8 million m3, then by 2003 it had grown to 22 million m3 per year.

Similar growth rates are now observed in the European market, where OSB consumption has already exceeded 3 million m 3 per year and continues to grow. South America consumes about 500,000 m 3 per year of oriented strand board. China and Japan are also increasing their production of this material, but production capacity in Asian countries is still relatively small - the market there is mainly sold board imported from Canada.

Current situation with OSB in Russia

In Russia there is a very interesting situation. Neither in our country, nor in the CIS countries, there is not a single plant for the production of oriented strand boards. At the same time, the Russian OSB market is developing quite dynamically. Application of new construction technologies, the emergence of new building materials, as well as European board manufacturers and importers, are actively stimulating this development. According to various estimates, the capacity of the Russian market is already estimated at the level of 120,000–150,000 m 3 per year.

Russia has huge reserves of non-commercial timber, which does not find any use and simply disappears in the cutting areas. According to experts, Russia could produce OSB at one of the lowest cost prices in the world.

What's stopping us?

What prevents the appearance in Russia own production OSB?

To date, one of the main deterrents are significant financial risks in such a project. OSB technology is now one of the most high-tech in the production of wood-based panels. This affects the amount of investment that needs to be attracted to the project. When ordering equipment from the largest European suppliers, such as Metso, Dieffenbacher and Siempelkamp, ​​who offer a complete turnkey supply of a production line, the amount of capital investment becomes so significant that the project will pay off in a reasonable time only with significant production capacities of the line. And the output of a plant of large and even medium capacity (at least 150,000–200,000 m 3 per year) with its products to the market, which consumes exactly the same amount, seems too risky. Commercial risks are also seen as too high.

The lack of production experience and competent specialists imposes additional risks when organizing the country's first plant for the production of OSB boards.

Another limiting factor, of course, is the lack of awareness of domestic investors and manufacturers about oriented strand board, about the technology and possibilities of their production, about the prospects for this product and possible markets for its sale. Very little technical information about OSB and equipment for its manufacture can be found in Russian.

True, it should be noted here that not so long ago in Russia, in St. Petersburg, the joint Canadian-Russian engineering group Wood Processing Consulting Services began its activities, which is actively engaged in popularizing OSB boards and promoting their manufacturing technologies among Russian industrialists.

The concept of creating a low-capacity OSB plant

The problems that prevent Russia from starting OSB production are quite obvious, therefore, last year, WPC Services engineers and analysts, together with IMS-Engineering, completed the development of a low-capacity OSB plant concept (65,000–70,000 m 3 per year), adapted specifically for Russian conditions. I would like to elaborate on this interesting project.

The main goal in the development of the project was to reduce the amount of necessary investments and optimize capital investments in such a way that the payback period for the project of the first Russian OSB plant did not exceed 5 years. Such a payback period in Russia is considered optimal for projects related to woodworking.

The developed concept was based on the joint use of imported equipment and equipment that can be produced at Russian machine-building plants. The bottom line is to import from abroad only the most complex, key equipment in technological process, such as a chipper, chip mixers, a press, etc. Less complex equipment, GTO pools, chip sorting, supporting metal structures, etc., should be designed and manufactured at a Russian plant under the direct supervision of our specialists. The time for the full implementation of such a project is 14-18 months, depending on the specific conditions of the Russian customer.

OSB production technology

According to the engineers, when developing the low-capacity OSB plant project, they faced the following tasks:

• use the most simple and proven technology for the production of OSB boards;
• ensure maximum reliability and efficiency of the equipment;
• ensure optimal utilization of raw materials and components;
• provide a flexible layout of the production line, which would allow the use of existing buildings and buildings.

The technology implemented in the project makes it possible to produce boards of OSB/3 quality, i.e. moisture-resistant boards for structural, building application. The possibility of a simple modification of the technology is provided for its application in all major climatic zones Russian Federation.

Consider the essence of the technology implemented in the project.

In the previous issue of the journal, we already wrote that almost any available wood can be used for the production of OSB: thinner wood, wood from fast-growing plantations, top parts of trunks with a diameter of 5 cm or more, as well as low-grade and substandard wood (see PPI No. 9 (31) 2005). At the same time, it is desirable to use round timber. Research was carried out on the possibility of using waste from plywood and sawmill industries. But when using such raw materials, the chip yield desired faction too low. At the next stage of production most of wood in this case is screened for burning. For the same reason, it is recommended to carry out a preliminary hydrothermal treatment of wood, especially in winter conditions. Frozen, as well as logs of low humidity, which have lain on the exchange for a long time, give too much small chips, and not chips of the right size.

Coniferous, softwoods and hardwoods medium density are most suitable for the production of oriented strand boards. Pine, aspen and poplar are considered to be the main types of wood in the production of OSB. These species are widespread in Russia, therefore, 50% pine and 50% aspen were taken as initial data on the species composition of raw materials. The length of the logs at the entrance was taken equal to 2.6 m, the diameter - from 50 to 400 mm (with an average estimated diameter of the logs - 150 mm), the moisture content of the wood entering the plant - in the range from 50-120%.

So, wood raw materials arrive at the plant site by railway or vehicles. Logs with a length of 2.6 m are stored and stored at the raw materials exchange. From there, with the help of jaw loaders, they are delivered to the input reservoir of the GTO pool (hydrothermal treatment). For the production of chips with the desired geometric parameters (length - 60-150 mm, width - 6-40 mm, thickness - 0.5-0.9 mm), unbarked logs must be preheated in pools. This is especially important in winter time and when working with hardwoods. Preliminary hydrothermal processing of raw materials significantly improves the quality and useful output conditioned chips obtained on a chipper. In addition, TRP extends the life of the chipper disc. Canadian engineers have developed a special design of the pools. They are through-type, self-cleaning, heated by thermal oil radiators. Skidding chains keep the entire loaded volume of wood in the water, preventing the logs from floating up. In the pool, the logs are thawed for a predetermined amount of time, and then one by one they are removed and transported by a log hauler to the chain feed conveyor of the debarker. A chain conveyor feeds logs sequentially to a high-performance rotary debarker.

The feeding conveyor of the debarker is designed in such a way that waste and small chips fall into special storage bins. In the future, these wastes are processed by the shredder into fuel for the boiler house.

Thus, only whole logs suitable for processing are fed further into the debarker. Estimated wood debarking efficiency at maximum performance OSB line is 99.5%.

By the way, it should be noted that the technology implemented in the project is completely waste-free and energy-sufficient: all thermal energy, necessary for technological needs, is produced here, at the plant, from the remains of wood.

The debarked logs are delivered to a specially designed debarker output conveyor. After that, the logs pass through a metal detector. Logs containing metal inclusions are automatically marked and rejected - removed from the stream. The good logs are pushed off the conveyor onto the crosscutting table, where they are cut into 860 mm long logs. The latter enter the inclined accumulative conveyor of the chipper and then one by one are fed into the chipper (for more details on the OSB chip production technology, see the next issue of the LPI). The disc chipper produces chips in a length to width ratio ranging from 4:1 to 6:1.

The wet chips leaving the chipper enter the raw chip hopper inlet conveyor. Then it is transported to the raw chip bin for accumulation and further dosed feeding to a single-pass drying plant. In the production of OSB, single-pass or double-pass dryers are used. Single pass dryers run on more than low temperatures thermal agent (300−450°C), but their drying cycle is longer than that of two-pass. The main advantages of single pass drum dryers are: Significantly lower emissions of volatile organic compounds, the chips in them are less damaged, and at lower drying temperatures there is less risk of fire. Purified flue gases from the boiler house are used as a heat agent in such dryers.

Thus, raw chips are dosed from the raw chip hopper directly into the single-pass drum dryer. Hot gases coming from the boiler house create the necessary temperature for drying chips.

Dry shavings at the outlet of the dryer are transferred by pneumatic transport (air flow) to the main storage cyclone. Here she separates from air flow and small wood particles. Small particles, in turn, are carried away by the air flow further and fall into secondary cyclones, where they settle. The spent and cooled air is released into the atmosphere.

dried shavings through Switchgear from the cyclone it is sent further for sorting or dumped into the fire compartment (in the event of a fire signal in the dryer from the explosion and fire safety system).

Through the inlet dosing device, the chips enter the rotary type sorting machine. At this stage, small particles and wood dust are finally removed from the chip stream. Suitable chips are divided into two streams and fed to the input conveyors of the outer and inner layer chip bins. Conveyors transport the chips to the appropriate bins.

Before getting into the mixers, the chips accumulate in the dry chip bins of the external and inner layers. The volume of these bins is designed to ensure the smooth operation of the entire production line. They are similar in design to wet chip bins. The feed rate of the material from the hoppers is adjusted depending on the parameters of the chip mat forming line.

From the hoppers, dry chips are fed through conveyor scales (an element of the dosing device) to the mixers. Belt scales also set the flow rate of resin and paraffin, which are fed into the mixers in a given ratio, depending on the flow of chips.

Liquid resin storage tanks are located in close proximity to the mixers. There are four in total: two for resin on the outer layer of the boards, two for resin on the inner layer. From the tanks, the resin is fed through automated dispensers to the mixers.

In the production of OSB, phenol-formaldehyde resins (PF), melamine urea-formaldehyde (MUF), as well as isocyanate resins (PMDI) can be used. Based on these resins, a binder for waterproof boards is prepared. The project is designed to use liquid phenol-formaldehyde resin, as it is the cheapest and most commonly used type of binder for OSB.

Paraffin is delivered to the plant in liquid form and stored in large heated tanks. From the tanks through automated dispensers, it is fed into mixers, where it is sprayed through internal tubes. The tubes are also heated to prevent the paraffin in them from hardening.

On the output conveyors of the mixers, the chips are fed to the distribution device of the forming station. Further, with the help of distribution conveyors, it is delivered to the corresponding bunkers of the chip molding machines of the inner and outer layers. The forming and pressing system consists of forming stations, forming line and single span hot press. Note that a single-span press freely provides the design capacity of the plant (220 m 3 per day), and, moreover, it is much cheaper than the continuous press widely advertised now.

Three shaping machines - two for the outer layers and one for the inner layer (each equipped with one orienting head) - spread and level the resin chips on steel pallets continuously moving along the line. Built-in belt scales are located below the forming line and are designed to weigh carpet layers as they are formed.

The orienting heads of the outer layer molding machines align the chips parallel to the direction of movement of the molding line, while the inner layer molding machine head aligns them perpendicularly. The amount of chips coming from the hoppers of the molding machines is strictly controlled, since the volume and weight of the gummed chips of the inner and outer layers must be in a given proportion. This is essential to ensure compliance finished products specifications and standards.

An electromagnet and a metal detector are included in the molding line to detect and remove random metal inclusions.

The continuous chip mat formed in this way is cut with miter saws according to the specified width. Then circular saw the carpet is cut to length to the size of the hot press plates. The carpet scraps are pneumatically transported to the output conveyor of the inner layer chip mixer for reuse. If the carpet formed on the line does not meet the specified parameters, it is automatically removed from the forming conveyor before pressing. This process is controlled by a carpet rejection system. The rejected chip mat either goes back into the stream (to the inner layer mixer output conveyor) or is completely removed (if metal inclusions are detected, for example).

The prepared parts of the chip mat are sequentially fed into a single-span hot press. The press allows the production of OSB-boards in the thickness range from 6 to 40 mm. In the press, the plates are subjected to pressure and temperature. The control of the absence of air pockets and blisters in the plates at the outlet of the press is carried out by an ultrasonic sensor, which works in concert with the hydraulics of the press and is located on its discharge conveyor.

After pressing, oriented strand boards are cut around the perimeter. In this way, even edges of the slabs are formed, and the size of the master panels is set to them. After that, the master panels are weighed and, after cooling and technological exposure, they arrive at the final processing site.

It should be noted that the plates leaving the press, after being cut to the size of the master panel (2550 x 5005 mm), also pass through an air pocket detector and a thickness gauge. These two measuring devices control the quality of pressed boards, and their density is controlled by weighing.

At the final processing section, the master panels are cut into predetermined formats in accordance with the cutting chart. For this operation, a cutting center for board materials is used. The format of finished boards is 1250 x 2500 mm.

Finished slabs are fed to a stacker and stacked in 1250 x 2500 mm stacks. The stacks are then transported by forklifts to the packaging line, where they are splinted and transported to the finished product warehouse.

Table 1 shows how WPC Services engineers managed to reduce the project budget by more than 5 times. In the table, all production equipment is broken down in accordance with the technological zones where it is located. Of the total number of pieces of equipment in each zone, that part of the equipment that can be successfully manufactured at our factories has been singled out. As you can see, these are 54 technological modules. Estimated indicator of the Russian component technological equipment is 61%, the import component is 39%.

Resource requirement for OSB production

It is necessary to dwell in more detail on the resources necessary for organizing the production of oriented strand boards.

The covered area required to house the OSB production line is 18,500 m2. In addition, about 2-3 hectares of territory for the raw materials exchange will be required. At the plant, in our conditions, there should always be a “buffer” stock of raw materials for 3-4 months in advance.

The consumption of wood, binder and energy resources required for the production of 1 m 3 of OSB boards are shown in table 2. The indicated energy consumption is valid for the daily productivity of the line, equal to 220 m 3, with preliminary hydrothermal processing of raw materials and was calculated for the production of boards with a thickness of 12 mm, density 680 kg/m3.

findings

1. OSB technology is a technology for deep processing of wood. OSB is one of the most advanced wood composite materials. The technology considered in the article allows for a deeper and more rational use of timber reserves in Russia.
2. The growth rate of demand for OSB in the world market is one of the highest among wood-based panels. Russian market is also developing, there is a steady increase in demand for oriented strand board in our country, especially in large cities.
3. Despite the fact that OSB is a relatively new board material, it has already found quite a few areas of application. OSB is widely used both as a structural material in construction and simply as a wood composite with unique decorative properties (see LPI No. 9 (31) 2005).
4. The main application of OSB is in residential construction. Buildings and structures based on OSB require significantly lower financial costs and time for construction. The emergence of its own production of OSB stimulates the development of wooden housing construction, which, in turn, will reduce the cost of housing, increase its availability and reduce the severity of the housing problem in Russia.
5. OSB technology is perhaps the most best way use of non-commercial and low-grade wood in Russian conditions. We have all the prerequisites for creating our own OSB production.

Timber industry enterprises, except for edged lumber, periodically invent new ones. For example, chipboard was invented back in the 1940s in the United States, and by the end of the 20th century it became the most common material for furniture production, also widely used in construction. One of the materials of the new generation is OSB - oriented strand board (the abbreviation in Latin is also used - OSB, orientedstrandboard).

The first OSB board was produced in 1982 in Canada. OSB is a multilayer (3-4 layers) sheet consisting of relatively large wood chips glued with resins. Synthetic wax is also added to the OSB and boric acid. The name "oriented chip" comes from the gluing technology: the chips in the layers of the plate have an orientation (in the outer longitudinal, in the inner, respectively, transverse).

OSB is widely used for furniture, upholstery, packaging (boxes, etc.), load-bearing structures indoors; lacquered board is often used for design purposes, and laminated board is often used as the basis for reusable formwork in concrete work. In addition, there is a tongue-and-groove OSB (with machined tongue-and-groove ends) used for laying on a surface area.

As can be seen, the OSB is practically universal material, in addition, superior in mechanical parameters to existing analogues: it is stronger than chipboard (the strength of oriented strand board is approximately equal to softwood plywood); much more moisture resistant than chipboard and plywood; 25% better holds fasteners (screws, self-tapping screws, nails, etc.) than plywood. In addition, OSB is not susceptible to damage by insects and is easy to process, like its counterparts.

It would seem that the production of OSB is a gold mine. However, at present this material is not produced in Russia. The main OSB manufacturers are located in Canada, the USA and Europe, and about half of the boards in Russia are imported from China (corresponding quality, which has become the talk of the town). Accordingly, opening a business for the production of oriented strand board in our country will pay off any costs and expenses, because. domestic OSB will surpass the Chinese one in quality, but at the same time it will successfully compete with European and American in terms of price.

OSB production technology

OSB production can be conditionally divided into several technological stages. They are numbered and briefly described below.

1. Obtaining raw materials, which are raw round timber.

The most suitable wood in Russia for the production of OSB boards is aspen. However, it is possible to use conifers and even poplars (according to Chinese technology). Of course, for the production of OSB, mostly non-commercial wood is used, that is, trees of small diameter.

2. Hydrothermal treatment.

For hydrothermal treatment, special containers (tanks) with water are used. This process is necessary in order to equalize the temperature and moisture content of wood, which are different at the surface and inside, as well as soften it somewhat for further processing. The water temperature in the tanks is maintained at 30-40°C.

3. Debarking logs.

Debarking - the process of removing tree bark from logs. It is produced using rotary or drum debarkers.

4. Receiving chips.

For this, chipping machines are used, which are of two types: disk and ring. The disc machine is a little cheaper and easier to operate, but the ring machine is much more productive.

5. Chip drying.

The chips are dried in drum drying chambers(settings). There are one-, two- and three-pass installations. Sometimes conveyor dryers are also used, the disadvantage of which is the space they occupy.

6. Impregnation of chips with a binder.

This technological operation produced using special industrial mixers. The mixer is a simple cylindrical drum, which rotates at a given speed with the help of an electric motor and a gearbox. Paraffin, resin and other components are fed inside the drum.

7. Creation of a chip carpet with the help of molding machines.

The number of OSB layers depends on the number of molding machines, i.e. in production there should be at least 3-4 pieces. The device distributes the chips in an even layer and orients them in one direction. The resulting mass is called a chip carpet.

8. Pressing plates.

Hot presses take the layered particle mat, and the output is the finished product - oriented strand board.

9. Cutting plates according to the required format.

10. Packing.

Machinery and equipment for the production of OSB

The first thing you need is a debarker. Different in characteristics (power, type, performance, etc.) machines cost, of course, in different ways. But the approximate price level is as follows: from € 26,000 to 3,800 thousand rubles. for a unit. As you can see, the price range is considerable, however, the choice of debarking machines is very large and it is easy to choose the best option.

But high-quality chipping machines for the production of OSB have a more or less certain price: about 1300 thousand rubles. and higher. In this case, we are talking about the ring version, since the disk version is inferior to it in performance, and acquiring 2-3 such machines will still be more expensive than one ring one.

Each drying drum will cost about 460 thousand rubles, and a 6-bay hot press - 600 thousand rubles. Each molding machine costs 250 thousand rubles. - as already mentioned, there should be at least three of them. And each panel saw will cost from $28,400.

Of course, the above list of equipment for the production of OSB is incomplete: some additional and auxiliary units are missing: uncouplers and log haulers for extracting raw materials from hydrothermal treatment tanks; bunkers for storage and dosing of components; storage cyclones and automatic chip sorting lines - the following are considered to be ideal geometric dimensions of chips for OSB production: length - from 75 to 150 mm with a width of 15 mm and a thickness of 0.6 mm (respectively, small and large fractions are screened out and can be used for other purposes).

Also not mentioned are fan coolers, bringing the temperature of the plates to normal after hot pressing, and conveyor belts that move semi-finished products within the workshop. In addition, you will also need packaging equipment and forklifts (diesel or electric).

Prospects for the production of OSB

Of course, the best prospect in the production of OSB is the simple growth of the enterprise: after all, today there is simply no competition, at least in our country.

However, as in other woodworking industries, a large amount of “business” waste accumulates during the production of OSB: these are non-fractional chips, sawdust, and tree bark. It is fashionable to process such waste, for example, into pellets or combustible briquettes, which are used to heat the press, dryer, swimming pools, and also heating industrial premises in winter time.

Also, the specifics of OSB production equipment allows you to open a parallel production, for example, chipboard - this will practically not require investments. Among other things, the opening of a small carpentry workshop will allow taking orders for various light building structures - for example, booths for security guards, sheds, outdoor toilets and much more.

OSB production video

Preparation of raw materials (wood chips production)

Logs are usually delivered to the site. As soon as the raw materials have arrived at the plant site, they are immediately unloaded using forklifts, a specially designed hydraulic manipulator or a crane with a clamshell grip. Part of the wood is piled up at the raw material exchange, part is immediately put into production. Further, the required volume of raw materials for a given time is immersed in steaming pools, after which they are debarked. If the wood is recently felled and not frozen, then it is immediately allowed for debarking and further into the chipper. Currently, there are three types of chippers that are used to produce OSB chips. The already traditional chipper for short wood chocks. There are also disc chippers that shred whole logs. They use a different system for feeding and fixing wood during the cutting process. For processing logs without preliminary bucking, rotary (ring) chippers are also used. These machines differ from disk machines in the design of the cutting tool.

Raw shavings after the chipper are accumulated in special bins, from which they are fed in portions to the drum of the dryer. In the production of OSB, three-pass or single-pass drum dryers are most often used, as well as their combination - three-pass / single-pass. In some industries, you can see more modern three-section conveyor dryers. The concept of conveyor drying of OSB chips was borrowed from the food industry - potato chips production technology. Conveyor dryers have a number of advantages over traditional drum dryers. First, conveyor dryers allow longer chips to be dried without damaging them. Secondly, the entire stream of chips is dried more evenly, and the temperature at the outlet of the conveyor dryer is lower than that of the drum dryer.

This is a very important circumstance, because the lower the dryer outlet temperature, the higher the fire safety of the process and the lower the emission of pollutants (volatile organic compounds). After drying, the chips are sorted to separate too small and too large chips from the main stream. Suitable chips are sometimes additionally sorted, especially if the inner layer chips will be laid out on the forming conveyor randomly, without orientation. In this case, larger, well-shaped chips are sorted into the outer layer, where the chips are oriented. The rest of the chips are allowed on the inner layer of the OSB-plate. The sorted chips are accumulated in dry chip bins. Small and too large chips are transported to the dry fuel bunker of the boiler room.

The process of mixing chips with resin and paraffin is carefully controlled. To resinify the chips of the inner and outer layers, different mixers are used. They have the same design, but the composition of chemicals supplied inside, as a rule, is different. In general terms, the mixer is a cylindrical drum that rotates at a given speed. Inside the drum, paraffin, resin and other glue components are fed through separate pipelines. But, no matter what paraffin is used, raw or emulsified, it is injected before the resin. Most often used for inner and outer layers different types pitches. The resin for the outer layer may be supplied in liquid or powder form, while the resin for the inner layer may also be phenol-formaldehyde or isocyanate. The consumption of isocyanate resin for chips of the inner layer is always higher, because. it hardens faster and at a lower temperature than phenol-formaldehyde. Often manufacturers increase the number of mixers to have more flexibility in resin type selection and to make it easier to switch from one adhesive formula to another.

Carpet shaping

The orienting chip head of the outer layer is somewhat similar to farm harrows. It consists of a series of circular discs that guide the falling chips, aligning them parallel to the long side of the carpet.

The orienting chip head of the inner layer consists of star-shaped rollers with flat blades. Rotating, they align the chips parallel to the width of the carpet, perpendicular to the direction of the conveyor. The dimensions of the elements of the orienting heads and the distance between them are adjusted to the dimensions of the chips so that they fall through the rotating disks or rollers before they carry the chips out of the orienting head. Layers with oriented chips are laid out on the conveyor moving below sequentially, one after the other. The orientation of the chips in the layers alternates as follows: longitudinal, transverse, longitudinal (in 3-layer boards). Each layer is formed by a separate orienting head and laid out by a separate forming machine.

During the formation of the particle mat, the density of the embankment is continuously measured to ensure its uniformity. On modern molding lines, the carpet is laid out on steel flat or mesh pallets, which are then fed into a hot press. Palletless conveyors can also be used (in lines based on a continuous press).

Pressing

The carefully prepared chip mat is fed into a hot press. The press turns the loose chipboard into a slab and polymerizes the binder contained in it. The task of the press is to compact the chip mat and raise the temperature inside it to a predetermined value. The solidification temperature of the resin is in the range between 170-200°C. Pressure and temperature must be measured within 3-5 minutes. The following types of presses can be used: multi-story, single-story, continuous. For the production of OSB boards of small and medium capacities, single and multi-storey presses are in demand.

The continuous press is equally suitable for the production MDF boards, Chipboard and OSB. Its advantages: increase in productivity by 10-20%, reduction of thickness differences in finished products, improved quality, simplified maintenance, minimal installation costs. The steel belts of the continuous press are heated with thermal oil to a temperature of 220 °C. The estimated curing time is 9 seconds per millimeter of board thickness. Dust and exhaust steam after the press are removed by a fan in a wet way.

Multi-storey type presses have earned a good reputation for their high reliability. Its advantages: uniform heating of the entire heating plate, reliable hydraulic system, automatic control system, simultaneous mechanism, the possibility of producing door leafs.

The single-deck press is designed to increase the return on investment for low capacity lines. The features of this type of press are: quick change of production parameters, carrying out changes in the length and width of the plates, ensuring the exact width of the plates and a fast pressing cycle.