Drying chambers for wood. Making a dryer for lumber with your own hands. Drying lumber in a tubeless cassette dryer

High-quality lumber is the dream of many manufacturers who use wood as the main raw material for construction. But buying a drying chamber for lumber is an expensive procedure, and finding modern, high-quality drawings is almost impossible.

Manufacturers present figurative illustrations with general designations that do not correspond to complete documentation, which could be used to produce a high-quality drying installation for the production of lumber.

At the same time, there are drawings on the network for the following types of drying chambers:

Belt drying chambers
Aerodynamic dryers
Convection chambers with room diagram

What types of drying chambers for lumber are there and where can I find drawings?

This is exactly the question many manufacturers face. quality materials made of wood. And as practice shows, it is very difficult to find something useful. To obtain high-quality documentation, you almost always need to pay considerable amounts. Some manufacturers sell drawings according to which the products offered can be manufactured. There is also a service for device design, modernization and restoration of old wood drying chambers. The design of drying chambers consists of the following structural elements:

Gates/doors
Heating elements
Thermal unit
Vacuum unit
Automation
Installation solid fuel boiler working on wood, coal, etc.

If you have an old and ineffective drying chamber, or want to rebuild one minimal costs, at the same time with high quality drying of boards and even timber, then you can turn to the services of our company.

Our company is engaged in the re-equipment of cameras mainly vacuum type for high-quality drying of wood. It doesn’t matter at all whether it has a convective or air heating method. In any case, after our modernization, the equipment acquires a second life, providing the customer quality lumber as soon as possible.

Production and re-equipment of drying chambers

Designing homemade vacuum chambers is quite a labor-intensive task, requiring high competencies and experience and detailed diagrams; in the absence of such experience, the quality of chamber drying often does not reach even average levels. The number of defects becomes prohibitively large, and you may encounter an emergency at the enterprise. Due to the effects of vacuum, if the design is incorrect, the housing may simply “collapse”, which can cause collective injuries.

To summarize, the main risks when using a homemade camera are:

poor quality of lumber at the output
high power consumption
high number of defects
high cost of drying
long drying speed
fires and other emergencies at the enterprise

Our company’s services allow you to implement safe methods re-equipment using all necessary security systems and pressure level control sensors.

Wood dryer design - diagram

We not only help to equip, but also completely re-equip the camera on a turn-key basis, and the cost of the service will be less than the price new installation. We develop projects for drying production facilities with a capacity of up to 8,000 cubic meters. dry wood per month. We help make your business safer, more stable and more productive at a lower cost. But if you want to purchase a new drying chamber, we offer a complete set with documentation and operating instructions.

Drying chamber project

Our company develops individual projects dryers for any volume of output. Using different energy sources. Our drying chambers operate on firewood, slabs and other production waste. The enterprise is equipped with vacuum drying chambers created according to modern technology using contact heating. The chambers dry the lumber less than 24 hours before the molding moisture content. About 3 days before carpentry moisture. The timber is also dried over 3 days evenly over the entire depth of the lumber. The timber does not warp or tear during further use in the structure of the house. Shrinkage is only about 1%. The cameras can be connected to a waste boiler or to solar panels. Recycled heat from equipment is used for heating production premises. This allows you to save huge amounts on electricity throughout the year.

Vacuum chambers for drying wood

In vacuum chambers, timber is dried under conditions high pressure 700 mmHg Art., but at a low temperature of 45 C. A vacuum is specially created in these devices, which entails high energy costs.

Vacuum drying is an extremely expensive method of drying timber for a number of reasons:

expensive vacuum chambers
huge amount of electrical power for proper operation

In such devices, timber is dried for one to two days. For example, to dry 40 m 3 of boards it will take approximately 8-16 days. And if the timber is vacuum dried, it will take even more time.

Due to the high cost of the process, vacuum drying of wood is carried out mainly for expensive types of timber, such as oak, ash, beech, and cedar. In such cases, it is necessary to dry a large number of lumber. For mass production of lumber, convective drying chambers are used because they are more accessible and have a low cost.

Some examples of vacuum drying:

oak boards 52 mm thick with a humidity level of 50% will dry to a humidity level of 4-5% in approximately 28 - 35 days
oak boards 52 mm thick with a humidity level of 30% will dry to a humidity level of 4-5% in 16 - 18 days
oak boards 25 mm thick with a humidity level of 50% will dry to a humidity level of 4-5% in approximately 15 days
oak boards 25 mm thick with a humidity level of 30% will dry to a humidity level of 4-5% in 9 days
pine boards 55 mm thick with a humidity level of 50% will dry to a humidity level of 5 -6% in approximately 8 days
pine boards 55 mm thick with a humidity level of 30% will dry to a humidity level of 5-6% in 6 days
building timber 100 x 100 mm and 150 x 200 mm with a humidity level of 65% will dry to a humidity level of 6% within 8 - 12 days. A beam of 200 x 300 mm will need 22 days to achieve the same parameters.

Under vacuum conditions, wood drys more gently. However, even with this drying method, cracking is possible. Wood is a living raw material. Wood is inherent different types stress. These stresses depend on the area in which the tree grew, on the cutting method, and on age. When drying wood, even in such chambers, not all stresses are relieved evenly.

How does vacuum drying of wood occur?

Injecting a vacuum inside the chamber where timber is dried significantly changes the physical nature of heat and mass transfer processes in wood. Drying is carried out by the action of a constant vacuum of 0.95 MPa and steam generated from the moisture of the timber. Since there is a natural movement of the drying agent at a speed of up to 0.3 m/sec, there is no need to use fans, lumber humidification systems, or install a dry/wet thermometer. Drying is controlled by lumber moisture sensors. For example, during the drying of oak lumber from an initial moisture level of 65% to a residual moisture level of 6%, about 450 liters of moisture are released. If you load a maximum of 12 m 3 of oak with a thickness of 55 mm into the chamber, the total amount of moisture will reach 5,400 liters.

Today, all companies producing vacuum drying chambers have certificates of compliance with European standards. In such devices you can dry simultaneously various varieties wood.

Drying quality:

the residual level of importance is from 6 to 0.5%
the difference in humidity level across the stack does not exceed 1%
The difference in humidity level along the thickness and length of the board does not exceed 0.9%.

DIY vacuum drying of wood

The drying process is very beneficial when done with your own hands. However, purchasing a factory-made vacuum chamber is quite expensive; in this section we will tell you how to make one yourself. Drying at home can be done in a special chamber, which requires a spacious room, a heat source, and a fan to distribute the heat inside the chamber.

The best option for creating a chamber is an iron conveyor. You don't have to buy a new one, you can find used ones. In addition, you can weld the chamber yourself from old iron.

In order to retain heat inside the chamber, the walls need to be insulated with foam plastic and lined with clapboard. In addition to polystyrene foam it will be suitable mineral wool and any other insulation material. In order for heat to be reflected from the surface, it is necessary to lay a special material. You can use foil or penofol. By the way, the heat-reflecting and preserving qualities of penofol are much higher.

After this you can start assembling heating device. All heating system must be installed separately from other heating circuits; it must be constantly functioning. Will do heating radiator, which heats the water to 65-90 degrees. To distribute heat evenly in the chamber, it is worth purchasing a fan. Without it, drying will not occur evenly, and the final product will have low quality. Don't forget the rules fire safety during the creation of a vacuum dryer.

Another important point can be called the creation of a system for loading lumber into a chamber. For this purpose, you can use trolleys that move on rails or a forklift. Raw materials are placed on shelves or directly on the floor to dry. To monitor the drying process, you need to install special sensors - thermocouples and pressure sensors. If you approach this event wisely, you will end up with a chamber for drying high-quality lumber.

After loading the raw material into the chamber, the door closes tightly and the drying process begins. Under such conditions, bound and free liquid will move smoothly from the center to the periphery, which guarantees high-quality and uniform drying of the material. The dry top cells of the lumber absorb liquid from the cells located closer to the core. First, thin places dry out, then moisture from thick layers moves into already dry ones, making them wet.

To prevent displacement, a special mixture is applied to the lumber, which is made from chalk and drying oil. Most often, this mixture is applied to the end parts of the workpieces.

For the quality of any type of structure, it is important that the materials used are also of high quality and durable. And when it comes to wood, it must be dry, durable and resistant to rot.

To give the tree such properties, it needs to be dried. But purchasing equipment for heat treatment of wood is very expensive, so many craftsmen are trying to build their own.

A DIY lumber drying kiln may be good value for money, but it is far from perfect. Indicators such as 6% humidity in a couple of days with less than 1% defects in it are clearly unattainable, since assembly is usually carried out from improvised means without the use of sensors and various smart systems control of various wood parameters, and most importantly, practically without experience in creating drying chambers.

Features of self-made drying chambers

A homemade drying chamber is a room in which a heater is installed. Now it’s worth thinking about, if for drying 1 cubic meter. m will require at least 16 kW of energy, whichever is needed within 3-4 weeks (this is usually the standard drying time in such chambers. Costs can be many times higher than the prices of the materials themselves. Plus, if not observed temperature conditions, poor-quality heating along the length and lack of control over the percentage of humidity, the boards are deformed in almost 100% of cases, which makes them very difficult to work with.

The design of such cameras must be realized using detailed calculations. If technology is not followed, various accidents occur. For example, the chamber body under the influence of vacuum can shrink like an aluminum can and other moments are often life-threatening for workers.

It is also necessary to take into account the source of energy. Running on electricity is expensive. It is more efficient to operate a drying chamber using wood using a solid fuel boiler.

The undeniable advantages include the possibility of significant cost savings. Since a high-quality camera is often expensive to purchase. But the expected savings may actually turn into significant losses.

pros

There are many reasons for this.

For example:

task self-made drying chamber is very complex. To solve it, you will need to purchase raw materials, necessary equipment. And, most importantly, the presence of specialists on staff who can do everything necessary calculations, and build this object;
The slightest inaccuracies in calculations and construction technology can lead to a significant increase in the volume of defects. And these are direct losses, violation of delivery deadlines, loss of business reputation and image of the enterprise. Moreover, these errors can lead to destruction of the chamber itself (for example, the vacuum chamber will “collapse” like a tin can);
significantly higher energy consumption.

Example.

Drying a cubic meter of lumber in a homemade chamber requires an average of at least 16 kW. Calculate monthly expenses (even with an 8-hour working day and a 5-day working week).

The parameters of finished lumber, which are provided by vacuum chambers manufactured by a specialized enterprise (for example, a moisture level of 6%, achieved in two days of work, or a defect rate not exceeding 1%), are practically unattainable in home-made devices.

Possible design options

If an objective analysis has shown that the company is capable of solving all the upcoming difficulties associated with manufacturing, commissioning and subsequent operation, we can begin a detailed study of this issue.

To do this, you need to answer several questions:

what drying mode will be implemented in it (the required temperature in the chamber depends on this): low temperature or high temperature;
its future structure (prefabricated metal, or built from existing building materials (concrete, brick, blocks, etc.);
installation location (separate building, workshop area). Since from such a decision depends on the calculation of subsequent work (foundation, laying engineering communications, delivery of raw materials, etc.);
loading option (forklift, rail cart);
heat supply option (hot air, radiant energy, superheated steam, electric current, other options);
decide on the required equipment for the future furnace (main and auxiliary).

The first group necessarily includes a humidification and ventilation system (supply and exhaust), heat supply. Secondly, psychrometric and insulated door blocks, electric motors for fan drives, stacking trolleys, etc.

option for organizing process control (manual mode, semi-automatic, auto mode). Ideally, remote control of processes can be provided.

All of the above issues are resolved in the context of the selected type of drying chamber. Today there are chamber and tunnel options (they implement convective heat exchange).

The first ones are shorter than the second ones and, most often, for loading raw materials and unloading finished products one door is used. As a rule, this option is chosen.

Tunnel systems provide for the movement of materials during operation along the entire length of the chamber. Loading, on the one hand. Unloading from the opposite side. These cameras are used in large enterprises.

There are condensation type drying chambers. They have significant efficiency, but the drying process is very long in time (the equipment is not able to work in conditions high temperatures). This leads to significant heat loss and increases energy consumption.

There are many more criteria that must be taken into account when making calculations:

method of circulation of the agent used for drying;
its characteristics;
type of fencing being performed;
operating principle;
circulation method.

Each of these issues directly affects the drying speed, the possible volumes of lumber loaded at a time, and the characteristics of the finished product.

In addition, it is necessary to take into account the type of wood, its initial moisture content, and the geometric dimensions of the lumber.

A careful analysis and detailed calculation will, with a high degree of probability, prove economic feasibility purchase and installation of a ready-made drying chamber. Although, in some cases, making it yourself can also be cost-effective.

How can we help?

The Falcon company has been producing vacuum chambers for drying wood for almost two decades. Cooperation with us is beneficial both for those who are going to make their own drying chamber, and for those who want to purchase a finished product in order to have a guaranteed quality products in commercial volumes.

We are ready to offer our partners from the first group the equipment and units that are necessary for the functioning of the cameras in our range. An example is heating panels in which the coolant is water.

They can be installed in structures of any volume, are designed for operation in a vacuum environment, and are capable of operating at high temperatures.

Panels can be selected according to a number of characteristics:

according to the volume of the chamber for which they are purchased (we offer 4 design options - for volumes up to 3 cubic meters, up to 8, up to 15, up to 21);
they can be equipped with automatic equipment in a standard, maximum or optimal version for the customer;
by size: 2000*3000 or 1500*3000.

In addition, we offer complete heating units, pyrolysis boilers, liquid NPs, vacuum units and automation completely ready for installation.

We manufacture automation for chambers of each type: Convective, aerodynamic, vacuum, etc.

Significant advantages of purchasing ready-made solution are:

significant time savings (it takes at least 14 months to independently develop a project and complete it);
savings on unplanned expenses. Practice shows that bringing the performance characteristics of a homemade camera to the required parameters requires an amount comparable to (or exceeding) the price of a finished camera;
guaranteed release of only high-quality products;
The company begins to receive net profit immediately after completion of the commissioning project. No time is required to fine-tune the equipment and characteristics of the finished product (downtime).

If you need to design a vacuum dryer, it is better to seek the help of professionals. We are engaged in production:

mobile,
stationary,
high efficiency,
low power consumption.

It is possible to design not only drying, but we can also supply new equipment at an affordable cost. Powered by both electricity and industrial waste: slabs, firewood, etc.

For those who know how to count money and save money own time and pays primary attention to quality, a wide range of vacuum chambers of our production is available, the main characteristics of which can be found on the website, in the company catalog or by personally contacting the nearest office.

We also sell more budget options from heating plates. You can find out more from the manager by phone or email on the main page.

Contents Vacuum drying as an alternative to a DIY microwave chamber Today there are many known methods for drying lumber, each with advantages and disadvantages. As an example, do-it-yourself microwave drying of wood. The technology is no longer new and quite productive. Microwave chambers are used for drying hardwood, large-section lumber, veneer, timber, and logs. Basically, after drying the material […]

There is not a single woodworking enterprise that can do without the wood drying procedure. To prevent the occurrence of various defects, it is customary to use special technology drying wood in a drying chamber. If you want to produce wood products yourself, you will also need a drying chamber for drying wood. Today we will talk about how to do it correctly.

The need to dry wood

How to dry a board efficiently and quickly? This question has interested every carpenter since ancient times. People have long been engaged in storing wood for many years in order to have time to dry it evenly. The grandfather prepared wood for his grandson, using the very material that his grandfather left him.

The importance of properly dried wood is colossal! For example, if wooden furniture, which is in the room, is made of too wet wood that has just been cut down, then it will dry out over time, because wood can dry out and decrease in size, which means it will deteriorate!

If the door to the house is made of excessively dry wood, it will swell over time and will not be able to close! If the door panel is assembled from blanks that are unevenly dried in volume, then it may burst or warp! Therefore, it is recommended to dry all wood blanks. In addition, drying protects the material from damage by wood-destroying fungi, prevents the size and shape of wood, and improves the physical and mechanical properties of wood.

Drying wood is a lengthy, complex and expensive procedure. Tree by traditional technologies heated with superheated steam or hot air. Dried wood can be transported and stored longer. In addition, it does not deform during operation. The boards are dried in steam chambers, where the possibility of internal damage is excluded.

Wood moisture concept

For full perception The essence of the drying process is worth diving into the theory a little. The procedure for removing moisture from wood is not entirely simple, because there are two types of moisture in the material itself. Wood consists of plant cells elongated shape. Moisture can be found in the cell walls and in their cavities, filling the microcapillary system. The moisture that is present in the spaces between cells and in their cavities is called free intercellular, and moisture in the cell walls is called bound intracellular.

The content of bound moisture in wood is limited. The state when the cell walls are characterized by maximum humidity when in contact with liquid moisture is called their saturation limit. It is generally accepted that the moisture content of the saturation limit does not depend on the rock and is on average 30%. If the wood's humidity is above 30%, then it contains free intercellular moisture. The wood of a freshly cut or growing tree has a moisture content above the saturation limit, that is, it is raw.

Depending on the purpose of wood blanks, wood is usually dried in different ways. The wood is dried to a moisture content of 6 - 8%, when the material is needed for mechanical processing and assembly of products for high-precision critical connections that affect performance (the production of skis, parquet or musical instruments).

Transport humidity is 18 - 22%. It is with this water content that lumber is suitable for transportation over long distances in warm seasons. Wood dried to such a moisture content is used mainly in standard house construction, in the production of ordinary containers and when there is no need for interchangeability during assembly.

Carpentry dampness is divided into several subspecies. Molded products ( terrace board, sheathing, floorboard, casing) must have a humidity of 15 ± 2%. Wood products (windows, doors, stairs and interior elements) made from solid or laminated wood can withstand humidity fluctuations from 8 to 15%.

Furniture humidity, depending on the level of the product and the use of solid or laminated wood, is 8 ± 2%, because it is at this humidity that the wood exhibits the most optimal characteristics for processing, gluing and subsequent use. But it is usually customary to reduce the humidity to 7-10%, performing partial sterilization of the wood and taking into account the uniformity of humidity throughout the tree, maintaining the mechanical properties of the material, and the absence of surface and internal cracks.

Wood drying modes

Depending on the requirements for the quality of wood, lumber can be dried different modes, which differ in temperature level. In a mini drying chamber for wood, during the drying process, the air temperature gradually increases in stages and the relative humidity of the agent decreases. Drying modes are selected taking into account the thickness of the lumber, the type of wood, the final moisture content, the quality category of the wood being dried and the design of the chamber.

There are low- and high-temperature process modes. The first modes involve the use humid air as drying agent, the temperature of which in the initial stage is less than 100 degrees. There are three categories of these modes:

The soft mode is capable of ensuring defect-free drying of the material while maintaining the natural physical and mechanical properties of the wood, including color and strength, which is important for drying wood to the transport moisture content of export lumber.
The normal mode guarantees defect-free drying of wood with almost complete preservation of the strength of the material with minor color changes, which is suitable for drying lumber to its final moisture content.
The forced mode maintains strength for static bending, compression and tension, but there may be a slight decrease in splitting or spalling strength with darkening of the wood, which is intended for drying wood to operational humidity.

For low-temperature modes, a three-stage change in the parameters of the drying agent is assumed, and from each stage to the next one the transition can be made only after the material reaches a certain level of humidity, which is provided for by the mode.

High-temperature modes provide for a two-stage change in the parameters of the drying agent, and you can move from the first stage to the second after the wood reaches a transitional moisture content of 20%. The high temperature regime is determined depending on the thickness and type of lumber. High temperature conditions can be used to dry wood, which is not used for manufacturing. load-bearing elements buildings and structures in which wood darkening and strength reduction are allowed.

Drying chamber concept

Chamber drying is the main method of drying wood. Drying chambers are required to dry softwood and hardwood to different quality categories. One of the most popular and economical methods of artificial dehydration of lumber is drying, when bound and free moisture is removed from the tree by applying heat to the wet wood with hot air and carrying away the evaporated excess moisture humidified and partially cooled air.

The drying chamber is completely ready installation, which is equipped with all the equipment necessary for drying wood. According to their design, wood drying chambers are divided into prefabricated metal and made of building materials. The latter are constructed directly in workshops or as separate buildings from materials that are widely used in industry. The chamber can be made entirely of monolithic reinforced concrete. Its walls can be made of solid red brick, and the ceiling can be made of monolithic reinforced concrete.

If several dryers are used, they are often combined into a single block, constructing a common control corridor where the heat supply distribution and automatic control system for all chambers are located. Depending on the volume of wood loaded into the chamber, there may be horizontal or vertical transverse air circulation.

Loading of lumber into the chamber can be carried out in the following ways: on trolleys in the form of stacks along a rail track, like packages with a forklift. Heat transfer to wood can be carried out: by air, combustion products or superheated steam; radiant heat that comes from special emitters; solid body, if you organize contact with a heated surface; current that passes through wet wood; high-frequency electromagnetic field that penetrates wet wood.

Equipment for a wood drying chamber is divided into basic and additional. The main ones include the fan system, heating system, supply and exhaust ventilation and humidification, additional components include an insulated door and psychrometric unit, stacking trolleys, and a fan drive electric motor.

The process of controlling wood drying in a chamber can be automated. Automation is capable of maintaining the humidity and temperature of the environment in the dryer at a given level. The temperature is regulated by supplying coolant to the heaters or by switching on and off electric heater, and humidity - through the use of supply and exhaust ventilation and a humidification system.

The wood drying control system may have the ability to remote control humidity and temperature in the chamber. When drying lumber in a drying chamber, it becomes necessary to control the moisture content of the wood, for which a remote moisture meter is used, which allows you to check the moisture content of the wood at several points without entering the chamber. In the absence of external sources of heat supply, autonomous heating modules can be used for the dryer and gas, coal, wood waste, electricity and diesel fuel.

Types of drying chambers

IN real life It is customary to use the following types of drying chambers. The necessary energy in convective drying chambers is transported into the material using the air cycle, and heat transfer to the wood occurs through convection. There are two types of convection chambers - tunnel and chamber.

Tunnel convection dryers are deep chambers where stacks of stacks are pushed from the wet end to the drier end. These chambers must be filled at one end and emptied at the other. Pushing the stacks (the process of filling the chambers and emptying them) is done one stack at a time with an interval of 4 - 12 hours. These chambers are designed for large sawmills and allow exclusively transport drying of wood.

Chamber convection drying chambers are shorter than tunnel and vacuum drying chambers for wood; during operation, the same parameters are maintained throughout the chamber. When the blowing depth is more than 2 meters, the technique of reversing the direction of ventilation is used to equalize the drying conditions for the wood. The emptying and filling of the chamber occurs on one side if it has one door. Other loading systems are also known that are similar to the procedure for loading tunnel chambers. Any lumber can be dried to any final moisture content, which is why 90% of wood in Europe and Russia is dried in chamber dryers.

The condensation drying chamber differs from the previous ones in that the humidity that arises in the air condenses on special coolers and water comes out of the drying process. The efficiency of such a process is large, but the cycle is long, because the devices do not operate at high temperatures, and the total heat losses are also significant. The condensation chamber is primarily suitable for drying small volumes of wood, or for drying dense wood species - oak, beech or ash. The big advantage of such chambers is that a boiler room is not needed, the price of a wood drying chamber and the cost of drying are lower.

Drying kilns are also classified according to the method of circulation and the nature of the drying agent used, the type of enclosure and the principle of operation. Batch drying chambers are characterized by the fact that they can be fully loaded to simultaneously dry all the material, and the wood drying mode changes over time, depending this moment remaining the same for the entire camera.

According to the method of circulation, there are chambers with incentive and natural circulation. Dryers with natural circulation are outdated, low-performance, the drying mode in them is almost uncontrollable, and the uniformity of wood drying is unsatisfactory. For modern construction such devices are not recommended, and existing ones must be modernized. Depending on the nature of the drying agent, the chambers are divided into gas, air and high-temperature chambers that operate in a superheated steam environment.

Wood drying procedure

Before drying according to the selected mode, the wood is heated with steam, which is supplied through humidifying pipes, with fans running, heating devices turned on and exhaust ducts closed. First you need to calculate the drying chamber for wood. The temperature of the agent at the beginning of heating the wood should be 5 degrees higher than the first stage of the regime, but not more than 100 degrees Celsius. The level of saturation of the environment should be 0.98 - 1 for material with an initial humidity of more than 25%, and 0.9 - 0.92 for wood with a humidity of less than 25%.

The duration of the initial heating depends on the type of wood and for coniferous species (pine, spruce, fir and cedar) is 1 - 1.5 hours for each centimeter of thickness. The duration of heating of soft deciduous trees (aspen, birch, linden, poplar and alder) increases by 25%, and for hard deciduous species (maple, oak, ash, hornbeam, beech) - by 50% compared to the duration of heating of coniferous species.

After preheating, it is customary to bring the parameters of the drying agent to the first stage of the mode. Then you can begin drying the lumber, subject to the established regime. Humidity and temperature are regulated by valves on the steam lines and gates of the sugar-exhaust channels.

During the operation of an infrared drying chamber for wood, residual stresses arise in the wood, which can be eliminated by intermediate and final moisture-heat treatment in an environment of increased temperature and humidity. It is customary to subject lumber to processing, which is dried to operational humidity and subject to machining further.

Intermediate moisture-heat treatment is carried out during the transition from the second stage to the third or from the first to the second at high temperature conditions. Subjected to moisture and heat treatment conifers from 60 millimeters thick and deciduous from 30 millimeters thick. The temperature of the environment during the heat and moisture treatment process should be 8 degrees higher than the temperature of the second stage, but not higher than 100 degrees, with a saturation level of 0.95 - 0.97.

When the wood reaches its final average moisture content, final moisture-heat treatment can be carried out. In this process, the temperature of the medium is maintained 8 degrees above the last stage, but not higher than 100 degrees. At the end of the final moisture-heat treatment, the wood that has undergone drying must be kept in the chambers for 2 - 3 hours at the parameters provided for by the last stage of the regime. Then the drying chamber is stopped.

Making a drying chamber

If you decide to make wood products yourself, then you simply need a wood drying chamber. However, when constructing a dryer, comply with all required standards. You will need a chamber, a fan, insulation and a heating device.

Build a drying room or select a separate room, one wall and ceiling of which will be made of concrete, and the other walls will be made of wood, which need to be insulated. To do this, it is customary to create several layers: the first of them is polystyrene foam, the second is wooden boards, which are usually wrapped in foil in advance.

After this, you should install a heating element, which can be made in the form of batteries. Water must be supplied to the batteries from the stove, in which it will be heated to 60-95 degrees Celsius. It is advisable to continuously circulate water using water pumps in the heating element. Also, a fan should be placed in a homemade wood drying chamber, which helps distribute warm air throughout the room.

Consider how the wood will be loaded into the drying chamber. One loading option could be a rail cart. To regulate the humidity and temperature in the drying chamber, you need to use work area corresponding thermometers - wet and dry. Provide shelves inside the dryer to increase work space.

During the drying process of lumber, sudden changes in temperature in the working room are not allowed, otherwise this will cause the wood to warp or cracks to appear in it. When constructing a drying chamber, it is extremely important to observe fire safety requirements. Therefore, in the immediate vicinity of the dryer in mandatory install fire extinguishers.

And finally, remember that instead of heating element At home, you can use a two-burner electric stove. You can insulate the walls of the drying chamber yourself using wood shavings. Instead of foil in the chamber, you can use penofol, which can provide good reflection of heat from the surface. In such a dryer, the wood is pre-dried 1-2 weeks in advance.

High-quality dried lumber has always been the key to quality, durability and reliability of any structure in which wood occupies a significant share. But it is difficult to obtain it under natural conditions without it spoiling. Drying time under normal atmospheric conditions can range from 6 to 12 months, depending on temperature and humidity environment. During natural heat treatment, the material is subject to unwanted deformation, warping and cracking.

To improve the quality of drying lumber, many equipment options have been invented; people often try to make a vacuum drying chamber for wood with their own hands - because this technology is considered one of the most effective. But the problem is that it is quite difficult to make such a unit yourself. Still, there are craftsmen who make them from old tank bodies or thickened sheet steel. These are mainly mini cameras with a loading volume of 5-10 cubic meters.

What is vacuum drying of wood with your own hands?

Vacuum drying of wood with your own hands is quite possible if you have a shell from a rocket, tank, or any other similar type of product from which you can make a shell for the equipment.

Main design elements:

frame
Vacuum pump
heating elements (heaters, plates, steam generator, microwave emitters, etc.)
trolley for loading lumber
automation

You will need a pump to pump out air and create a vacuum. You can heat lumber using any in a known way, which can be a contact method, air-gas and water vapor.

A do-it-yourself vacuum chamber is quite technically complicated, because it will be quite difficult to find many parts for its manufacture. And ordering them specifically is tantamount to ordering the camera itself. Therefore, before you start constructing vacuum drying chambers for wood with your own hands, you should consider whether it is advisable or whether it would be better to order it from a specialized company.

Do-it-yourself thermal chamber for wood - production of thermal wood

Thermal vacuum chamber technology has been around since the last century. The thermal dryer has much in common with a vacuum chamber for drying lumber.

To make a vacuum chamber for thermowood, you need to take into account the technical features:

Wood processing occurs at high temperatures
The chamber body must withstand high pressure

These 2 points are important to consider for the safety of personnel.

An important task is the choice of agent: oil or steam. Also technical modes. If the conditions are incorrect, thermal drying takes place only on the surface of the wood, and the lumber may not acquire the desired properties:

full color change
fire resistance
increased resistance to rotting

Do homemade camera for thermowood, as well as thermowood itself, at home is a difficult task. It is unlikely that you will be able to find competent specialists ready to share their experience on forums, videos, or somewhere on the Internet. If you have any questions, you can contact the manufacturers.

Vacuum dryers for wood: do it yourself or from professionals?

Our company has been producing high-quality and highly efficient vacuum-type drying chambers for several years, so we are ready to offer a truly reliable and practical option.

But if you need a vacuum dryer for small-sized wood for heat treatment small parts and you want to make it yourself, then you need a drawing. Drawings on this topic are quite a rare occurrence; of those that are encountered, it is unlikely that a camera capable of working in production conditions will be produced.

If you are still going to purchase ready-made equipment, then the most effective option are chambers with contact technology for heating lumber along the entire length, the percentage of defects is less than 1, and the drying time is up to 6-8% humidity pine boards 30mm thick will only take about 60 hours.