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Humidifiers and parquet

        
  1. What is hygroscopic
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  3. Classification of wood on the degree of moisture
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  5. Humidifiers and parquet .
Humidifiers and parquet

Wood is a natural material susceptible to fluctuations in temperature and humidity. Its main properties include hygroscopic, ie the ability to change the moisture content in accordance with the surrounding conditions. They say that wood " breathing ", that is, absorbing a pair of air (adsorption) or releases them (desorption) in response to changes in the room climate. Or absorption of vapor is carried by the cell walls. At constant environmental humidity level of wood will tend to a constant value, which is called the equilibrium (or sustainable) moisture.

On the ability to absorb moisture affects not only the indoor climate, but also wood. The most hygroscopic species are beech, pear, Kempas. They are the most rapidly respond to changes in the humidity level. In contrast, there are stable rock, such as oak, merbau, etc. They include a stalk of bamboo, very resistant to adverse climatic conditions. It can be laid even in the bathroom. Different types of wood have different levels of humidity. For example, birch, hornbeam, maple, ash has low humidity (15%) and when dry tend to cracking. Humidity oak and walnut is moderate (20%). They are relatively resistant to cracking and dry out less quickly. Alder is one of the most resistant to drying rocks. Its moisture content is 30%.

Humidity - one of the main characteristics of wood. Under wet wood understand the percentage ratio of the mass of water to the dry weight of the wood.

The absolute humidity is the ratio of the mass of the wood moisture present in a given volume of wood to the weight of bone dry wood. According to state standards, the absolute humidity of parquet should be 9% (+/- 3%).

The relative humidity of the wood - is the ratio of the mass of water contained in the wood, the weight of the wood wet.

There are two forms of water in the wood - bound and free. Of these, the sum total amount of moisture in the wood. Linked (or hygroscopic) moisture contained in the cell walls of the wood, and takes half a free cells and intercellular spaces. Free water is removed more easily than related, and to a lesser extent, affects the properties of wood.

According to the degree of humidity of wood distinguish the following types:

                                        
            
                    
  1. Wet wood. Its moisture content is more than 100%. This is possible only under the condition that the wood has long been in the water.
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  3. freshly cut. Its humidity is 50 to 100%.
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  5. The air-dry. This timber is usually stored for a long time in air. Its moisture content may be 15-20%, depending on the climatic conditions and the season.
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  7. room-dry wood. Its moisture content is typically 8-10%.
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  9. absolutely dry. Its moisture content is 0%.
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At the drying the water evaporates from the wood, which can result in significant deformation of the material. The process continues until the moisture loss until the moisture level in the timber reaches a certain limit which depends on temperature and humidity. A similar process occurs during sorption, i.e. the absorption of moisture. Reducing the volume of linear wood by removing from it the bound moisture is called shrinkage. Removal of free water does not cause shrinkage.

Shrinkage varies in different directions. On average, the total linear shrinkage in the tangential direction is 6-10%, and radially - 3.5%.

With the full shrinkage (that is, one in which all the bound moisture is removed) moisture content is reduced to limit water absorption, that is, to 0%.

In the non-uniform distribution of moisture in the wood drying it can form internal stresses, that is stresses occurring without the participation of external forces. Internal stresses can cause changes in the size and shape of parts for machining wood.

The properties of wood directly determine the properties of wood products. When excessive or insufficient moisture content of wood is usually absorbs moisture and gives correspondingly increasing or decreasing in volume. At high wood humidity can swell, and the shortage of moisture, it typically shrinks, so that all wood products, including flooring require careful maintenance. To prevent deformation of the floor covering in the room is necessary to maintain a constant temperature and humidity. This is beneficial not only to the quality and durability of flooring and wooden furniture, but also on human health. When a sudden change in temperature and humidity in the room in the wood internal stresses that result from cracks and deformations. The optimum temperature in a room with parquet floors and should be about 20 degrees Celsius, and the optimum humidity - 40-60%. To control the temperature in the room used hygrometers and relative humidity in the room is maintained with the help of a humidifier.

The properties of the wood also depends on the seasonal changes in the microclimate of the premises.

In the heating season, which lasts from October to April, the room temperature rises and the humidity drops. Moisture level drops below the floor level of 25%. These differences have a negative impact on the general condition of the wood. Wood planks vary in size, the crack, the seams between them may diverge and form a small gap. In the coating may develop cracks. To eliminate these effects can be by lowering the temperature and increasing the humidity in the room.

In the summer of flooring absorbs more moisture. Relative humidity can reach 60%. During this period, the process is reversed: the excessive moisture content strips swell find one another and their edges are raised, and the cover is deformed. In this case, to restore coverage, you must regularly ventilate the room, or use the air conditioner and turn on the heating in order to reduce the moisture content.

Warp staves when changing seasons can be very significant. If you change the relative humidity up to 30% in winter to 60% in the summer at a temperature of 20 ° C, the equilibrium moisture content can vary by 5%.

Control the humid-temperature conditions in the room is possible by means termogidrometra. This will help to take timely action and prevent deformation of the coating. The temperature in the room can be changed using the air conditioner. To increase the humidity can put open containers of water (perfect for this purpose are aquariums, fountains, etc.) or purchase special humidifiers with built-in analyzer climate.

Humidifiers without significant energy costs will create a favorable climate in the room, to ensure the proper level of humidity. There are various types of air humidifiers (steam, ultrasonic), depending on the method of evaporation of water.

For parquet floors and wooden furniture are ideal ultrasonic or traditional humidifiers . They protect the wood and furniture coatings from cracks and cracks of wood.

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