Wood is a natural material. As a decorative material for architecture and indoor furniture, wood has many advantages, such as light wood material and high strength; It is easy to process, the energy required for processing is low, and it is not easy to pollute the environment; Good insulation to heat and electricity; Good acoustic properties; Wood materials have strong cushioning effect on vibration; Wood has an omen before destruction; Wood resource materials have natural and beautiful patterns, luster and colors, and have special decorative effects. As an indoor material, wood has the function of adjusting the relative humidity of the room. However, as a natural organism, wood also has some problem during in wood processing and utilization. Among of them,warping is one of the most thorny problems encountered.
Let’s talk about how do you dry wood without warping? Before talk it we must know what causes wood warping? Knowing the cause of warped wood is the first step to know how to avoid this problem.
The cause of wood warping deformation and cracking is that wood has the characteristics of wet expansion and dry shrinkage. The rule is: when the moisture content of wood is below the fiber saturation point, the volume of wood expands with the increase of moisture content; With the decrease of moisture content and wood volume shrinkage, the longitudinal and transverse length dimensions are reduced, and the transverse shrinkage can be divided into radial and chord directions. Especially, there is a great difference in the proportion of longitudinal and transverse shrinkage of wood. Generally, the longitudinal dry shrinkage is about 0.1%, the transverse dry shrinkage is large, the chord dry shrinkage is up to 12%, and the radial dry shrinkage is about 3% ~ 6%. Therefore, the difference between longitudinal and transverse drying shrinkage of wood results in tensile stress along the tangent direction of growth rings. When the tensile stress is greater than the cohesion between wood cells, the wood will produce warping deformation
So, what should we do to prevent the wood crapping?
1.Store Wood Properly
When stacking wood, the bottom pad shall be flat, otherwise the stacked wood will warp and deform under its own heavy pressure. At the same time, there shall be wooden strips hanging up and down when stacking wood. Otherwise, the wood forest will not be ventilated and can not be dried in time, which will produce mildew and decay. The wooden strips used for space separation shall be aligned up and down. If the wooden strips are misplaced, the stacked wood will have multiple bends, which will seriously affect the utilization rate of wood.
2. Control The Internal Moisture Content Of Wood
There are two kinds of water in wood: free water and adsorbed water. Free water exists in the large capillary system composed of cell cavities in wood texture. The increase or decrease of free water will only affect the weight of wood, but will not affect the properties of wood itself; Adsorbed water exists in the micro capillary system composed of cell wall. The change of adsorbed water can not only affect the shrinkage and expansion of wood, but also affect the physical properties of wood. Therefore, the general wood drying is mainly to reduce the attached water, rather than reduce the composition of free water. All wood shall be treated with moisture-proof treatment to prevent wood deformation and cracking.
3. Hydraulic Pressure System During Drying Process
The high frequency vacuum wood dryer kiln produced from my company. It is equipped hydraulic pressure system on the top. It can supply 6-8 tons pressure on the wood stacking. It’s a good way to avoid wood crapping problem, kiln dry wood without warping. Welcome contact Mr.Carlos to talk about more details about high frequency vacuum wood dryer kiln
