There are hundreds of wood rot fungi in the world that erode the various woods that are in use, causing the decay of the wood. The decay of wood often shows the use value of wood, which is cracked, fiber-strong, mesh-like, etc.
Figure: Wood decay fungus
More than 200 kinds of soft rot fungi will cause soft use of ordinary wood that has been immersed in water for a long time and in contact with the soil for a long time, resulting in loss of use value. The sugar in the wood fiber can attract bacteria to erode the wood and rot. At the same time, the organic matter such as hemicellulose and lignin contained in the wood will provide a good living environment for the insects to be eroded.
In addition, physical and chemical factors in the outdoor environment directly or indirectly affect the untreated ordinary wood, such as weathering, deformation, discoloration and the like.
A serious flaw in wood is decay. The wood is under corrosive conditions and can be destroyed in 3 to 5 years. If it is handled well, it can not be decayed for a long time. For example, the wooden structure of the millennium or more left over from ancient China is proof.
The cause of wood decay is the damage of wood rot fungi, a minimal plant.
Wood rot fungi breeding conditions:
2, water, wood rot fungi secreted enzymes in water as a medium, the wood itself is broken down into sugar for nutrition, wood moisture content is 30% ~ 50% when the most decaying;
3, the temperature is 10~30. For example, the pile is completely immersed in water, and the water content exceeds 100%, so it is extremely rot, which denatures the wood and loses its physical properties.
The most important method of preserving wood is to reduce the water content. Under the general moisture content of 18%, the wood rot fungus cannot be propagated. At the same time, the wood should be ventilated to avoid moisture. If the ventilation is not good, the same humidity of the air is maintained at 80% to 100%, and the wood rot fungus can grow.
For direct damp wood products to be coated or soaked with preservatives, the preservatives are toxic, so that wood rot fungi can not breed and survive. The most commonly used preservative is coal tar.
Wire Mesh,Brass Wire Mesh,Copper Wire Mesh
Metal Wire,Fence,Wire Mesh Co., Ltd. , http://www.nsmeshmetals.com