A kind of plywood for weather resistance, water resistance, durability of plywood, from here have advantages of high temperature resistance, steam treatment;The two kind of plywood is waterproof plywood, which can be soaked in cold water and soaked in short time;The three kind of plywood is moisture resistant plywood. It can be dipped in cold water for a short time and is suitable for indoor use at normal temperature. Used for furniture and general building purposes;Four types of plywood is not waterproof plywood, used in indoor normal, general use plywood beech, basswood, ash, birch, elm, poplar etc..
Symmetry principle: single center plane plate on both sides of the water regardless of species veneer thickness, layer, manufacturing method, fiber direction and single board rate should correspond with each other, which is symmetrical on both sides of the center plane of the corresponding layer plywood the principle of equivalent stress in different directions. Therefore, when the change of veneer moisture content, its stable structure, no deformation, cracking and other defects; on the contrary, if the symmetry center plane of corresponding layer there are some differences, will make the center plane on both sides of single board stress is not equal, the deformation and cracking of plywood.Principle of odd number layer: because the structure of plywood is adjacent layer, the fiber direction of single board is perpendicular to each other, and must accord with symmetry principle, so its total number of layers must be odd number. Such as: three laminates, five laminates, seven laminates and so on. When the odd ply plywood is bent, the maximum horizontal shear stress acts on the central veneer to make it have greater strength. Even when the plywood is bent, the maximum horizontal shear stress acts on the adhesive layer, not on the veneer. It can destroy the adhesive layer and reduce the strength of plywood.
Decorative panel for decorative veneer plywood, it is natural wood or wood chipping technology into a certain thickness of the sheet, adhesion to the surface of plywood, a surface material for interior decoration or furniture manufacturing and formed by hot pressing. The common decorative panels are divided into natural wooden veneer panels and artificial veneer panels. The difference of appearance between artificial veneer and natural wood veneer is the basic texture for straight texture or pattern rules; the latter is natural wood texture pattern, natural pattern, variability is relatively large, irregular. The utility model has the advantages of not only the graceful pattern of the wood, but also the full utilization of the wood resources and the reduction of the cost.
Plywood is a piece of wood which is cut into large single plates in the direction of ring rings. After drying and gluing, the plywood is made of plywood and glued together according to the principle that the adjacent wood layers are mutually perpendicular to each other. Single plate number is odd, generally three to thirteen layers, there are three common plywood, plywood, plywood, plywood (nine and thirteen on the market known as the three board, five board, nine board, thirteen board). The outermost single panel is called the panel, the reverse is called the back plate and the inner plate is called the core plate.
