Plywood is also called a splint, or fine core board, plywood, plywood, is the wood segment cut into veneer or by wood square planing cut into thin wood, with adhesive glued into three layers or multiple odd layers of plate material, adjacent layer veneer fiber direction is perpendicular to each other.
Veneers of different species and thicknesses are allowed to be pressed together at the same time in the same sheet of plywood, but two layers of symmetrical veneers require the same species and thickness. So in the plywood, with the most central veneer as the center, the veneers on both sides are uniform in color and thickness.
The use of plywood, in most of the main industrial developed countries will be used in the construction industry, followed by shipbuilding, aviation, truck, military, furniture, packaging, and other related industrial sectors. China’s plywood products are mainly used in furniture, decoration, packaging, building templates, cars, ships, and production and maintenance.
Length and width specifications are generally: 1220×2440mm,
Thickness specifications are generally: 3, 5, 9, 12, 15, 18mm, etc.
In the finished plywood, the inner veneer except the surface board is referred to as the medium board, Can be divided into the short-medium plate, and long-medium plate.
Common plywood veneer wood species are poplar, eucalyptus, pine, miscellaneous wood, and so on.
Plywood boards can be classified into super, primary, secondary, and tertiary boards according to their appearance.
Special grade: the board surface specification is smooth, with no holes/cracks/skin/dead joints, big burr,
Level 1: The board surface is flat, without skin/bark holes, seams, and joints,
Level two: the board surface is basically regular, with a small number of leather, bark holes,
Level three: the length and width of the board are not complete, and leather, bark holes, and defects.
Plywood sheet board is used as the outermost layer of plywood veneer, divided into panels, and backboards.
Common wood species used as plywood sheet board: Oguman, mahogany, poplar, birch, red olive, mountain osmanthus, ice candy, pencil cypress, big white wood, Tang wood, paulownia, yellow-olive, clone wood, etc.
Common plywood surface board wood colors are the peach face, red face, yellow face, white face, etc.
The production process of plywood is generally as follows:
Spin cut: The first spin cut the raw wood into a thin veneer.
Gluing: Apply glue to a thin-cut veneer
Germ formation: The combination of thin wood skins coated with glue.
Cold pressing: Cold pressing of thin veneer pieces of wood together into boards.
Hot pressing: hot pressing of the board after cold pressing.
Sanding: After hot pressing cooling, saw the edge, and then sand the surface of the plate
Because the plywood is composed of coated veneer according to the direction of the wood grain crisscross into the slab, in heating or not heating pressed into the condition, can overcome the defects of wood to a greater extent, improve the utilization rate of wood, so as to save wood.
Plywood is made of multiple layers, so it is much cheaper than solid wood.
The difference of the physical and mechanical properties of plywood in vertical and horizontal directions is small, which can greatly improve and enhance the physical and mechanical properties of wood, good dimensional stability, anti – warping, and cracking.
Plywood can retain the natural texture and color of wood, flat shape, width, and thickness is relatively large, so the covering ability is strong, and convenient application construction.
The first thing to investigate is the material of plywood, the price of different tree species for materials is different, we can choose the right variety according to the decoration budget when decorating.
General poor quality plywood, its board surface damage phenomenon is more serious, so for those board surface damage, or is the phenomenon of the board scar, in the purchase process need to pay attention to the quality of the board.
In addition, some boards are two different grain veneer paste together, so when buying to see whether the plywood seam is tight, there is no uneven phenomenon.
Observe whether the surface of plywood cracks, wormholes, bubbling, stains, and other bad marks.
Plywood generally has positive and negative two large board surfaces, its selection, the grain of both sides of the plate requires a certain clarity at the same time, but also has a certain smooth, no rough and uneven phenomenon, it is best not to have nodes.
See if the color texture of the plywood is consistent.
Because some plywood is glued, it is necessary to observe whether its color is consistent, whether the texture is consistent, and whether the color of the wood and furniture paint is coordinated, the color of the plywood to be purchased should be coordinated with the overall effect of decoration.
Then check whether the plywood work is fine.
Plywood in the selection should choose those do not lose glue board to be applied, plywood if degumming, not only affect the construction, but also cause pollution, so in the selection of the hand gently beat the board, if a crisp sound, it shows that the board is better, if a thick sound, it shows that the board degumming phenomenon.