plywood knowledge and plywood selection

1, according to the material classification can be divided into: solid wood, wood-based board two categories. At present, in addition to the floor and the door will use solid wood, generally we use the board is artificially processed wood-based board. 2, according to the molding classification can be divided into: solid board, plywood, fiberboard, decorative panel, fire board and so on. 1, solid wood as the name suggests, solid wood is the use of complete wood made of wood. These plates are durable, natural texture, decoration is the best choice. However, due to the high cost of such plates and high construction process requirements, they are not used much in decoration. Solid wood is generally classified according to the material name of the plate, and there is no uniform standard specification. 2, plywood plywood, also known as plywood, commonly known as the fine core board. It is made of three or more layers of one-millimetre thick veneer or sheet adhesive hot pressed. It is the most commonly used material for hand-made furniture. Plywood is generally divided into 3 cm board, 5 cm board, 9 cm board, 12 cm board, 15 cm board and 18 cm board six specifications (1 cm is 1mm). 3, decorative panel Decorative panel, commonly known as the panel. Is the solid wood precision planing and cutting thickness of 0.2mm or so thin veneer, plywood as the base material, through the adhesive process made with a single decorative decorative plate. It is a special way for the splint to exist, with a thickness of 3 centimetres. Decorative panel is a kind of advanced decoration material which is different from mixing oil at present. 4, joinery board Joinery board, commonly known as large core board. The large core board is composed of two boards in the middle of the glue splicing wood. The price of large core plate is cheaper than that of fine core plate, and its vertical (differentiated by core material direction) flexural and compressive strength is poor, but the transverse flexural and compressive strength is higher. 5, particleboard particleboard is the use of wood scraps as the main raw material, and then infiltration of glue, additives by pressing the thin sheet. According to the pressing method, it can be divided into extruded particleboard and flat particleboard. The main advantage of this type of plate is that it is extremely cheap. The disadvantage is also obvious: the strength is very poor. Generally not suitable for the production of larger or more powerful furniture requirements. 6, density board Density board, also known as fiberboard. Is wood fiber or other plant fiber as raw materials, the application of urea formaldehyde resin or other applicable adhesive made of artificial board, according to its density is different, divided into high density board, medium density board, low density board. The density board is also easy to reprocess due to its soft impact resistance. In foreign countries, the density board is a good material for the production of furniture, but because the national standard on the height board is several times lower than the international standard, the quality of the density board in our country needs to be improved. 7, fire-proof board Fire-proof board is the use of siliceous material or calcium material as the main raw material, with a certain proportion of fiber materials, lightweight aggregate, adhesive and chemical additives mixed, made of autoclave technology decorative board. It is a new type of material that is being used more and more, and its use is not only because of fire protection factors. The construction of fireproof board has relatively high requirements for pasting glue, and the better quality fireproof board is also more expensive than the decorative panel. The thickness of the fire board is generally 0.8mm, 1mm and 1.2mm. 8, melamine board Melamine board, the full name is melamine impregnated film paper veneer wood-based board. It is a decorative board made of paper with different colors or textures soaked in melamine resin adhesive, and then dried to a certain degree of curing, and then paved on the surface of particleboard, medium density fiberboard or hard fiberboard, and made of hot pressing. Melamine board is a kind of wall decoration material. At present, some people use melamine board to fake laminate floor for floor decoration, which is not suitable. According to the requirements of the "formaldehyde release limit of wood-based panels and their products in Interior decoration materials" implemented from January 1 this year, the formaldehyde release amount of building materials directly used indoors must be less than or equal to 1.5 mg per liter, if the formaldehyde release amount is less than or equal to 5 mg per liter, it must be used indoors after finishing treatment. Formaldehyde emissions above 5 milligrams per liter are considered substandard. Bringing unqualified wood home is like adding a gas generator to a new home, and buying building materials must first look at environmental protection. 1, the woodworking board "large core board" : good moisture proof effect, can not be painted directly in the middle of the woodworking board is the core of natural wood adhesion, both sides are glued to a very thin veneer, as the name suggests, is one of the most important materials in the decoration. Can do furniture and packaging wooden doors and door covers, heaters, curtain boxes, etc., its waterproof and moisture-proof performance is better than particleboard and medium density board. In the selection of its internal wood, it should not be too broken, the gap between the wood is about 3mm of the joinery board is appropriate. Because the wood grain exposed on the surface is not beautiful, it is rarely painted directly, and it is usually pasted with veneer plywood. Furniture made with large core board and other wood to go through the two processes of adhesive board and painting, the cost is higher. The large core plate is divided into 3, 5, 9 cm plate according to the thickness, we can choose according to the pressure and strength, the thicker the price is higher. Many consumers choose large core board, one look at the weight, the second look at the price. In fact, the heavier the large core board, the worse its quality. Because the greater the weight, the more indicates that the board used miscellaneous wood. This kind of large core board made of miscellaneous wood cannot be nailed at all, so it cannot be used. In addition, the price of a very low large core board, its quality will certainly be poor. Either the gap is too large, or substandard wood is used. So when you choose, it is best to choose a large core board of about 100 yuan. This price of large core board, its quality is relatively stable. Market price for sale at 50? 55 yuan a large core board, can not be used. The selection of large core board is to look at the appearance: one side of the large core board must be a whole board, and the other side is only allowed to have a joint. In addition, the surface of the large core plate must be dry and clean. In addition, when you choose a large core board, be sure to saw a corner and check the quality inside. Inside the splicing of small wooden strips, the gap can not exceed 5 mm, can not be used with bark, holes and dead knots of wood. The large core board of better quality, among which the small wooden strips, are connected by a zigzag mortise. In use, the large core board can only be "opened" along the long side, and can not be sawed open horizontally. In addition, the large core board can not be used as a panel, and a layer of plywood should be pasted on the outside as a panel, otherwise there will be problems such as paint bubbles. 2 Integrated wood, not easy to deform This is a new kind of solid wood material, the use of high-quality imported large-diameter logs, deep processing and like fingers staggered splicing wood. Due to different processes, the environmental performance of this board is superior, it is 1/8 of the amount of formaldehyde allowed in the large core board, and the price is about 200 yuan per board, which is slightly more expensive than the high-end large core board. But on the other hand, this board made of solid wood such as American spruce can be directly colored and painted, which saves a process than the large core board, and the cost of construction may be equal in the end. 3, the density board than particleboard nail holding force difference particleboard is natural wood crushed into particles, pressed into a board, is the main material of the current cabinet. The medium density board is formed by pressing powdered wood chips, and the flatness is good, but the moisture resistance is poor. In contrast, the density board nail holding force is worse than particleboard, if the screw is loosened after tightening, because the density board strength is not high, it is difficult to fix, so it is rarely used for cabinet. 4, the decoration of three plywood save trouble and cheap multi-layer board, also called three plywood and plywood, the number of layers is different. According to the thickness of 3-9 cm, it can also be called 3-9 cm plate. Its advantages and disadvantages mainly look at the raw materials, Liuan core each 1.2m? The price of 4m plate is 10-20 yuan. But mahogany and poplar are cheaper. Now the main use of home decoration is three plywood, that is, in the factory has been very thin solid wood veneer affixed to the three plywood. Veneer plywood is easy to use, and the price is cheaper than buying decorative panels and letting the construction team stick them. 5, melamine double paste board, not afraid of fire and water This board is shiny on both sides, very hard, not afraid of water and fire, mainly used in furniture and cabinets. The price is more expensive, 1.2m?? The 4m size of the board ranges from 80 yuan to 140 yuan each. 6, the decorative panel, manufacturing the same effect as solid wood Decorative panel is the veneer of high-grade wood with obvious wood grain, very thin, the thinest is only 0.3mm, and the thick is only 2-3mm. Common wood bark color from light to deep, there are cherry wood, maple, white beech, beech, manchu, white oak, red oak, teak, rosewood, walnut, white shadow wood, red shadow wood and other dozens of varieties, the price is not cheap. Large area use, it is best to buy the veneer three plywood directly. If the veneer is used locally alone to achieve a unique effect, a higher process is required. When the moisture content of the wood is higher than the equilibrium moisture content of the environment (the average annual moisture content of the Beijing area is 11.4%), the wood will dry and contract, and on the contrary, it will absorb moisture and expand. The main reason for wood cracking and deformation is that the moisture content is too high or too low. Qualified wood needs to go through the factory's high-temperature cooking and drying process, and finally reach the local water content level. Therefore, the moisture content of wood is particularly important