Plywood product knowledge

Plywood product knowledge

author: Plywood product knowledge
Plywood is a multilayer board that is cut into thin boards and then glued with adhesives. It has at least three or more layers. Generally, it is an odd number of layers. In order to ensure the bite force and glue force, the fiber direction of the two layers of veneer will be kept vertical when glued

Plywood is a three-layer or multilayer board like material made of wood segments that are peeled into veneer or sliced into thin wood by wood planing, and then glued with adhesives. Usually, odd layers of veneer are used, and the fiber directions of adjacent layers of veneer are perpendicular to each other.

Plywood is one of the commonly used materials for furniture and one of the three major wood-based panels. It can also be used for aircraft, ships, trains, automobiles, buildings and packaging boxes. A group of veneers is usually glued with each other perpendicular to the grain direction of adjacent layers. Usually, the surface and inner layers are symmetrically arranged on both sides of the central layer or the core. The slabs made of glued veneer in a crisscross manner in the direction of wood grain are pressed with or without heating. The number of layers is usually odd, and a few are even. There is little difference in physical and mechanical properties between vertical and horizontal directions. Common plywood types include plywood, plywood, etc. Plywood can improve the utilization rate of wood, which is a main way to save wood.

The usual length and width specifications are: 1220 × 2440mm, while the thickness specifications generally include: 3, 5, 9, 12, 15, 18mm, etc. The main tree species are: beech, camphor, willow, poplar, eucalyptus, etc

In order to improve the anisotropy of natural wood as much as possible and make the plywood have uniform characteristics and stable shape, two basic principles should be observed in the structure of plywood generally: first, symmetry; Second, the fibers of adjacent layers of veneer are perpendicular to each other. The principle of symmetry requires that the veneer on both sides of the symmetrical center plane of plywood should be symmetrical to each other, regardless of the wood property, veneer thickness, number of layers, fiber direction, moisture content, etc. In the same plywood, veneer of single tree species and thickness can be used, or veneer of different tree species and thickness can be used; However, the tree species and thickness of any two symmetrical layers of veneer on both sides of the symmetrical central plane shall be the same. The face and back plates are allowed to be different from the same tree species.

To make the structure of plywood conform to the above two basic principles at the same time, its layers should be odd. So plywood is usually made into three layers, five layers, seven layers and other odd layers. The name of each layer of plywood is: the surface veneer is called the surface veneer, and the inner veneer is called the core veneer; The front panel is called the panel, and the back panel is called the back panel; In the core plate, the fiber direction parallel to the surface plate is called long core plate or medium plate. When forming the cavity platen slab, the tight face of the panel and back plate must face outward.

1) It can be divided into ordinary plywood and special plywood according to its use.

(2) Ordinary plywood is divided into Class I plywood, Class II plywood and Class III plywood, which are weather resistant, water resistant and moisture resistant plywood respectively.

(3) Ordinary plywood can be divided into non sanded board and sanded board according to whether the surface is sanded or not.

(4) It can be divided into coniferous plywood and cascading plywood according to tree species

Decorative veneer

1) Decorative veneer veneer is a kind of man-made board made of natural wood decorative veneer pasted on plywood. Decorative veneer is a kind of veneer made of high-quality wood by planing or rotary cutting.

2) Features of veneer veneer veneer:

Decorative veneer veneer is one of the most commonly used materials for interior decoration. Because the decorative veneer on the surface of the product is made of high-quality wood by planing or rotary cutting, it has better decorative performance than plywood. This product is natural, simple, natural and noble, which can create a living environment with the best affinity and elegance.

3) Type of veneer veneer veneer:

Decorative veneer veneered plywood can be divided into single-sided veneer veneered plywood and double-sided veneer veneered plywood according to the decorative surface; According to water resistance, it can be divided into Class I decorative veneer veneer veneer plywood, Class II decorative veneer veneer veneer plywood and Class III decorative veneer veneer veneer plywood; According to the texture of decorative veneer, it can be divided into radial decorative veneer veneer veneer and chord decorative veneer veneer veneer veneer. Common is veneer veneer veneer veneer. The commonly used decorative veneers are birch, ash, oak, Shuiqinggang, elm, maple, walnut, etc.

4) Classification of veneer veneer veneer:

According to the Chinese standard for decorative veneer veneer veneer plywood, decorative veneer veneer plywood can be divided into three grades: superior, first grade and qualified products. This is to remind manufacturers and consumers that other grading forms do not conform to the standard of decorative veneer veneer veneer in China. For example, some manufacturers' logo grade is "AAA", which is an enterprise behavior.

5) The performance requirements of the national standard for decorative veneer veneer veneer: The current recommended standard in China is Decorative Veneer Veneered Wood based Panel (GB/T 15104-2006), which is implemented by most enterprises. The standard specifies the indexes of veneer veneer veneer plywood in appearance quality, processing precision and physical and mechanical properties. Its physical and mechanical properties include: moisture content, surface bonding strength, immersion stripping. GB 18580-2001 Limits of Formaldehyde Emission from Wood based Panels and Their Products for Interior Decoration and Decoration also stipulates the limits of formaldehyde emission from this product

Building materials board

1. It is usually made into flat rectangular building material boards of standard size (such as plywood, metal boards, concrete boards, plastic boards) and used as components of walls, ceilings or floors.

2. Thick rough boards.

3. A metal plate forged, rolled, or cast.

4. The boards include: large core board, density board, decorative panel, 3cm board, 5cm board, 9cm board, 12cm board, waterproof board, gypsum board, cement board, paint free board, paint baking board (reference: Ningbo Aijia Lvke Wood Industry Board Co., Ltd.)

Board and square sawn longitudinally from logs. Those whose width is more than three times of the thickness are called "plates"; Rectangular wood with width less than three times the thickness is called "square wood". It is a commonly used material for furniture manufacturing and civil engineering