What Is a Plywood Saw?

Plywood is a three-layer or multi-layer board-like material formed by rotating a wood segment into a veneer or a wood plane and then cutting it into thin wood. The fiber directions are glued perpendicular to each other.

In order to improve the anisotropic properties of natural wood as much as possible, so that the characteristics of plywood are uniform and the shape is stable, general plywood must adhere to two basic principles in structure: one is symmetry; the other is that the adjacent veneer fibers are perpendicular to each other. The principle of symmetry is that the veneers on both sides of the symmetric center plane of the plywood should be symmetrical to each other regardless of the wood properties, veneer thickness, number of layers, fiber direction, moisture content, etc. In the same plywood, veneers of a single tree species and thickness can be used, and veneers of different tree species and thicknesses can also be used; however, any two layers of veneer trees that are symmetrical to each other on both sides of the center plane of symmetry must have the same thickness. The backplane is not allowed to be of the same tree species.

To make the structure of plywood meet the above two basic principles at the same time, the number of layers should be odd. Therefore, plywood is usually made into three layers, five layers, seven layers and other odd layers. The names of the plywood layers are: the surface veneer is called the surface board, and the inner veneer is called the core board; the front board is called the panel, and the back board is called the back board; in the core board, the fiber direction is parallel to the table board It is called long core board or middle board. When forming the cavity platen slab, the face plate and back plate must face tightly outward.

In order to make full and reasonable use of forest resources to develop plywood production and make the best use of it, China s newly formulated national standard (draft for approval) divides plywood into coating plywood based on the use of plywood. Furniture, sewing machine tableboards and various electrical enclosures, etc.), plywood for decoration (used as decoration materials for buildings, furniture, vehicles and ships), general plywood (suitable for packaging, padding and other uses) and thin wood decoration Plywood (used as a high-grade decorative material for construction, furniture, vehicles, ships, etc.), the type of plywood is further divided into:

(1) Class I (NQF)-weather resistant, boiling water resistant plywood. This type

Plywood is durable, resistant to boiling or steam, and can be used outdoors.

(2) Type II (Ns)-water resistant plywood.

It can withstand cold or short-term hot water immersion, but it is not resistant to boiling.

(3) Class III (Nc)-non-moisture-resistant plywood.

In 1812, the French mechanic obtained the first patent for a veneer saw. By 1825, this type of veneer saw could not be used in industrial production, and it was improved and manufactured in Hamburg, Germany. The first veneer planer was developed by the French Charles Picot and was patented in 1834. It took nearly 30 years to use it for industrial production. The development of the plywood industry benefits from the invention and application of the veneer rotary cutting machine. There are several statements about the invention of the first rotary cutting machine. The first rotary cutting machine was invented in 1818; in 1819, the Russian professor Fesel Rotary cutting machine, then called thin wood planer; Some people think that the rotary cutting machine was invented by British engineer Fevilear; In 1840, John Dresser won the US rotary cutting machine patent No. 1758, Carand in France in 1844 Obtained another patent for rotary cutter. In the middle of the 19th century, Germany established the first veneer manufacturing plant. Most of the rotary cutting machines were French, and Germany also imported American-made rotary cutting machines. After 1870, the A. Roller company in Berlin, Germany produced a relatively simple rotary cutter. Before the First World War, the continuous development of rotary cutter technology promoted the rapid development of the plywood industry. In the 1890s, the quality of plywood had been greatly improved. Since then, the market has gradually opened up, and the production of plywood has developed rapidly. Many plywood factories have been established. In the United States, plywood did not become an official trade name until World War I ^[1]

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

2) Features of decorative veneer veneer plywood:

1. It is usually made of standard rectangular flat building material board (such as plywood, metal plate, concrete plate, plastic plate) as a wall, ceiling or floor member.

2. Thick rough boards.

3. Forged, rolled or cast metal sheet.

4. The plates are: large core board, MDF decorative panel, three centimeter board, five centimeter board, nine centimeter board, twelve centimeter board, waterproof board, gypsum board, cement board, paint-free board, and paint-free board (Reference: Ningbo Aijia Green Wood Board Co., Ltd.)

A collective name for boards and squares that are longitudinally sawn from logs. A plate with a width of more than three times its thickness is called a "panel"; a rectangular timber with a width less than three times its thickness is called a "square". Is commonly used in furniture manufacturing, civil engineering and other materials.

The rapid growth of China's economy has become a strong traction to promote the demand of plywood market; a large number of fast-growing and high-yielding forest wood in North China, East China and the middle and lower reaches of the Yangtze River have flooded into the market, and the continuous supplementation of foreign high-quality broad-leaved wood has contributed to the continuous development of China's plywood industry. Provide abundant raw materials; sufficient human resources are also important factors in the cost accounting of China's development of plywood industry compared with other plywood producing countries. The quality of China's plywood products has also been greatly improved, and it has become increasingly competitive in the international market. China is not only a large plywood exporter, but also the world's largest plywood producer.

From January to December 2006, China's plywood manufacturing industry realized a cumulative total industrial output value of RMB 75,819,437,000, an increase of 39.83% over the same period in 2005; realized cumulative product sales income of RMB 72,163,513,000, an increase of 39.25% over the same period in 2005; and a cumulative total profit of 3,198,494,000 Yuan, an increase of 60.41% over the same period in 2005.

From January to November 2007, China's plywood manufacturing industry realized a cumulative total industrial output value of 101,828,484,000 yuan, an increase of 48.27% over the same period last year; a cumulative product sales income of 96,534,099 thousand yuan, an increase of 48.87% over the same period last year; realized cumulative profits The total amount was 4,732,364,000 yuan, an increase of 70.26% over the same period of the previous year.

Although China's plywood has developed rapidly, it still encounters anti-dumping complaints from the European Union and other importing countries. Therefore, China's plywood enterprises and industry organizations must strengthen communication with importers, strengthen corporate self-discipline, and regulate the export operation order. With the expansion of China's infrastructure construction and the development of the Midwest, the market potential of plywood is huge.