How does a tree become a sheet of wood?

Humans have always used their wisdom to create things that didn't exist before, such as wood panels. People in the past would never have imagined how a tree could be turned into a board. Although wood panels are now ubiquitous in society, every existing item is a crystallization of human wisdom, and every product has its own inherent laws. There are also many varieties of wood panels, and different varieties have different manufacturing processes; they are not all the same as everyone else, as some might think.

Of course, if we want it to have additional functions, then we need to incorporate technologies with corresponding properties into some part of the board manufacturing process. Today, let's start with the most basic aspect of boards to understand how a tree is transformed into a board.

Taking plywood as an example, the following steps are usually required: material preparation and processing → first glue application → first cold pressing → correcting the blank → first hot pressing → first puttying → thickness sanding → second glue application → second cold and hot pressing → second puttying → surface sanding → trimming excess edges.

Material preparation and processing: As the name suggests, this involves selecting and processing standardized materials, and closely monitoring moisture content during processing to ensure that the moisture content meets the standards.

Adhesive application: Select the adhesive according to the product's environmental protection level. It is important to note that the environmental friendliness of the board is directly related to the adhesive. The prepared adhesive is evenly applied to the middle board using an adhesive application machine. The board is then assembled in one go according to the middle board-core board-middle board structure to form the substrate.

Cold pressing: A cold press is used to apply pressure to the substrate, so that the adhesive layer is pre-cured under pressure to achieve adhesion between the layers.

Correcting the blank plate: Correcting the offset of the first blank assembly to ensure that each layer of the reference edge/reference head is straight and the allowance is guaranteed. At the same time, cutting or filling and repairing the gaps in the seed plate to ensure that the surface of the substrate is flat.

Hot pressing: The material is hot-pressed using a hot press machine to fully cure it.

Scraping: Repairing and filling defects on the surface of a substrate.

Thickness sanding: Double-sided thickness sanding is performed on the medium board to ensure that the thickness of each plywood is uniform.

After the above steps, the board undergoes a second application of adhesive, a second hot and cold pressing, and a second puttying.

Surface sanding: Using a three-head sander, select a set of sanding belts with an appropriate grit to sand the surface of the plywood, making the surface flat, smooth, and uniform.

Trimming excess: Cut according to product specifications. The treated board has smooth edges with no obvious burrs.

After the above introduction, do you now have a basic understanding of the processing flow of wood panels? Do you also realize that there is so much to learn about a seemingly ordinary wood panel?