Coniferous plywood: characteristics, manufacturing, marking. Plywood PSF

Plywood is a building material made from layers of wood (veneer) joined together.

Characteristic

The main properties of plywood depend on the wood from which it was made. Already from the name it is clear that coniferous plywood is made of coniferous species (spruce, pine). The veneer layers are arranged so that the fibers are perpendicular to each other.

Main characteristics of the material:

• Relatively low cost.
• A small weight of material.
• Withstands temperature changes.
• Moisture-proof.
• High strength due to the presence of layers.
• Easy to use (you can saw, drill, etc.).
• Absorbs noise.
• It serves as a layer of thermal insulation.
• Wood impregnated with natural resins, which makes the material resistant to the appearance of mold and fungi.
• Sufficiently resistant to aggressive environments.
• Aesthetically beautiful due to the manifested structure of wood.

Methods of making plywood

There are three ways:

1. Sawing. For the production of veneer, the wood is cut into strips up to 5 mm in thickness. With this method, raw materials are used uneconomically.
2. Planing - a more economical method, which allows to obtain a veneer with a thickness of 3.5 mm.
3. Plywood grouting is the method by which veneers with a thickness of 1.2 to 1.9 mm are obtained.

Which plywood is better: birch or coniferous?

For production, different types of wood can be used : coniferous and deciduous species. The properties of the material obtained depend, of course, on the raw material. Each species has its advantages and disadvantages.

Plywood of coniferous species consists of a smaller number of layers. The material made of larch is more durable, resilient and wear-resistant. For more durable objects it is better to choose plywood from birch.

Veneer made of birch has a light tint and a poorly expressed texture. Coniferous rocks, on the contrary, are darker and have a beautiful clearly expressed pattern.

Coniferous wood is impregnated with natural resins. Due to this, the materials made from them are less exposed to mold and fungi. Coniferous plywood is a relatively cheap building material.

Marking

The quality of the material depends largely on the glue used to join the veneer layers. Depending on this, the coniferous plywood has several markings:

• The FBA is the lowest quality brand. It is made with the use of albuminasein glue. This makes it an environmentally friendly material. But this material can not stand the moisture. Apply it only where there is protection against ingress of water.

• PSF - the most popular brand, made with phenol-formaldehyde glue. It is strong enough and waterproof.

• FSF-TV differs from the brand FSF impregnation with flame retardants. Due to this, the coniferous plywood of this species has a low flammability.

• FC is produced with the help of urea glue, which makes the material more hygroscopic. Used for the manufacture of furniture, containers, internal structures.

• FB is moisture resistant, not exposed to aggressive environment. You can use it even under water. This is achieved by combining the layers with bakelite glue and impregnation with the same varnish.

• BS - aircraft plywood, received its name due to its use in aviation and shipbuilding. Veneer is glued together with bakelite alcohol-soluble glue. Coniferous plywood of this marking is waterproof, strong, flexible and resistant to aggressive environment.

• The BV has the same properties as the BS. The only difference is that the material of this marking is afraid of moisture (it is made with the help of water-soluble glue).

All kinds of plywood differ surface finish. Depending on this, it can be of three types: unpolished (NS), with one-sided grinding (Ш1) and ground on both sides (Ш2).

FSF

Coniferous plywood FSF is most popular in the construction of civil and industrial facilities. Its resistance to water is obtained by impregnating layers with poorly soluble formaldehyde resins. After impregnation, the veneer layers are poisoned under the press at a high temperature.

It is permissible for GOST to separate a certain amount of formaldehyde and phenol compounds. This makes it difficult to use plywood directly inside the premises.

Sheets of PSF plywood have standard dimensions: 1.22 x 2.44 m, 1.25 x 2.50 m, 1.525 x 3.0 m, 1.525 x 1.525 m. Simultaneously, the thickness varies within the range of 4-30 mm.

The plywood of coniferous breeds of mark ФСФ has received wide application. The main directions of its use are:

• Temporary constructions during construction.
• Sheathing of objects.
• Like overlapping under the roof.
• When building cars, cars and ships for their plating.
• For the creation of garden and country furniture.
• For the construction of the formwork (the material can be used repeatedly).
• As raw materials for the production of other materials.

Plywood is an inexpensive and high-quality building material that has been popular in the market for a long time.