Bakelite - marine or baketalized - plywood is a composite building material. It is a rigid plate consisting of several layers of wooden veneer impregnated with special phenol-formaldehyde resins. In terms of density and properties, this polymer composition is similar to amber or ebonite. Plywood is produced by bonding veneer layers under high pressure.. The finished material has high strength, water-repellent qualities, exhibits excellent wear resistance. This allows its use in various industries.
Brands and varieties
In the production of bakelite plywood, birch or pine veneers are used. Depending on the composition of the resins and methods of impregnation, several types of marked finished material are distinguished:
- FBS. Binder resins have alcohol soluble bases. Impregnation is carried out by the method of complete immersion. The upper layers are of veneer of the first grade. Plywood is very durable.
- FBS-1. Alcohol-soluble resins are applied to veneer sheets, the bakelite content in the thickness of the plywood is less. The strength characteristics of such a material are also lower.
- FBS-1-A. In plywood of this brand, some of the sheets are coated with resins, only veneer of the second grade is used. The least durable material.
- FBV. The plywood contains water-soluble formaldehyde resins. The upper layers are completely saturated with them, the inner ones are only smeared. Such plywood requires additional coating when used on external surfaces.
- FBV-1. The material consists of veneered sheets coated with water-soluble resins. It does not have high moisture resistance, suitable only for interior decoration.
To improve moisture resistance, biostability, and to protect against exposure to chemical agents, the surface of bakelite plywood is laminated on one or both sides. The canvas becomes smooth. In the “smooth-mesh” variety, one side has a corrugated surface. It is used where anti-slip effect is required.
Specifications
Bakelitic plywood has a characteristic dark reddish brown hue. Finished material must comply with GOST 11539-83. Its grade and brand are pressed into sheets by the manufacturer along with the logo.
Standard sizes of bakelite plywood sheets:
- 5770 × 1250 mm;
- 2850 × 1250 mm;
- 2500 × 1250 mm;
- 2440 × 1220 mm;
- 1500 × 3000 mm
The thickness of the plates is from 4 to 30 mm.
The density of 1 m³ of material is about 1200 kg. The weight of one sheet depends on the thickness of the plates: 7 mm - about 25 kg, 27 mm - almost 85 kg.
Static bending strength of plywood: 78.5 MPa.
Ultimate tensile strength: about 73.5 MPa.
By strength, the material exceeds the densest wood, approaching low-alloy steel.
Bakelite plywood exhibits good fire resistance: it withstands temperatures up to +350 ° C, does not support open burning, charring under the influence of a flame.
The material is resistant to corrosion, does not decay, does not deform, does not react with aggressive chemicals, and has a dielectric property.
Bakelite plywood can be operated at ambient temperatures from –50 to +50 ° C. The material retains its technical properties for up to 15 years.
Advantages and disadvantages
Bakelite composite has many advantages over other building and finishing materials, combining the properties of natural wood and high-strength plastic:
- universality: due to its high strength, water resistance and fire resistance it can be used in many industries;
- during operation it is not damaged by harmful chemical compounds: alkalis, fuels and lubricants, kerosene, alcohol;
- environmental safety: does not emit toxic impurities into the air, can be used in interior decoration of residential premises;
- aesthetics, plywood does not require additional finishing, except in special cases;
- much lighter than steel and other materials similar in strength and wear resistance.
Bakelite plywood has few drawbacks, and they are all relative. These include:
- high specific gravity compared to other composites containing wood. Furniture and furnish from it will put pressure on the supports - this must be taken into account when using;
- high price is the main drawback. The cost of one thin sheet of grade FBS-1 is at least 2300 rubles, FBS - from 3500 rubles and above. Such types of work with its use, as disposable formwork, become simply impractical.
Stages and features of production
Bakelite was first used in production in the first half of the 20th century. This polymer, invented by American chemist Hendrick Bakeland, contained formaldehyde, phenol, and an alkaline binder. The polymer was firmly bound to the wood, giving it the necessary strength, moisture resistance, ability to withstand open fire and other valuable qualities. The structure of the fibers changed so much in the same composition with varnish that the finished material was proposed to be distinguished into a separate species - delta wood.
Bakelite plywood production includes several stages:
- immersion of prepared veneer in a container with resin or lubrication with plasticizer on both sides of it;
- stacking the impregnated sheets in such a way that the fibers of each layer are perpendicular to each other;
- pressing in chambers at a temperature of +270 ° C under a pressure of 4 MPa;
- cooling;
- additional surface treatment: grinding, lamination;
- cutting and cutting plates according to specified parameters.
Application
The physical and technical parameters of the baketalized plywood are exceptional. The scope of its application is wide:
- Building sector. Floating docks, locks, water locks are erected from the material, they are used for reusable formwork, wall partitions, awnings. Light constructions, pantries, garden houses are erected from bakelite plywood. In regions with a warm climate, walls of residential buildings are built from it. It can be used for interior decoration of residential premises - ceilings, walls and floors. Bakelite material is a reasonable choice in hot humid climates, in regions with frequent rainfall and large seasonal temperature differences.
- Engineering and automotive industry. Cabs, vans, floors are built from the plates, used for the inner lining of automobile interiors, various mechanisms.
- Shipbuilding. No wonder this type of plywood is also called marine. Bakelite, which imbues veneer, can withstand prolonged exposure to salt and fresh water. The material is used for cladding decks of ships, the construction of boats and light boats.
- Plywood is well suited for the manufacture of stands, decorations, technical models, various visual aids.
What determines the price
The cost of the finished material consists of many parameters. Among them:
- Brand of plywood. Alcohol-soluble resins used in PBS grades are more expensive. Highly valued and birch veneer in the composition of the plates. The FBS-1-A and FBV-1 grades will cost cheaper than the rest, where second-grade wood is used, smearing, and not soaking it with bakelite.
- Sheet format. The cost of plywood depends on the thickness and size directly. Canvases of 27, 30 mm having such parameters will cost more.
- Manufacturer country. Russian-made material will differ in price from Chinese, the most cheapened plywood.
The size | Price per sheet (rub.) |
2440x1220x7 | 2085 — 2710 |
2440x1220x10 | 2975 — 3840 |
2440x1220x12 | 3570 — 4590 |
2440x1220x15 | 4465 — 5680 |
2440x1220x18 | 5360 — 6780 |
2440x1220x21 | 6250 — 7910 |
The calculation of the final cost must be done taking into account the required qualities of the material. Thin sheets with moderate moisture resistance and shock resistance can be suitable for interior decoration of room walls. For outdoor work or self-construction of the boat, it is better to prefer high-quality thick plates to ensure maximum service life.