1. What are the commonly used furniture panel materials on the market? What are their characteristics?
The commonly used furniture panel materials on the market include OSB(Oriented Strand Board), MDF (medium-density fiberboard), plywood, Block board, solid wood board, and prefinished board. Generally speaking, panel materials can be categorized into engineered wood and natural wood. Engineered wood is cheaper but may have formaldehyde pollution, while natural wood has minimal formaldehyde pollution but is relatively expensive.
2. Which materials originate from North America, Europe, and Africa respectively?
North American: In comparison, they are not considered dominant, but the supply and demand are relatively stable. Hardwood species include red oak, white oak, hickory, black walnut, cherry, maple, boxwood, and red gum. Softwood species include fir, SPF, yellow pine, Douglas fir, and white pine, with large quantities available. Red oak has seen significant price increases in the past couple of years.
European: European ash is the most mature, and in recent years, European oak and red gum have slowly been entering the market. European softwood species, such as Scots pine, spruce, and red pine, have slightly higher prices compared to Chinese pine and New Zealand pine. The most common species are red gum, oak, birch, elm, elm-leafed cherry, and various types of pine.
African: Central African countries like Gabon, Cameroon, Congo, and Zaire continuously supply large-diameter logs such as rosewood, red rosewood, sapele, teak, and tali, which are consistently imported into China.
3. What are the specifications for wood panels? How are they categorized?
Medium-density fiberboard (MDF): Also known as fiberboard, it is a type of engineered wood panel made from wood fibers or other plant fibers, combined with urea-formaldehyde resin or other suitable adhesives. It is categorized into high-density MDF, medium-density MDF, and low-density MDF. The common specifications for MDF are 1220mm2440mm2mm~30mm, and special sizes can be customized.
Blockboard: It is formed by glue-pressing and splicing two pieces of veneer together. Blockboard is cheaper than thin core board, although it has lower bending and compressive strength, it exhibits higher transverse bending strength. The common specifications for the big core board are 2440mm*1220mm, with thicknesses generally ranging from 3mm, 5mm, to 9mm.
OSB(Oriented Strand Board): OSB, also known as chipboard, is a thin sheet made from wood chips as the main raw material, mixed with adhesive and additives, and pressed together. It is divided into extruded particleboard and flat-pressed particleboard. The common specifications for particleboard are 1220mm*2440mm, with special thicknesses ranging from 25mm to 45mm.
Melamine board: Melamine board is a decorative panel made by laminating melamine-impregnated decorative paper onto plywood, medium-density fiberboard (MDF), or hardboard. Melamine board is available in the common size of 2440mm*1220mm.
Plywood: Plywood is made by hot pressing three or more layers of 1mm thick veneers or thin sheets together. It is widely used in the production of furniture. Plywood comes in common thicknesses of 3mm, 5mm, 9mm, 12mm, 15mm, and 18mm.
4. What are the grades for wooden boards and what are the criteria for distinguishing them?
Environmental Grade:
The commonly used environmental grade for wood is the E grade, which is further divided into three levels: E0, E1, and E2.
E0 grade (formaldehyde emission ≤ 0.5mg/L)
E1 grade (formaldehyde emission between 0.5mg-1.5mg/L)
E2 grade (formaldehyde emission greater than 1.5mg/L)
Board Grades:
Wood boards are categorized into A-grade and B-grade based on criteria such as material, surface smoothness, grain patterns, knots, decay, wormholes, cracks, blunt edges (not applicable for solid wood), bending, diagonal grain (or twisting), etc. The grading criteria are stricter for A-grade compared to B-grades.
5. What are the common defects in wooden boards and how can they be identified?
Wood is an anisotropic and heterogeneous material, meaning that different parts of the wood have varying performance characteristics, particularly in terms of physical and mechanical properties. Non-uniform expansion and contraction can lead to increased deformations, and the differential strength properties can result in wood cracking.
Wood is hygroscopic, meaning it readily absorbs and releases moisture. This natural moisture absorption can cause swelling and drying shrinkage, affecting the dimensional stability of wood products and making them prone to deformation.
Wood is a natural high-molecular-weight organic polymer, making it susceptible to infestation by insects and fungi (such as molds and wood-rotting fungi). This vulnerability to pests and decay can lead to wood degradation, damage to wood products, and significant losses in terms of manpower, resources, and finances.
Wood drying can be challenging. It is essential to use properly dried wood for manufacturing wood products. Wood drying requires a significant amount of energy and if not done carefully, can result in defects such as warping and cracking, causing unnecessary losses.
Wood is highly flammable. In places where wood is extensively used, it is crucial to implement reinforced fire safety measures.