Today, Hot Press Machine Supplier will share with you the issues related to plywood.
Plywood Hot Press Machine
First, what are the disadvantages of poor quality plywood:
1. Low bonding strength: Mainly caused by poor quality of the glue. Plywood Hot Press Machine's hot-pressing conditions are not well controlled, such as low hot-pressing temperature, insufficient pressure and too short glue pressing time. Veneer moisture content is too high, the amount of glue applied is insufficient, the quality of the veneer is poor, and the aging time is too long or too short, which will also reduce the bonding strength.
2. Bubbling and partial glue opening: The reason is that the speed of pressure reduction is too fast, the glue pressing time is insufficient, the moisture content of the veneer is too high, there are blank spots during coating, or there are inclusions, dirt on the veneer, or the use of pine veneer caused by high temperature.
3. Plywood warping: It is caused by the large internal stress of the plywood. The reason is that the moisture content of the back panel is inconsistent, the veneer of different tree species is unreasonable, the veneer is twisted, the temperature of the individual hot-pressed plates is not enough, and the boards are stacked unevenly.
4. Corner open glue: The cause of this defect is the insufficient pressure caused by the wear of the corners of the pressure plate. When loading the board, the slab is placed skewed and pressure is uneven. The Veneer Rotary Cutting Machine has insufficient pressure during spin cutting, weak bonding force, lack of glue at the corners, premature drying of the glue, and low local temperature of the platen.5. Penetration: The reason is that the glue solution is too thin, the amount of glue is too large, the cracks on the back of the veneer are too deep, the moisture content of the veneer is too high, and the aging time and pressure are too large.
6. Core board stacking and separation: The reason is that the gap is too large or too small when the cores are manually used to arrange the cores, the core boards are misaligned or overlapped, and the edges of the parts are uneven.
So how does plywood identify authenticity?
How to distinguish between genuine and false plywood
1. Observe the toughness of the wood. The eucalyptus willow core has higher toughness than the poplar core. When it is turned, the eucalyptus core plywood is not easily twisted, and the poplar core plywood will appear soft.
2. Differentiate by color. The natural colors of these two materials are very different, and the fakes are only painted on the surface of the wood, so the interior of the wood is still the original color. It can be distinguished by peeling off the surface. The poplar is white and the eucalyptus core is brown-red.
3. Amount of tritium. The density of willow eucalyptus and poplar cores are very different. Under the same volume, willow eucalyptus core is much heavier than poplar core. You can feel it just by comparing it with your hands.
How to distinguish between good and bad plywood?
1. The plywood should be clear in wood grain, smooth and smooth on the front, not rough, and flat.
2. The appearance of good plywood is free from damage, knots, and bruises. Pay attention to the consistency of color and the overall feeling of wood grain.
3. Plywood should be free from defects such as breakage, bump damage, insect residue, nail holes, dead knots, and burr grooves.
4. Some plywood is made of two veneer adhesive patches with different textures, so you should pay attention to the selection, the plywood joints should be tight and there is no unevenness. Especially one plywood should not have two different patterns, otherwise it will hinder reasonable use, cause waste, and affect the aesthetics of furniture.
5. If you can smell a strong pungent odor, it means that there are more harmful components in plywood. This kind of plywood is not only of low quality but also harmful to human body.
The above are the related issues of plywood, I hope to help everyone.