What are the types of plywood materials? What are the characteristics of commonly used plywood?

Plywood is a slab of eucalyptus, birch, eucalyptus, ash, nanmu, poplar, etc., which is then softened by steaming and cutting into large sheets along the annual rings. After being dried, the fibers of the adjacent two veneers are perpendicular to each other, and the fibers of the adjacent two veneers are perpendicular to each other, and then heated and glued to form an artificial plate. In order to eliminate the shortcomings of wood anisotropy and increase the strength, the thickness of the veneer, tree species, water content, grain direction and production method should be the same when producing plywood. The number of layers is generally odd, such as three, five, seven, nine. Thirteen plates, etc., to balance various internal stresses. Plywood is mainly used for the back and bottom of wooden products in decoration. Due to the thickness and variety, the texture is flexible. It is easy to bend, and can also be used with wood core board for the delicate structure, which makes up for the defect of uniform thickness of wood core. Or used to make partitions, curved ceilings, decorative door panels and wall skirts. The appearance of the plywood is flat and beautiful, the width is large, the shrinkage is small, it can be bent, and can be arbitrarily processed into various forms. Specifications length × width is 2440mm × 1220mm, thickness is 3 ~ 22mm variety. The price of common 9mm thick plywood is 50~60 yuan/sheet.

When purchasing plywood, the bill of materials should be listed. Due to different specifications and thickness, the parts used are different, so avoid waste. Observe the front and back sides of the plywood. The bar and patch should not be seen. The cross-section should be carefully observed. The veneers should be evenly stacked. There should be no staggering or cracking, and there should be no signs of decay and deterioration. Lifting the side of the plywood with both hands can feel whether the plate is flat and even, and whether there is tension and bending tension.