What are the specifications of plywood?
The density of plywood is greater than that of wood of the same kind. The greater the unit pressure during plywood bonding, the greater the density of plywood. Because wood is easy to produce plastic deformation at high temperature, the compression ratio of hot pressing bonding is larger than that of cold pressing. Because plywood is made up of interlaced veneers, the thermal conductivity of plywood is lower than that of the same kind of wood.
The physical and mechanical properties of plywood can be explained by moisture content, density, thermal conductivity and bonding strength. The international standard organization on the production of ordinary plywood, from the structure, finished product moisture content, quality of 3 aspects of the provisions: 1. The texture of the veneer of the adjacent layers should be at right angles to each other; each layer is symmetrical with respect to the central layer; the thickness of each layer is the same; the surface and the back panel face outwards. Moisture content. Between 12~14% (according to China's national standards, the absolute moisture content of type I and II plywood is not more than 13% on average, and moisture content of plywood III and IV is not more than 15%). Quality. The finished product shall have rectangular straight edges and distinct edges and corners. The minimum number of plies per nominal thickness shall comply with the relevant regulations.
The classification of many kinds of plywood, plywood by species can be divided into softwood and hardwood plywood plywood; use can be divided into ordinary plywood, plywood, cement formwork structure plywood, fireproof plywood and special plywood etc..
