Block Board refers to a special plywood made by gluing and pressing wood strips or hollow boards as core boards, and covering two or more layers of plywood on both sides. The characteristics of blockboard are mainly determined by the core board structure. It is widely used in furniture manufacturing, sewing machine table tops, carriages, ships, etc. and construction industry. There are many kinds of core boards, such as poplar, birch, pine, paulownia, etc. Among them, poplar and birch are the best, with dense texture, neither soft nor hard wood, strong nail holding force, and not easy to deform. The texture of paulownia is very light, soft, absorbs a lot of water, has poor nail holding force, and is not easy to dry. During the use of the board, when the water evaporates, the board is easy to crack and deform. Pine wood has a hard texture, is not easy to press, has a poor splicing structure, poor nail holding force, and a large deformation coefficient.