Production process for plywood

Abstract

A production process of plywood, which relates to the technical field of plywood production, comprising the following steps: peeling a log, cutting it into chips, and then drying it in the sun; gluing, and applying an adhesive to the wood chips, and the adhesive consists of the following in parts by weight: 80-100 parts of urea-formaldehyde resin, 20-40 parts of nitrocellulose, 10-20 parts of polyphenylene sulfide, 6-10 parts of curing agent, 30-50 parts of filler, 5-9 parts of modifier and 80-100 parts of water; keep the wood chips on the conveyor belt, heat and soften the wood chips through the heating device, the heating temperature is 60-80 ℃, and then flatten the wood chips by pressing rollers; glue repair; billet formation; pre-pressing; trimming And hot pressing; filling putty; sawing edge forming, get plywood. The present invention has short pre-pressing and hot-pressing time, fast production speed, small internal stress, and is not easy to unglue and deform. The adhesive has the advantages of good thermosetting, high viscosity, high strength, good endurance and not easy to deteriorate.

Description

Technical field: [0001] The invention relates to the technical field of plywood production, in particular to a production process of plywood. Background technique: [0002] Plywood is a three-layer or multi-layer board-like material that is made of wood sections that are peeled into veneers or sliced ​​into thin wood, and then glued with adhesives. Usually, odd-numbered veneers are used, and adjacent layers of veneers are used. The fiber directions are glued perpendicular to each other. The adhesives used in the production of plywood generally use more thermosetting adhesives. Some adhesives have poor thermosetting properties, and the thermosetting process takes a long time, which is called insufficient viscosity. Especially when the temperature is high, the viscosity is greatly reduced. It is beneficial to the molding of plywood, and the strength of plywood after molding is insufficient. In addition, in the prior art, wood chips are generally not very smooth, and they are ...

AI Technical Summary

Problems solved by technology

The adhesives used in the production of plywood generally use more thermosetting adhesives. Some adhesives have poor thermosetting properties, and the thermosetting process takes a long time, which is called insufficient viscosity. Especially when the temperature is high, the viscosity is greatly reduced. It is beneficial to the molding of plywood, and the strength of plywood after molding is insufficient. In addition, in the prior art, wood chips are generally not very smooth, and they are all curled, especially for some wood chips of hard trees. It is not convenient for tiling arrangement, and it is not convenient for later pressing and forming, and the gluing in the prior art is one-time gluing, which is not only uneven, but also before pressing, the sizing material is too dry, which is not conducive to pressing and forming, and the hardness of wood chips is high , the later pre-pressing and hot-pressing time is long, the speed is slow, and the internal stress is also large, easy to deform and open glue