Production technology of waterproof plywood

Abstract

The invention provides a production technology of a waterproof plywood and relates to the technical field of plywood production. The production technology comprises the following steps: peeling barks from logs, annularly cutting the logs into wood sheets, and then air-drying; applying an adhesive, and coating the wood sheets with the adhesive which comprises the following components in parts by weight: 100-120 parts of UF resin, 10-20 parts of coking coal oil, 10-20 parts of metallic soap, 10-20 parts of alkanolamide, 6-10 parts of a curing agent, 30-50 parts of filler, 5-9 parts of a modifier and 90-110 parts of water; conveying the wood sheets onto a conveyor belt, softening the wood sheets by using a heating device to heat the wood sheets to 60-80DEG C, and then, planishing the wood sheets through compression rollers; replenishing the adhesive; assembling a blank; pre-pressing; trimming and hot-pressing; filling putty; and sawing edges and molding so as to obtain the polywood. The production technology is short in pre-pressing and hot-pressing time and high in production speed. The waterproof plywood is small in internal stress, cannot easily come apart or deform as the adhesive is good in thermosetting property, high in viscosity, high in strength, good in durability and is not prone to going bad, and is good in waterproof effect.

Description

Technical field: [0001] The invention relates to the technical field of plywood production, in particular to a production process of waterproof 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 forming of plywood. The strength of the plywood after forming is insufficient, and the waterproof effect of the plywood adhesive is poor. The plywood prod...

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 forming of plywood. The strength of the plywood after forming is insufficient, and the waterproof effect of the plywood adhesive is poor. The plywood produced is easy to crack after rain, resulting in a low service life.

In addition, in the prior art, the wood chips are generally not very smooth, and are all curled, especially for some wood chips of hard trees, the curled wood chips are not easy to lay and arrange, and are not convenient for later stage suppression. Forming, and the gluing in the prior art is one-time gluing, which is not only uneven, but also the rubber material is too dry before pressing, which is not conducive to pressing and forming. Slow, and the internal stress is also large, easy to deform and open glue