Almost every process in the production of plywood affects the quality of gluing plywood together to varying degrees. In order to facilitate the grasp, the following aspects are summarized:
1. Adhesive quality: performance of the synthetic resin adhesive for glue, the combination of various components and the glue adjustment process, etc. In recent years, a lot of domestic research work has been done on the components of glue used for 2400 x 1200 x 12mm plywood and the glue mixing process. This not only saves many chemical raw materials, but also reduces 12mm plywood price and improves 12mm plywood structural performance. This is a manifestation of technological progress. In the production, only the synthetic resin used has good performance, sufficient bonding strength, reasonable distribution ratio of each component of the adhesive, stable performance of the prepared adhesive, suitable resin content and viscosity, and a long enough active period to ensure normal operation and product items, the indicators meet the requirements.
2. veneer quality: especially its surface condition has a great influence on the bonding strength. The quality of the veneer plywood should be paid attention to during the preparation of the wood section and the various processes of the veneer peeling. The 3mm wood sheet softening treatment should be carried out well, and the peeling conditions should be controlled to make the various indicators of the veneer at the best value. At the same time, attention should be paid to the veneer moisture content, rate and flatness.
3. Plywood gluing: Before gluing, you should pay attention to mastering the amount of glue and slab aging. If the amount of glue is too large, the cost will be high; and if the glue layer is too thick, the internal stress will increase and the glue will penetrate easily; if the amount of glue is too small, it is not conducive to the infiltration of the glue and the glue layer will be incomplete. The aging time should be appropriate and change reasonably with climate change. It is necessary to realize the integration of the core board and reduce the stacking and separation of the core board. It is necessary to pay attention to the speed of pressure reduction, especially when there is more water in the slab.
In addition, new technologies and new equipment are adopted, such as the use of high-efficiency jet veneer dryers, core board stitching machines, and core board leveling machines to achieve continuous operations of sizing, blank assembly, pre-pressing, and hot pressing, and mechanized loading and unloading, quickly closing the hot press, etc. This can accurately control the process conditions, so that the high grade plywood is more assured.