Wooden packaging boxes and pallets are used in a wide range of applications. In this work, LVL from the same source and batch were used as the base material. After dynamic detection and grading, they were divided into two grades (A and B), according to their differences in elastic modulus. The packaging boxes and pallets of the same specifications were designed and manufactured as the research objects. Four mechanical properties studies and related analyses were performed. The three mechanical tests showed different deflection values of the two packaging boxes A and B, and the maximum error was 6.93%. In the rotational edge drop test, the edges of the nether end rails of the two grades of LVL boxes were damaged to varying degrees. Additionally, the nails at the connection between the middle longitudinal beam and the bottom plate also appeared to be pulled out, and the parts made of B-grade LVL were more obvious. The results show that the dynamic detection and quality grading for LVL can effectively distinguish the material grade. The grading results were consistent with the mechanical properties of the LVL packaging boxes and pallets of corresponding grades, which are suitable for use in production lines.

In order to improve the fire resistance, water resistance and wear resistance of ordinary plywood products in the wood processing industry, three composite structures of plywood products S1, S2 and S3 were designed in this paper, and a reasonable production process was proposed. Through the physical and mechanical properties and fire resistance testing and technical and economic analysis, the applicability of composite plywood was evaluated. The results of the study showed that the physical mechanics of the three kinds of composite structure plywood met the standard requirements, and their fire resistance was far better than that of ordinary plywood. Among them, the S1 structural board had the best overall physical and mechanical properties. The S3 structural board showed the best fire resistance, which was about 1.9 times more than that of ordinary plywood, and the added cost was the lowest. The thin cork board added to the S2 structural board had poor fire performance since the air in the cork board cavities had a certain combustion-supporting effect, which inhibited the fire resistance of high-pressure laminate (HPL) layer. Moreover, the additional cost of the S2 board was the highest, and its comprehensive performance was the worst. The S3 structural plywood product composed of HPL fireproof board with a thickness of about 1 mm in the surface layer and ordinary plywood with a thickness of about 12 mm in the core layer was the most cost-effective product, which could meet the needs of various fields such as construction, home furnishing, decoration and transportation.

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