Study on effects of preheating enhancement process on the strength of ultra-thin fiberboard slabs by orthogonal analysis

Abstract

Ultra-thin fiberboard (UTF) is a wood-based panel produced through a hot-pressing process. UTF can be directly applied as a decorative veneer on curved walls or panels, significantly expanding the range of applications for fiberboard and increasing its added value. Due to its thickness, UTF is flexible and malleable, making it a suitable alternative to wood veneer as the outer layer of plywood. Additionally, UTF effectively mitigates the cracking commonly caused by the anisotropy of wood veneer. In the UTF production line, there is a gap between the preheating enhancement machine and the continuous-flat press machine. If the ultra-thin fiberboard slab (UTFS) lacks sufficient strength, it is prone to collapsing and fracturing in this gap, leading to production breakdowns. To address this issue, UTFS is preheated prior to continuous hot-pressing to enhance its strength. This study evaluated the effects of preheating temperature, adhesive dosage, and fiber moisture content (MC) on UTFS strength using orthogonal analysis. The results indicated that the optimal UTFS strength was achieved when the preheating temperature was set at 85 °C, the adhesive was 5%, and the fiber moisture content was 12%. This work provides an evaluation basis for adjusting the parameters of the preheating enhancement process and offers theoretical guidance for the industrial production of ultra-thin fiberboard.