Changes in wood-flake properties in relation to heat, moisture, and pressure during flakeboard manufacture

In an attempt to relate different pressing parameters to changes in test flake properties, eight hot-press cycles were used in the manufacture of 24 flakeboard panels, with 2 levels each of platen temperature, initial mat moisture content, and press closing time. Temperature and gas pressure occurring at the face and core of the mat, along with platen pressure, were recorded throughout the press cycles. Data is presented graphically as a function of press time. Face and core equilibrium moisture content conditions throughout the press cycle were estimated for each panel based on corresponding temperature and gas pressure information. Time-integral data on temperature, gas pressure, and platen pressure were determined. Simple linear regressions were performed in an attempt to relate the actual test flake environment to changes in properties.

Two hundred and fifty yellow-poplar (Liriodendron tulipifera) test flakes were consolidated within the face and core of flakeboard mats and recovered. Their individual pre- and post-pressing thickness and specific dynamic bending modulus values were determined and compared with respect to changes in pressing parameters. Platen temperature, initial mat moisture content, and test flake location within the mat were all involved in significant two-way interactions in their effects on flake properties.