| 摘要 |
<p>In a process to manufacture chipboard, a continual fed of wood chips or fibre is scattered with a small quantity of a bonding agent (or no bonding agent) onto a non-corroding endless metal belt as this advances through a press. The wood fibre and bonding agent are pressed and heated into a fibreboard. Also claimed is a chipboard or fibreboard manufacturing press assembly with a particle scatter station over a conveyer belt feeding a press. The scatter station may feed one or more layers simultaneously. The press has a moving upper frame and a stationery lower frame with heating and cooling press plates. In the process the mixture of chips and bonding agent are dried to bring moisture content to the range 16 to 25 per cent and scattered onto the belt, where application of saturated steam and hot water spray raises the humidity to the range 25 to 35 per cent immediately prior to entering the press. The moistened chip matrix passes into the press where, during 20 per cent of the press travel, it is compressed to a maximum of 5.5 N/mm2. Water is expelled and the matrix dries under core pressure of no more than 1 N/mm2, until core moisture content falls to 5-8 per cent. In the final hardening phase the board is subjected to a maximum pressure of 3.5 N/mm2 and compressed to final dimensions and dried until the core moisture falls to 2 per cent.</p> |
