| 摘要 |
Continuous production of wood-based board comprises: (1) forming on a conveyor belt that serves as a mold, a mat of starting material (wood particles) that has been treated with binder to form a material for compression (A); and (2) passing this between the upper and lower rotating steel bands of a continuous press (with application of heat and pressure) to form, by hardening, a board strand or endless strip of product. The new feature is that the temperature and moisture content of the wood chips and (A) are controlled according to a specific regime. The regime comprises: (i) the particles are kept at below 40 deg C before gluing and up to preheating, and after gluing, the moisture content of (A) is below 7.5%; (ii) (A) is heated in a short pre-heating section (X) to 85-110 deg C in less than 30 sec, while moisture content is increased to 8-13%, using steam or a steam-air mixture; (iii) during pre-heating, a quick-reacting adhesive-accelerator-hardener combination, or a very reactive adhesive, is incorporated into (A) so that hardening starts immediately after leaving (X) (with achievement of a temperature over 95 deg C in the middle of the mat during the continuous pressing stage, hardening is complete within 20 sec).
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