Method and device for preheating a pressed material mat in the course of the production of wood-based panels

摘要

The invention relates to a method for preheating a pressed material mat (14) scattered on an endless continuously circulating forming belt (6) in the course of the production of wood-based panels, wherein microwaves of one or both pressing surfaces sides are irradiated into the press-material mat (14) for preheating the pressed material mat (14) are pressed and the pressgutmatte (14) after being transferred to a continuous press (1) using pressure and heat and cured. The invention consists in that microwaves in a frequency range of 2400-2500 MHz are used for heating the pressed material mat (14), wherein the microwaves for each press surface side consist of 20 to 300 microwave generators (26) with magnetrons (20) of a respective power of 3 to 50 kW are generated. Furthermore, a device for heating pressed material mats (14) is presented in which in a continuous furnace (4) per surface side 20 to 300 microwave generators (26) with magnetrons (20) of a power from 3 to 50 kW and with a frequency range of 2400-2500 MHz are arranged.