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根据企業干燥室的实际經驗和試驗所的試驗結果,一般用的热空气或焰气加热木材的干燥室,在80～85℃的溫度下是不可能保証高速干燥的。欲加速木材的干燥过程,只有在采用高溫空气或焰气并在高速气流(1.5～2公尺/秒)之下才能达到。在此种情况下鋸材的干燥加快,但如果空气的相对湿度过低,則被干燥的材料必然会發生隙裂与翹曲。用高溫低湿的空气或焰气进行干燥的結果,鋸材將产生很大的內应力,形成劈裂与翹曲,这是因为此时木材外部的水份虽迅速排出,但并不能同时促使木材中部的水份迅速蒸發。如果木材及其水份的溫度保持較低,就会妨害干燥过程的加速,而当水份的吸着力减小时,則可达到良好的干燥效果,因此在被干燥材料断面的水
According to the actual experience of the company’s drying room and the test results of the test, the general hot air or flame heat heating the drying chamber of the wood cannot guarantee high-speed drying at a temperature of 80-85°C. To speed up the wood drying process, it can be achieved only with high-temperature air or flame and high velocity air flow (1.5-2 m/s). In this case, drying of sawn timber is accelerated, but if the relative humidity of the air is too low, the material to be dried will inevitably undergo cracking and warpage. As a result of drying with high-temperature, low-humidity air or flame, the sawn timber will generate a great deal of internal stress, forming chapped and warped. This is because the moisture outside the wood is quickly discharged, but it does not promote the wood at the same time. The water in the middle quickly evaporates. If the temperature of the wood and its moisture is kept low, it will hinder the acceleration of the drying process, and when the suction of the water is reduced, a good drying effect can be achieved, so the water in the cross section of the material to be dried