常规热压法干法纤维板热压传热的研究——Ⅰ理想条件下板坯中心层达到胶粘剂固化温度所需时间的数学模型

Theoretical Study of Hot Pressing Time of Wood Based Panels

推导了理想条件下板坯中心层达到胶粘剂固化温度所需时间的数学模型 ,并得到了如下 3点结论 :1该时间与板坯的导温系数成反比 ,与板厚的平方成正比 ;2该时间随热压板温度与要求的板坯中心层温度之差值的增大而减小 ;3该时间的长短随胶粘剂不同而不同 .

By ratiocinating the theoretical formations of the pressing time of wood based panels and analyzing all the factors that affect the pressing time, four conclusion points are given below: 1. The pressing time is in inverse proportion to thermal diffusivity, and in direct proportion to the square of the thickness of panels. 2. The pressing time has little relation to the species and density of wood, but is greatly affected by the moisture content of the panels; with the moisture content increasing, the time needed to heat up the panels prolongs. 3.To cut the pressing time, the method of increasing the temperature of pressing is more effective than that of increasing the initial temperature of the panels. 4. With the difference between the temperature of the pressed panels and the required central temperature of them becoming bigger, the pressing time is shortened; when the difference is small, the influence is great and while the difference is great, the influence is mild. 5. Different adhesives need different pressing times.