BOPET生产中传热模型的建立与应用

针对双向拉伸聚酯薄膜(BOPET)的生产特点，建立了一套模型，用于加工过程中的传热问题研究。结果表明，对于BOPET的生产，铸膜时必须保证有充分的冷却时间，铸膜辊的直径大小取决于生产线的上限膜厚；对于特厚膜的生产，需采用双辊冷却的方法，冷却时间比最好为85：15左右；对于纵向拉伸的预热系统，采用多辊双面交替加热的方式为佳；对于横向拉伸的预热系统，膜厚对加热效果影响较小，预热区的选择取决于生产速度。

Establishment and Application of Heat Transmission Model for Production of BOPET

In accordance with the characteristics of the production of BOPET,a model was established to analyse the heat transmission during the processing.The results showed for the production of BOPET,the cooling time for film casting should be long enough,and the diameter of the casting roll depended upon the upper limit of the film thickness of the production line.For the production of the film of supper thickness,twin-roll cooling should be used,and the ratio of cooling time would better to be about 85:15.In the longitudinal orientation preheating system,multi-roll and double-side alternating heating would be the best.In the horizontal orientation preheating system,the thickness of the film had little effect on the heating,and the selection of the preheating zone depended upon the production rate.This model could be applied to the processing of the production of other BOPET of the like.