单螺杆挤出过程固相破碎碎块径向熔融机理研究

STUDY ON THE RADIAL MELTING MECHANISM OF BROKEN SOLID PIECES IN THE PROCESS OF THE SINGLE-SCREW EXTRUSION

首次建立了单螺杆挤出过程固相多点破碎球形块径向熔融模型,并推导出球形块内部温度分布公式。根据固相加速实验结果,提出固相碎块轴向熔融长度计算公式。利用上述公式,对LDPE和PP进行了计算。此外,分析了三种规则几何体与熔融速度关系,指出了细化碎块实现稳定挤出的途径。

The melting model of the broken solid pieces in the later stage of the melting zone in the process of the single-screw extrusion is firstly established, and the equation calculating temperature field of broken solid pieces is mathematically deduced. Combined with the experimental results, the equation is put forward for calculating the melting length of the broken solid pieces. Two materials LDPE and PP had been calculated by using above equations. Also, the relation between shape and melting speed of three regular geometric figures is analyzed as well as the ways to achieve steady extrusion are pointed out.