| 摘要 |
This invention of Heated Die Lips System is specifically designed for use in Film Extrusion Dies. Use of such a system allows Film Extruders to be run at high er production rates with narrower die gaps, while eliminating the melt fracture properties. This Heated Die Lips System, is installed in the final die land area of the extrusion die, on each side of the die gap. It applies direct heat to the polymer melt as it exits the die lips, and reduces the melt viscosity. Thus the 'Critical shear stress' value of the melt is reduced. This results in postponement of the melt fracture property of the film and higher production rates are achieved without melt fracture. Furthermore, this system has been designed so as to insulate it from the mai n block of the die, minimizing heat dissipation and providing an enclosed system for uniform heating of the die lips. |
