ABSTRACT

The selection of the proper screw for a given processing envirorunent should be based on the resin or resins to be processed [5]. Chapter 2 noted that the two broad groups of pJastic, crystalline and amorphous, do not meh in the same manner nor do they conduct heat in the same way. The degree of sensitivity to shear also varies significantly between the two material types. Without getting too deeply involved in screw design technology, it is important to understand some fundamental differences in materials and how those differences influence screw design.