Non-intermeshing

Bigio D, Wang K. Scale-up rules for mixing in a non-intermeshing twin-screw extruder. Polym Eng Sci 1996 36(23) 2832-2839. 

A. Kaplan and Z. Tadmor, Theoretical Model for Non-Intermeshing Twin Screw Extruders, Polym. Eng. Sci., 14, 58-66 (1974). 

S. Satija and C. S. Tucker, Effect of Screw Root Profile on PMMA Melting in Counterrotating Non-intermeshing Twin Screw Extruder, SPE ANTEC Tech. Papers, 40, 248-255 (1994). 

K. Nguyen and J. Lindt, Finite Element Modeling of a Counterrotating, Non-intermeshing Twin Screw Extruder, Polym. Eng. Sci., 29, 709-714 (1989). 

Fig. 13.1. Different types of extruders, a) single screw b) co-kneader c) non-intermeshing, mixing mode d) nonintermeshing, transport mode e) counter-rotating, closely intermeshing f) co-rotating, closely intermeshing g) conical counter-rotating h) self-wiping, co-rotating.

The twin-screw injection molding extruder is an injection molding machine that is capable of both blending/compounding and extrusion in one step. Because it is a one step process, the fibers never go through the entire extrusion process as well as the pelletization that limits the fiber size, but are blended into the molten plastic before injection. The screw part of this machine is based on a non-intermeshing, counterrotating twin-screw extruder (Chapter 5). One of the screws in this machine is capable of axial movement and has a non-return valve on the end. This action enables the screw to inject and mold parts. 

In the most simplistic view, the counter-rotating non-intermeshing twin-screw extruder could be viewed as two tangential single-screws sitting side by side in a barrel with an open apex area between them, see Fig. 10. Unlike intermeshing twin-screws, the non-intermeshing... 

Since the screws do not intermesh, the nonintermeshing extruder is not subjected to some of the same mechanical tolerance constraints as the other twin-screw extruders. This enables the non-intermeshing machine to be built to an almost unlimited 1/d ratio. A 72 to 1 1/d unit was used for a number of devoli-talization experiments. The enhanced length capability provides a mechanism for the increased internal volume. 

Fig. 11 Crosssection of counter-rotating non-intermeshing extruder. (Courtesy of the Polymer Processing Institute.)...

Foster, R.W. Lindt, J.T. Bubble free devolitaliza-tion in counter-rotating non-intermeshing twin screw extruders. Polym. Engng. Sci. 1990, 30 (7), 424-435. 

CRNI counter-rotating non-intermeshing ZSK Zwei Schnecken Kneter (two-screw... 

In the case of twin screw extruders many designs are available including co-rotating, counter-rotating, intermeshing and non-intermeshing... 

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