Eventos Anais de eventos
COBEF 2017
Congresso Brasileiro de Engenharia de Fabricação
ON THE DESIGN AND TECHNOLOGY OF CO-ROTATING TWIN SCREW EXTRUDERS
Submission Author:
Zilda de Castro Silveira , SP , Brazil
Co-Authors:
Joaquim Manoel Justino Netto
Presenter: Joaquim Manoel Justino Netto
doi://10.26678/ABCM.COBEF2017.COF2017-0017
Abstract
This document presents a systematic design approach for co-rotating twin screw extruder components, elaborated from concepts on Twin Screw Extrusion (TSE) technology and from the experience acquired by the authors in designing a mini twin screw extruder for future application as an interchangeable printing head in Additive Manufacturing (AM). Twin screw extrusion is commonly used in polymer compounding due to its good mixing performance, self-cleaning property and process flexibility. Few works have been produced in Brazil on the design of twin screw extruders, especially dealing with the screw geometry, whose elements are responsible for providing the different flows that favour material mixing and conveying inside the extruder. In addition to the complex geometry, the flexibility provided by modular elements that configure the screws makes it difficult to establish design guidelines on the subject, preventing also the development of a comprehensive software capable to inform the best screw configuration to a certain process. However, undertaking rigorously the procedure proposed to determine the geometry of the screw elements makes it possible to ensure the desired self-wiping property along with constant clearance in the intermeshing region between the screws as well as to determine some operational parameters that provide relevant information about the process. As recommended by the procedure, a mock-up of the resulting geometry was generated in order to verify the functionalities of the embodiment design. Results show that the screws can rotate without interference and the material is conveyed as expected towards the die.
Keywords
polymer processing, twin screw extruder design, additive manufactruing
