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The oscillating die: A useful concept in polymer extrusion
Author(s) -
Casulli J.,
Clermont J. R.,
Von Ziegler A.,
Mena B.
Publication year - 1990
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.760302310
Subject(s) - die swell , extrusion , materials science , die (integrated circuit) , amplitude , plastics extrusion , pressure drop , polystyrene , transverse plane , vibration , composite material , swell , polymer , mechanics , acoustics , optics , thermodynamics , structural engineering , physics , nanotechnology , engineering
The effect of superimposing longitudinal and transverse oscillations on the die section at the exit of an extruder is examined. Longitudinal oscillations ranged from 0 to 30 mm in amplitude, and frequencies varied between 0 and 50 Hz. Transverse vibrations varied from 0 to 0.35 rad in amplitude and from 0 to 50 Hz in frequency. Experiments were performed in two types of extruders: a horizontal Brabender Plasticorder and a vertical Scamia both with similar characteristics of 7 Kw power output and 7.10 5 Pa maximum pressure. The polymers used were high and low density polyethylene and polystyrene. The overall effect of the oscillations is to increase the mechanical properties of the extrudate as well as to reduce the pressure drop in the die section. This pressure reduction results in a considerable saving of the total power consumption per unit weight of extrudate. Within a given range of amplitude‐frequency of oscillations, overall power savings of up to 25% are possible with respect to the stationary mode. Furthermore, the total flow rate through the die is enhanced by the vibrations and the die swell is diminished.