DESAIN MODIFIKASI SCREW EXTRUDER UNTUK MENINGKATKAN OUTFLOW YANG OPTIMAL DAN MENINIMALKAN CACAT PRODUK PADA PLASTIK

Abstract

Screw is the main component of a plastic extrusion machine. which functions as a driving shaft, cutter, and hot plastic stirrer contained in the barrel, the problem that is often experienced by the Plastic industry so far is the number of rejecks (reject products / defective products). From the results of the study it is known that the cause of the product failure problem is the lack of input material into the mold, and the need for design changes in the screw, because the screw is the heart of the extruder machine.Modifications made on Screw include (design of mixer, barrier fin, Channel depth, and Helix angle) with the aim that the output (outflow) increases, especially on machines that already have a long service life that often experience product defects with average defects that are holes , tear and product dimensions are not the same / deviate. Screw the results of this modification have been tested in the factory using ABS and Polypropylene type plastic material, and an achievement was obtained that on a conventional screw with 60 rpm rotation the outflow (output) was 151x with a maximum pressure of 239.1MPa, and

Viscosity 98 Pa.s, And when the rotation is raised to 120 rpm the outflow is 302x with a maximum pressure of 478.2 MPa, and Viscosity 98 Pa.s, For screw modification with 60 rpm rotation, the outflow is 190.79 with a maximum pressure of 187.03 MPa, and Viscosity

98 Pa.s, And when the 120 rpm rotation with screw modification is obtained an outflow (output) of 380x with a maximum pressure of 374.06 MPa, and Viscosity of 98 Pa.s.From the results of the observations it was found that a very significant comparison between the two test samples, namely, using screw modification produced an outflow of about 27% greater when compared to using a conventional screw in the same round.