# Optimization of Injection Molding Processing Parameters for Thin-Walled Plastic Parts Manufactured for the Automotive Industry

## TL;DR

This paper studies how to optimize injection molding for thin-walled plastic parts used in the automotive industry to reduce defects and improve sustainability.

## Contribution

The study provides a correlation between theoretical and experimental results for flow length and weight in thin-walled injection molding.

## Key findings

- Thinner walls (0.50 and 1.50 mm) could not be filled at maximum pressure due to temperature drop at the flow front.
- Walls of 2.70 and 3.00 mm could be filled successfully with a 90% agreement between theoretical and experimental results.
- Higher pressure increases the deviation between theoretical predictions and experimental outcomes.

## Abstract

The fabrication of thin-walled plastic parts has potential in the automotive industry in terms of sustainability and circular economy targets to decrease any harmful effects on the ecosystems, cost and performance. Injection molding of thin-walled automotive parts is more complex in terms of processing defects compared to traditional plastic parts. Optimization of processing parameters is of critical importance to solving problems and defects in the production of thin-walled parts. In this study, the flow length and weight of thin-walled spiral parts (with wall thicknesses of 0.50, 1.50, 2.70 and 3.00 mm) were investigated with theoretical and experimental studies. The theoretical flow length and weight of the thin-walled spiral parts were determined by Moldflow analysis according to the pressure and wall thickness. The correlation graph between theoretical results and experimental measurements was obtained. When the wall thickness of the thin-walled spiral parts increased, the flow length of the thin-walled spiral parts increased. As a result, it was found that the thin-walled spiral part mold could not be filled for wall thicknesses of 0.50 and 1.50 mm at maximum pressure due to decreasing temperature at the flow front. In addition, the thin-walled spiral part mold can be filled for a wall thickness of 2.70 and 3.00 mm. In the correlation study conducted for these values, an agreement of approximately 90% was achieved. However, it was also observed that as the pressure increases, the deviation between the experimental and theoretical results becomes more pronounced.