Design of a Mini Injection Molding Machine and Injection Analysis of Products Using CAE Software

Nurul Dwi Rahma; Aidil Zamri; Mulyadi Mulyadi; Yuliarman Yuliarman

Authors

Nurul Dwi Rahma Department of Mechanical Engineering, Politeknik Negeri Padang, Indonesia Author
Aidil Zamri Department of Mechanical Engineering, Politeknik Negeri Padang, Indonesia Author
Mulyadi Mulyadi Department of Mechanical Engineering, Politeknik Negeri Padang, Indonesia Author
Yuliarman Yuliarman Department of Mechanical Engineering, Politeknik Negeri Padang, Indonesia Author

Keywords:

Injection molding, recycled HDPE, CAE, ball screw, weldline

Abstract

The increasing amount of HDPE (High-Density Polyethylene) plastic waste requires more efficient and economical processing technologies, particularly for small-and medium-scale applications. This study aims to design a mini injection molding machine for processing HDPE plastic waste and to analyze the product injection process using Computer-Aided Engineering (CAE)-based software. The machine was designed using SolidWorks, focusing on the injection system, clamping system, and heating system. The injection process was analyzed using SolidWorks Plastics with variations in gate position and melt temperature to evaluate injection pressure, material flow distribution, and product defects. The results show that the designed machine is capable of producing a stable HDPE injection process using a screw with an L/D ratio of 20:1 and a ball screw-based clamping system. Simulation results indicate that a gate position located at the center of the product provides the best flow distribution with minimal weldline defects. The optimum melt temperature was found to be 240°C, with an injection pressure of approximately 10 MPa. These findings indicate that the integration of mini injection molding technology and CAE-based analysis has the potential to support more efficient plastic recycling processes while minimizing design revisions, material waste, and manufacturing costs in small-scale production systems

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