Design and fabrication of an automated complete deflashing machine for HDPE plastic bottles

Abstract

During HDPE bottle production via extrusion blow molding (EBM), flash typically forms at the bottle bottom, neck, and mold parting lines. Removing this flash is essential for dimensional accuracy, surface quality, and product functionality. However, in many production lines, this operation remains manual or semi-automated, resulting in low throughput and inconsistent quality. This study presents the design and fabrication of an automated deflashing machine for HDPE bottles that integrates clamping, positioning, and rotary cutting mechanisms to remove flash at both the bottle bottom and neck within a single compact system. The machine employs rack-and-pinion-driven assemblies with pneumatic actuation, allowing flexible adaptation to various bottle sizes and wall thicknesses. Experimental results demonstrate stable operation at approximately 700 bottles per hour for bottles with a diameter of 60 mm, height of 70 mm, and wall thickness of 0.4 mm, confirming the system's strong viability for practical deployment in industrial EBM production lines.