Effect of Welding Shoe Design on Weld Strength in High-density Polyethyleneextrusion Welding

As international environmental regulations become increasingly stringent, research into eco-friendly alternatives to fiber-reinforced plastic (FRP) has intensified in the shipbuilding industry. High-density polyethylene (HDPE) has emerged as a promising alternative, offering excellent mechanical properties, recyclability, and cost benefits compared to FRP. This study evaluates the influence of welding shoe design—Butt shoe, Round shoe, and Round shoe with an additional press tool—on weld quality and mechanical strength in HDPE extrusion welding. The Butt shoe produced optimal bead geometry with minimal defects, whereas the Round shoe resulted in excessive bead height and various weld defects. Incorporating a press tool slightly improved weld compactness but was less effective than the Butt shoe. The findings highlight the importance of selecting appropriate welding shoes to ensure structural integrity and compliance with industry standards in HDPE shipbuilding.