Accelerated electrofusion welding of polyethylene pipes employing a novel xylene-based ‎conductive polymer intermediary for optimized pulse application

Document Type : Articles

Authors

• Abdolali Rahimi Mozafari ¹
• masoomeh emadi ²
• Bizhan Honarvar ¹
• Moein Nabipour ¹

¹ Department of Chemical Engineering, Marvdasht Branch, Islamic Azad University, Marvdash

² Department of Chemistry, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran

10.30495/jopn.2025.33842.1332

Abstract

The natural gas is an important energy source that is increasingly being utilized due to its convenience and clean energy provision. Natural gas is safely supplied to consumers through an underground gas pipeline network made of polyethylene materials. In electrofusion, which is one of the joining methods, copper wire is used as the heating wire. However, it takes a long time for the fusion to occur because of the low electrical resistance of copper. Therefore, in this study, electrofusion with the replacement of the copper heating wire with an intermediate material containing an electrically conductive and thermally conductive polymer was performed to reduce the fusion time and improve the production during the connection of large pipes. After the fabrication of the electrofusion joint in the polyethylene pipe using the intermediate material, fusion, thermal and tensile tests were conducted. The results showed that the fusion time is shorter, and the temperature inside the pipe is higher with the increase in the current amount. The optimal welding voltage value was the one in which the melt time was short, and no deformation was observed in the pipe. Therefore, it was demonstrated that the conductive interface can be used to replace the copper heating wire

Keywords

• Electrofusion
• Polyethylene
• Xylene
• Field joint
• TGA-DSC

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