Electrofusion key to piping network upgrade

Aramco is saving a significant amount of money by using new electrofusion welding technology on approximately 37 kilometers (km) of high-density polyethylene (HDPE) firewater pipes at the Safaniyah gas-oil separation plant (GOSP), according to Aramco’s Oil Facilities Projects Department.

Electrofusion utilizes built-in electric heating elements, a type of prefabricated molded socket fittings called electrofusion couplers, which are used to weld HDPE pipe joints together. The pipes are placed in a fitting, electricity is applied, and the heaters melt the inside and exterior ends of the pipes to form a strong joint. 

As the heating cycle finishes, the pipes are left to cool, and the melted HDPE solidifies to form a joint that is stronger than the original pipe and can withstand various internal and external loads. Previously, Aramco practiced “butt fusing,” in which heat was applied to the ends of the plastic pipes, which were then forced together to make a permanent joint.

The Safaniyah GOSP firewater pipe network upgrade project is the first time the electrofusion welding technique has been used at Aramco, leading to smaller trenches, fewer construction man-hours, significant time savings, and stronger pipe joints compared with butt fusing, with a significant cost savings achieved. 

Over the past two years, electrofusion technology has been shown to have significant advantages over the butt fusion method based on brownfield project experience.

Approximately 37 km of HDPE firewater network pipes will be welded in the GOSP, involving approximately 10,000 electrofusion joints. To date, the project has completed laying 26 km of HDPE pipe, utilizing 5,500 electrofusion joints. Approximately 15 km of completed pipes have been hydrotested successfully, validating the quality of the technique.

— By Fahad A. Alzahrani