Ensure durable electrofusion pipe joints

Ensure durable electrofusion pipe joints – the right tool for the right joint

Electrofusion is a reliable method for joining polyethylene (PE) pipes in the water and infrastructure sector. However, to achieve a long service life – up to 50 years or more – every step of the process must be carried out correctly.

Below is a summary of key factors and recommendations for electrofusion welding. The information is based on a report produced by Hy Ram Engineering, drawing on internal field studies and industry standards such as WIS 4-32-08 (June 2016) and CAD/PM/MSL/1 v1.3 (January 2021).

• Insufficient clamping and/or lack of use of re-rounding tools
• Insufficient scraping
• Contamination of the pipe or electrofusion coupler
• Other

Data source: compiled by Hy-Ram Engineering based on internal field studies and industry standards (including WIS 4-32-08, June 2016, and CAD/PM/MSL/1 v1.3, Jan 2021).

Minimising risk requires the right training and tools – from clamping tools to cleaning wipes

Re-rounding tools – when shape matters

Ovality in pipes is common, particularly in coils or pipes with a high SDR value (thin walls). It is essential that the pipe is round for the coupler to fit correctly.

• Re-rounding is carried out before insertion into the coupler.
• The tools are designed for specific sizes

Scraping – the key to a good weld

The surface of PE pipes oxidises on exposure to air, which impairs weldability. Scraping off the outer layer is therefore essential.

• Mechanical rotary scrapers provide even, controlled removal of the surface, unlike manual scraping.
• They ensure that the correct amount of material is removed – not too much, not too little.
• For branch connections, scraping tools are available that adapt to the shape and size.

Tip: Pipes must never be sanded – this damages the material and creates a risk of weld defects.

Cleaning 

After scraping, the surface must be completely free from grease, dust and other particles.

• Cleaning wipes ensure a clean joint.
• Always wipe the surface with a new wipe – never reuse the same one on multiple welds.

Clamping tools – stability throughout the weld cycle

"The pipe must be held completely still during both welding and cooling. Even small movements can cause cracking in the weld joint."

Clamping tools help hold the coupler and pipe in the perfect position.

• Hydraulic tools are available for larger sizes or more demanding jobs.
• Combined clamping and re-rounding tools make the process both faster and safer.