In HDPE piping, which method is commonly used specifically for tees?

• A. Butt fusion for tees
• B. Electro fusion for tees
• C. Mechanical couplings for tees
• D. Threaded joints for tees

Answer: (B)

In HDPE piping, joints are normally made by fusion to create a continuous plastic bond. For adding a branch, the method that is commonly used is electrofusion, because fittings with electrofusion technology have built-in heating elements that melt the pipe and the fitting together uniformly when current is applied. This produces a strong, leak‑proof joint around the branch and is well suited to the socket style of tees.

Butt fusion can join pipe ends, but making a reliable butt fusion with a tee in place is more complex and less practical in the field, since it requires special alignment and tooling for the branch geometry. Mechanical couplings are possible but introduce additional potential leak paths and are generally less durable for HDPE pressure service. Threaded joints aren’t standard for HDPE and typically require adapters, which add complexity and potential failure points.