How should PE pipes with different wall thicknesses be connected?

If butt fusion must be used, special preparation is required. The thicker pipe should be machined or turned down so that its end wall thickness matches that of the thinner pipe. Only after this adjustment can a proper butt fusion joint be made. Without this step, the uneven melting behavior of the two walls may cause misalignment, incomplete fusion, or internal stress, which could later lead to cracking or joint failure during service.

In short, electrofusion is the safer and more reliable option when joining pipes with different wall thicknesses — while butt fusion is possible only with precise preparation and skilled operation.