On Mon, 11 Mar 2019 10:37:31 -0700 (PDT)
misterroy wrote:

What could have caused the heating pipe to corrode so badly that it
failed? It was next to an external wall and lagged. The are a couple
of lengths of the pipe lying outside the building unused for the same
6 years, other than the threaded ends, they look new. image
https://drive.google.com/open?id=1o8...cqBdRGYatmQb6R

Accumulation of moisture inside the lagging plus warmth from lagging
equals accelerated oxidation?