Story #01 · Brownfield

The pipe that wasn’t on any drawing

BrownfieldAs-built

It was a straightforward revamp. A new 6” process line, forty metres through a congested pipe alley in a refinery running since the 1970s. I had the as-built drawings, the 3D model, three days of modelling behind me, and a routing that cleared everything by at least 150mm.

Then I went to site.

Halfway down the corridor, at exactly the elevation I had chosen, ran a 4” utility pipe. No line number. Not on any drawing. Not in the model. Just quietly sitting there, carrying something, going somewhere.

What I found out later

Installed during a turnaround in the late 1990s as a “temporary” measure. Never documented. Still in service twenty-five years later, feeding a heat exchanger that didn’t appear on the current P&ID either.

I rerouted. A day and a half of modelling, a revised isometric, and an uncomfortable conversation with the project manager. The site visit had taken twenty minutes.

The lesson isn’t that as-built drawings are wrong — every experienced designer knows that. The lesson is that knowing they’re wrong isn’t enough. You have to act on it, every single time. Ten minutes of field verification at the start would have saved two days.

All stories Story #02 →