The Project
NZ MechTech was engaged by Corde to replace the existing 450mm and 350mm underground aeration pipework at the Pines Wastewater Treatment Plant. All of the old pipework was replaced with Schedule 10 stainless steel pipe.
The Challenge
The pipework was buried, so it was only uncovered once work started on site. That meant full measurements couldn’t be taken before fabrication began. On top of that, the aeration system could only be shut down for 3.5 hours at a time. Every changeover had to be finished and the system back online inside that window.
What We Did
We worked through the replacement one section at a time. As each section went in, our team measured the next one and fabricated it in the workshop. We aimed to keep fabrication two days ahead of installation. Flange adaptors joined the new stainless pipework to the existing pipework, so the system could go back on within each shutdown. Before every shutdown, we briefed everyone involved on which sections were being changed and in what order.
The Result
Every section of pipe was replaced inside the shutdown windows we were given. The plant kept running throughout, and the aeration system now has new stainless steel pipework.
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