Potable Water Standpipe and Riser Lining

The challenge

A potable water standpipe and its riser carry treated drinking water, so the inside steel has to stay clean and intact. Over time the wetted steel corrodes, and pitting concentrates at the floor and along the weld seams where water sits and stress is highest. That corrosion does two things at once. It puts rust into the water that has to stay clean, and it thins the wall that holds the column of water. Left alone, the pitting deepens, the seams keep losing metal, and the asset moves toward a release and an outage on a system that cannot simply be shut off.

Our approach

We take the internals back to bare, sound steel before anything else goes on. We grit-blast the wetted surfaces to a clean, profiled finish so the repair and the lining bond to metal, not to old corrosion. We rebuild the pitted floor and the weld seams with a Belzona 1000 Series composite, bringing the lost profile back so the lining has continuous steel to sit on. Then we apply a lining suited for potable water service across the wetted steel, so the rebuilt floor and seams and the surrounding wall all sit under one continuous barrier. The water stays clean and the corrosion is held back, all without cutting and replacing plate.

1. Assess the wetted steelWe inspect the standpipe and riser internals to map the pitting at the floor and weld seams and to confirm the surfaces that need rebuilding and lining.
2. Grit-blast prepWe grit-blast the wetted steel to a clean, profiled surface so both the composite and the potable-water lining bond to bare metal.
3. Rebuild floor and seamsWe rebuild the pitted floor and the weld seams with a Belzona 1000 Series composite, restoring lost profile with no plate replacement.
4. Apply potable water liningWe apply a lining suited for potable water service over the wetted steel so the rebuilt areas and the wall sit under one continuous barrier.
5. Inspect and return to serviceWe check the lining and the rebuilt areas and hand the standpipe and riser back ready for potable water duty.