FRP Compatibility with chemically treated water
FRP Compatibility with chemically treated water
(OP)
I have corrosion issues with currently installed galvanized steel components (railing, beams, etc.). I am trying to figure out the best material to replace the existing items with. I am pretty set on FRP, but am not sure if there may be a better material for the application. Any insight is appreciated. I have attached a photo of the corrosion (after 5 years in service) and some water analysis for review.







RE: FRP Compatibility with chemically treated water
Applying an epoxy coating to protect the galvanized steel locally may be an option too.
RE: FRP Compatibility with chemically treated water
RE: FRP Compatibility with chemically treated water
Was heavy Zn application used?
I suspect that the answer to both is NO.
Going to FRP should work well.
But so would properly made, galvanized, and sealed metal parts.
FPR is not nearly as stiff as metal, so dimensions will need to be much larger or everything will feel 'bouncy and flexible' even if it can carry the loads.
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P.E. Metallurgy, Plymouth Tube
RE: FRP Compatibility with chemically treated water
I believe part of the issue is the chemicals we inject into the water (Sodium Hypochlorite, Sodium Bromide, Sulfuric Acid, etc). This gets on the metal with the spray and eats it up.
RE: FRP Compatibility with chemically treated water
But wet/dry cycling or near the interface is aggressive even with good water.
I presume that you are controlling to a 'scale index' target of some sort.
And adding some inhibitors and biocides. Fairly standard stuff.
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P.E. Metallurgy, Plymouth Tube
RE: FRP Compatibility with chemically treated water
It could be a safety issue as the staffs walk on the slippery walkway and contact with the water with unwanted chemicals.
RE: FRP Compatibility with chemically treated water
RE: FRP Compatibility with chemically treated water
RE: FRP Compatibility with chemically treated water