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Moisture Level - Carbon Steel

Moisture Level - Carbon Steel

Moisture Level - Carbon Steel

(OP)

Hi all,

I would like to seek for opinions on the below situation:-

With >80ppmV moisture level, will it cause any corrosion issue to the flowline designed from carbon steel material?


Thanks and Regards

RE: Moisture Level - Carbon Steel

Carbon steel is always subject to corrosion: From both inside and outside. Inside erosion is more severe than simple corrosion if the water vapor is "wet" and at high speed. Static (standing water) leads to corrosion if O2 is present in water or vapor.

Your question can't specifically be answered with what you've said.

RE: Moisture Level - Carbon Steel

Pure water alone cannot cause corrosion - it is all the stuff that comes together with the water vapor that causes corrosion - the phase conditions also matter - whether the moisture can condense at some other conditions etc.

Gremlins to watch out for, when water vapor is present are dissolved O2, CO2, H2S, dissolved chlorides, ammonia, amines - the list goes on..



RE: Moisture Level - Carbon Steel

"Pure water alone cannot cause corrosion"

That is not entirely the case. Demineralized water, distilled water, and even good old potable water can all be corrosive to common piping materials without anything special going on.

RE: Moisture Level - Carbon Steel

I wouldn't worry about it, except for how you will ensure that you can keep water content down to 80ppm in a flowline? Are you sure it is a flowline? Coming from a well and going to a process plant, right?


RE: Moisture Level - Carbon Steel

GameJudge

All the flavours of water you've mentioned have at least dissolved O2 in it.

Was referring to PURE water

And one more contaminant in water : living microbes cause MIC - microbial induced corrosion, and they enable metabolism with any of CO2, O2, H2S or hydrocarbons in the presence of water.

RE: Moisture Level - Carbon Steel

George,

Are you really saying that the oxygen in "Pure" water would be nonreactove when in contact with iron in steel and thus, a corrosion reaction will not form?

RE: Moisture Level - Carbon Steel

By pure water, I meant water with zero dissolved gases in it, which includes O2.

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