Aluminum Dome roofs

[mustafa2014]

Dear all, good day

we have here in our gas plant a damaged steel roof for condensate storage (light product). since we need the tank back in service we go to aluminum dome roofs with (internal aluminum floating roof). our tank is by the sea (just 200m), My question is:

1- is the aluminum roof corroded in short time.
2- is a good practice to use this type of roofs since it is accepted by API 650 / 653?

please ADVICE URGENTLY

 

[IRstuff]

"1- is the aluminum roof corroded in short time."

Is short time a nanosecond, a day, a year?

TTFN
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[mustafa2014]

dear IRtuff,
Many thanks.
I mean for how long could be used before we have to changed ?

 

[MikeHalloran]

The sea is not kind to either steel or aluminum.

It might be possible to find some tabular corrosion rate data collected in a laboratory under precisely controlled conditions, and to use that to extrapolate a useful life for the roof. ... but it would be largely a waste of time, because the roof is not in a laboratory.

You will have a better idea of the roof's life expectancy when the new one fails to perform adequately. That will guide your purchase of its successor.

The only other useful data you may have is the historical failure rate for adjacent/nearby tanks of similar construction bearing similar product.

There may also be valuable anecdotal data in the minds of whatever 'old timers' you have working there, or hanging out here, so there's good reason to ask the question, but there is not good reason to delay purchase of _something_ to serve as a tank roof.

You clearly understand that last point, given your request for ADVICE URGENTLY. My advice is that _anything_ you do has a 50 pct chance of improving your situation, whereas failing to do anything has a 100 pct chance of turning out badly. So toss a coin.






Mike Halloran
Pembroke Pines, FL, USA

 

[IRstuff]

"I mean for how long could be used before we have to changed ?"

For what criteria? Aesthetics, pits, holes? What does the roof need to do until it's "changed"

TTFN
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[boo1]

AL roofs work if the correct alloy, installation, and isolation are used. Look at what is common in your area.

 

[tbuelna]

What is the reason an aluminum roof is more readily available than a steel replacement?

The aluminum roof will definitely cost more. But as long as the steel or aluminum roof is properly maintained, either one should provide acceptable service life. Of course, aluminum compatible primers usually cost more than those for steel.