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Pipeline external algae formation

Pipeline external algae formation

Pipeline external algae formation


Working for a gas plant and our Inspection Team has been reporting in some piping systems an external condition described as "Mild external biological/algae formation on piping" (refer to attached file). Piping is Carbon Steal and externally coated. I am seeking your advice and guidance regarding the following:
1.) Could the condition exacerbate any potential external damage mechanism?.
2.) Could the actual condition be accepted?
3. What could the situations where an action is required like removing algae layer?

My general thought is that as long as the external coating is in good shape condition will not drive short/mid term actions but I am afraid that I could be missing something.

Thanks in advance for your support, looking forward for your comments.


RE: Pipeline external algae formation

Just looks shite.

These must be slightly colder than atmospheric and get damp / condensation on them? Or be permanently in the shade?

They might mask something underneath with the paint, but think you would spot that.

The cost of getting to them is probably a bit high but could you use a cherry picker and a long pressure washer lance to wash it all off?

Some pretty meaty flanges there! Class 2500?

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RE: Pipeline external algae formation

Hi LittleInch,

Thank you very much for you feedback. You are righ, pipe system temperature slightly below atmospheric temperature and it gets damp. As you mentioned washing off could be an option but I was wondering if there is an stronger way to technically justify the corrective action rather that just based on the fact that it looks shity. You were also right with the flange rating...

Miguel Diaz.

RE: Pipeline external algae formation

Mad 1974,

The only thing I can see is that it could mask deterioration of the coating. otherwise I think that sort of algae is pretty benign.

You should be able to get some anti algal paint or wash to avoid having to do it frequently, but I think it's just a visual thing.


Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Pipeline external algae formation

I agree, my only worry is that he algae will be 'eating' your coating.
So this coating had no gloss to start with, correct?
It might be worth looking at the cost of cleaning and top coating.
This is a big issue with water towers also.
They have some great coating systems to help fight it.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Pipeline external algae formation

That's growth normal in a humid climate. If you want to control it or clean it, a bleach solution and pressure washer every 1-2 years will oxidize and remove it.

RE: Pipeline external algae formation

If algae layer is destructing painting layer, corrosion shall be of concern, periodic sandblast and paint touch up wold be recommended.

RE: Pipeline external algae formation

If you will decide fighting algae note the genesis - metal is below air dew point. You should eliminate dew point or provide moisture barrier otherwise algae will come back soon.

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