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A spray or light painting system to cover the inner surface of a plastic tube

I'm looking for a thin metallic painting system to cover the inner surface of a HDPE pipe of 510 mm OD (15 mm wt). The purpose is to reduce the permeation of Kerosene through the plastic pipe. The Kerosene is not flowing, but static and frozen in a gel form. So, an aluminum spray providing a 20 to 30 µm of metallic layer will stop the permeation. What should be the surface preparation onto the PE tube to get the Aluminum paint well bonded before kerosene gel injection. Any idea of the cost per m2 ? Type of product ? Surface to cover = 6km of HPE Pipe (510 mm OD 15mm wt)

Regards,

PIONETTI
SAIBOS Services SA - France
2003

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2003

Hi Pionetti,

Re any type of 'internal' painting, you'd have a helluva job to make any paint adhere. On top of that all Polyethylenes have a very high coeffic. of thermal expansion and are very, pipe-wise speaking, flexible ... so you'd face delamination, I think, in no time.

Why even consider hdPE for Kerosene? The corrosion charts do NOT recommend it. Some say it should not be used even for its big sister, PP. However, molecular activity at those low temperatures would be very little.

Sorry, but you are 'barking up the wrong tree' and you will definitely encounter failure and permeation. Even if, if, if a miracle paint existed, when it came to the l0 M joints, just HOW would you ensure that the paint coating would exist because internally a fusion joint will cause a slight swelling.

But at a last tactic, I'd try HOECHST Chemical to see if they have a h.d. Pe resin that can be heat fused. Maybe they might have a fuseable uhmw resin.

Bonne Chance ... you'll need it !

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).