Black residue

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eagleray2003

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I just got a call from my LDS and they are telling me I have a heavy black residue in my tanks, any suggestions what caused this and what the fix is to repair this, shop wasn't sure yet what it was.
 
If a compressor filter degrades to the point that it allows activated charcoal to blow past into the fill system it can show up as black residue inside the tank and valve...

This breakdown is most often caused by moisture intrusion into the filter.

Just one possible suggestion...

Jeff Lane
 
Some of the newer tanks have a black looking coating inside them.
 
Sounds like you got some stuff coming in from the compressor. If the shop that is VIPing your tanks the same as the ones that fill, then they need to check their compressor.

Eric
 
GTADiver once bubbled...
Some of the newer tanks have a black looking coating inside them.

Care to elaborate on which cylinders have this type of lining?

Thanks,

c_c
 
I believe GTAdiver is refering to alrock:

alrock has a dull black appearance, used as a corrosion preventative on some aluminum cylinders.


Jeff
 
1) It says it is oxygen clean but it isn't (or wasn't). Most people are expecting a "big bang" when you put Oxygen in a "dirty tank". Nope, mostly just black soot or goo.

2) Malfunctioning compressor.

3) Some bogus coating... but ALL of the coatings I have seen have been "flakey" and not "heavy".

However, without seeing it, it is hard to pin point.
 
CC, all Faber (Italy) tanks are internally coated with black phosphate. The coating has a flat or rough textured appearance. I've never seen a tank with visible charcoal inside but it could happen if the particle pads in the final filter were omitted during assembly. If the wrong foam pad was used as a cheap replacement for a polyester pad, samo, samo. It could blow through. The crud could be easily washed out, though.
 
pescador775 once bubbled...
CC, all Faber (Italy) tanks are internally coated with black phosphate. The coating has a flat or rough textured appearance.

As far as I know the production cycle of Faber cylinders does not include any kind of coating the interior of the cylinder after it is shotblasted.

AFAIK--The mechanism of all phosphate coatings takes place in an acid bath that contains the coating chemicals. The chemicals react with the metal to be coated, and at the interface, a thin film of the solution is neutralized by reaction with the metal. When this solution becomes neutralized at the interface, the solubility of the metal phosphate is reduced and a precipitate is formed as a crystal. These crystals are attracted to the surface of the metal by the normal electrostatic potential within the metal.

I am interested in getting this information to add to/adjust cylinder inspection information if necessary.

Thanks,

C_C
 
https://www.shearwater.com/products/peregrine/

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