Air compressor tank treatment
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 40
  1. #1
    Join Date
    Mar 2001
    Location
    New Haven, CT
    Posts
    3,507
    Post Thanks / Like
    Likes (Given)
    44
    Likes (Received)
    680

    Post

    Does anyone know if there is some sort of treatment for aircompressor tanks and rust. Is there any expoxy paint/plastic that one can pour into the tank and slosh around to prevent rusting.

    Thanks,

    Adam

  2. #2
    Join Date
    Jul 2001
    Country
    UNITED STATES
    State/Province
    North Carolina
    Posts
    1,970
    Post Thanks / Like
    Likes (Given)
    178
    Likes (Received)
    406

    Post

    I always thought sloshing with phospheric acid was a good idea to passivate the rust, but I dunno. --Doozer

  3. #3
    Join Date
    Feb 2001
    Location
    Redwood City, CA USA
    Posts
    4,991
    Post Thanks / Like
    Likes (Given)
    184
    Likes (Received)
    918

    Post

    I'd be extremely cautious. You could very easily make the situation worse, corrosion-wise. Any small pinholes in your coating could lead to localized pitting, disastrously weakening the tank wall. Also, you could get crevice corrosion going beneath the coating. An occluded area like the bottom of a pit or end of a crevice can act as a little galvanic cell and eat metal at a frightening rate.

  4. #4
    Join Date
    Jun 2005
    Location
    Pittsburgh, PA
    Posts
    246
    Post Thanks / Like
    Likes (Given)
    10
    Likes (Received)
    5

    Post

    If there's no structural damage, I think POR-15 would be the ideal solution. I haven't tried it, and I'm not recommending it, but it does magical things with rusty metal.

  5. #5
    Join Date
    Feb 2005
    Location
    Castle Hayne, NC 28429
    Posts
    114
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1

    Post

    I have to ask. Why do you care if the inside of your tank is rusty? Pressure vessels are designed with a rust factor figured in.

    I wonder if anyone on here has ever had a tank fail due to rust.

  6. #6
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,653
    Post Thanks / Like
    Likes (Given)
    30
    Likes (Received)
    1225

    Post

    only once
    a small rust pin hole
    but it was someones home (cheap) crap amd probly sat for 2 years full of water

  7. #7
    Join Date
    Feb 2005
    Location
    Castle Hayne, NC 28429
    Posts
    114
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1

    Post

    a small rust pin hole
    And even then, did it create a dangerous situation or did it just leak?

    I am not recommending being unsafe with compressed air. I am just saying that all the necessary safety is already built into the tank. Appling a coating to the inside of the tank will not offer any additional measure of safety. And I only assume that safety is the reason one would consider such a thing, as being the inside of the tank it would not be for appearance.

  8. #8
    Join Date
    Aug 2003
    Location
    Post Rock country, Lacrosse Ks
    Posts
    936
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    3

    Post

    Peckham4,
    If you where in a high humidity location your going to get water in you tank everytime you fill it. I can see where having a tank that has a rust proof lining would be nice. I'd hate to have to buy new a tank every 3 or 4 years. Yes I have had a tank rust out on me, scared the you know what out of me when it let go! Got to looking and it had places all over the botom of the tank where it'd started rusting. I've also seen a few other tanks that have the same problem. This has got me to thinking about using some gas tank sealer to rust proof a compressor tank. Hmmmm!

    Thanks
    Richard

  9. #9
    Join Date
    Apr 2003
    Location
    Berkeley Springs, WV, USA
    Posts
    4,291
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    102

    Post

    In industry air compressor tanks are periodically inspected. They are usually OK but some are condemned.

    How do I know this?

    The air compressor guy was just down the street from my old shop. He would give you a nice tank if you promised that you would be making a barbeque out of it. BTW, he had to know you.

    If you have any doubts about a tank then have an air compressor guy look at it. Once in a while those things do let go.

    Rust isn't the only problem, sometimes tanks get cracks in them due to vibration.

  10. #10
    Join Date
    Nov 2005
    Location
    Port Washington, WI
    Posts
    175
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1

    Post

    This is probably a stupid question but why not make a stainless or aluminum tank?

    If you machined a tank from a billet of aluminum
    it would be way too much $$$

    but could one be cast? Or formed from sheet?
    There has got to be a simple reason for this I just don't get

  11. #11
    Join Date
    Feb 2005
    Location
    Birmingham, AL
    Posts
    4,026
    Post Thanks / Like
    Likes (Given)
    13
    Likes (Received)
    49

    Post

    Why not make your own tank? Because it should be ASME certified for starters. You could hydrostatically test your tank for safety. I think we discussed that here before. Im sure tanks can be quite dangerous and explode with a instant critical failure but I have never seen it happen.

  12. #12
    Join Date
    Jul 2004
    Location
    Reddington, N.J., U.S.A.
    Posts
    3,258
    Post Thanks / Like
    Likes (Given)
    112
    Likes (Received)
    257

    Post

    Why couldn't the tank have a rubber or EPDM bladder installed inside when new? Or maybe cleaned and then coated inside before any rust forms from use?

  13. #13
    Join Date
    May 2003
    Location
    Weirsdale, FL
    Posts
    1,777
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    172

    Post

    You can't win! Last year I bought a new IR air compressor (5 HP, 80 gallon tank). There was some residual pressure in the tank before I powered it up, so I opened the drain. Low and behold, the manufacturer shipped the thing with rusty water already in it!

  14. #14
    Join Date
    Mar 2005
    Location
    Derbyshire, England
    Posts
    37
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Post

    Why couldn't the tank have a rubber or EPDM bladder installed inside when new? Or maybe cleaned and then coated inside before any rust forms from use?
    Basically it's a matter of cost. Small air receivers are made in large numbers at very low prices, and adding an inside coating would add significantly to the costs. You can get internal coatings (e.g. glass) for special applications but they cost more than the tank for small sizes. A less than perfect coating is worse than useless, and cleaning the tank to get a good adhesion, and inspecting it to ensure the coating is good, are expensive processes - it's not just a case of filling it with paint and sloshing it about a bit. Galvanising works, and is cost effective on medium sized tanks (I have 150l galvanised tank) but don't try galvanising a tank unless you know what effect the heating will have on the vessel materials.

    Vessels can be made from alu or stainless, but the welding processes are generally more complex and expensive, in addition to the extra base cost of the material. The US and EU codes effectively do not permit vessels to be made from cast materials.

    As already stated, the design codes all allow for significant corrosion, and tanks will usually last for many years so long as they are regularly drained.

    As for making your own tanks, if you have access to the gear to do the necessary metal forming, you're likely already in the pressure vessel business and will know what's involved. If you don't have the gear to provide the necessary curves then forget it. There aren't any safe shortcuts which can be done with HSM style equipment.

  15. #15
    Join Date
    May 2005
    Location
    JAPAN
    Posts
    1,225
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    10

    Post

    A slight cover on rust completely covering the inside of the tank is better than no rust or spots of clean surfaces.
    The rust acts a barrier inhibiting more rust growth, if you clean the tank you will introduce oxygen to the clean metal and a rust hole will start to form. This protective layer of rust is call a magnetite layer

  16. #16
    Join Date
    Aug 2004
    Location
    USA, Midwest
    Posts
    612
    Post Thanks / Like
    Likes (Given)
    1
    Likes (Received)
    46

    Post

    McMaster Carr offers air tanks in steel, epoxy lined steel, galvanized steel, aluminum, and stainless steel.

    One thing to consider is that if you painted the inside of your tank, make sure you do a complete job. Any defect in the paint would be like a magnet for the free electrons present in the base metal. This would actually cause the tank to rust faster but in a concentrated area at the paint defect.

  17. #17
    Join Date
    Dec 2003
    Location
    suburbs of Ann Arbor, MI, USA
    Posts
    13,038
    Post Thanks / Like
    Likes (Given)
    423
    Likes (Received)
    1015

    Post

    The reason for the low carbon steel tanks is in a single word: ductility

    The ASME guidelines generally have to do with staying out of the arena of fast-fracture...where the tank would appear to go off like a bomb, wrap around a tree, etc.

    There have been terrible disasters earlier in the century involving propane tanks of all things, and the ASME guidelines are designed to prevent those kinds of failures and default to a leaking tank which can be detected, drained, and fixed or replaced without a disaster.

    I won't get into the specifics because I forgot them ( ) but the idea is that the ductility allows an overstressed tank to develop a leak- small crack at a spot. The ductility keeps the crack from propagating at the speed of sound (that I didn't forget) into a wide-open clamshell. The energy that took minutes of large amp draw to build up is then released in a fraction of a second.

    Boom.

    Not Good.

    Stick with rated tanks.

    -Matt

  18. #18
    Join Date
    Jan 2004
    Location
    Halifax Nova Scotia
    Posts
    1,772
    Post Thanks / Like
    Likes (Given)
    4
    Likes (Received)
    249

    Post

    Where I am from the department of labor reqiures comercialy used air compressor tanks to be inspected on a regular interval . The inspection includes a ultra sound inspection of the bottom of the tank . I had a tank fail inspection because there were multiple pits detected that were .050" deep which is a significant portion of the original thickness.

  19. #19
    Join Date
    Dec 2005
    Location
    Kalispell, Montana
    Posts
    1,256
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    12

    Post

    There is a sealer out there that is used to "capture" rust in fuel tanks, put it in slosh it around and let it cure, never used it, guy at the radiator shop ( who also boils out fuel tanks) swears by it. The local Carquest store has in the "paint" portion of the store
    Jim

  20. #20
    Join Date
    Dec 2004
    Location
    Central IL, USA
    Posts
    1,181
    Post Thanks / Like
    Likes (Given)
    56
    Likes (Received)
    105

    Post

    I saw an air tank fail once. Well, the aftemath anyhow.

    The local tire company does mainly OTR truck tires and tractor tires. Well, they got a new F-350 and stuck an old re-worked service body on it. Only thing they didn't re-work was the receiver, an 80-gallon or so horizontal directly over the cab. The unloader valve on the compressor was set to 180PSI.

    Well, about three weeks went by with the new truck when the manager came in one morning to find half the windows in the small shop cracked or broken. Turned out that the tank had gone off sometime during the night and totalled the pickup. By totalled I mean stripped the cab and half the service body from the frame. Bent the frame several inches as well.

    Certainly makes me inspect my air tanks.


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •