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Any good source for 16inch tower, chamber

Discussion in 'Compressors, Boosters and Blending Systems' started by Hoosier, Jun 20, 2009.

  1. Hoosier

    Hoosier Solo Diver

    I am looking for 16inch tower (chamber) for the portable filtration project.

    Please let me know if you have any good source.

    I prefer the used one though...

    Thanks in advance,
  2. frogman62

    frogman62 Barracuda


    I have new Bauer type filter (16in) chambers for $486 plus shipping
  3. Hoosier

    Hoosier Solo Diver


    I know where I can get the new one... It is about the same price range, even at eBay....

    I would like to get the used one first.. ;)
  4. CraigAClark

    CraigAClark Instructor, Scuba

    # of Dives: I'm a Fish!
    Location: South Florida
    Unless "used" filtration is attached to a compressor, you will not likely be able to verify the cycles it has seen. Since filtration towers are subject to a life span of cycles, I don't think it is a good idea to purchase used filtration, unless there is a verifiable history.

  5. Hoosier

    Hoosier Solo Diver


    Thanks for your comment. I haven't thought about that...:shocked2:

    So, what is a typical life span of the tower/chamber?:confused:

    As you may guess, I plan to use this one ONLY for the portable purpose. Whenever I go somewhere (NOT U.S.) I can't trust an air source, I plan to hook it up right before my tank inlet. Therefore, it won't be used that much compared to my static filtration system.

    The main reason that I am looking for 16inch & lighter unit is its dimension. I would like to put it into the pelican case.
  6. rcontrera

    rcontrera Dive Equipment Manufacturer

    You need one of these then.


    It is a standard Coltri tower with yoke inlet and outlet.
  7. Hoosier

    Hoosier Solo Diver


    Ray,,, I know yours. But, I am lazy so that I am looking for something that has a relatively longer filter life.... ;)
  8. iain/hsm

    iain/hsm Barracuda

    I think this is based on problems and some explosions of older pressure chambers built by Bauer and others that used a lower stress grade aluminium material and a lower 2.5:1 pressure to bust calculation rather than say the ASME 4:1 working pressure to burst ratio.

    So an old Bauer shell could have been made from 6061 or 6062 material and if built under TUV approvals only have a 2.5:1 WP to burst, (2 1/2 to 1) they also had on there separators a very high stress riser by using a sharp undercut on the thread lead out, that led to a number of explosions.

    The modern Bauer shells have a much greater radius on the thread lead out and are made from 7075 material so are now also 4:1 as far as WP to burst pressure, the same as most other modern filter shells.

    A lot of US fire departments got rid of their old Bauer shells so some of these do appear on E-bay from time to time and the like. As well as a number of oddball pressure accumulators and various cobbled together pressure bladders of low quality and poor trace ability. The trick is to know the difference.

    Filter life over in Europe for all filters including Bauer is based on pressure cycles and pressure reversals, so a filter going from 150 barg to 350 barg (2175 psig to 5000psig) as a chemical dehydrator will last longer by calculation than say a water separator that is going from zero pressure to full working pressure and back again 3 times an hour. Separator life is reduced by the pressure cycle in some cases at 3-4 cycles per hour on auto dump systems. 15 years life is common in Europe.
  9. iain/hsm

    iain/hsm Barracuda


    This is just more smoke and mirror rubbish. All the test results from these “personal filters” has ranged from grossly inadequate to totally useless for a number of reasons.
    Most of their problems are based on dwell time and gas velocity, resulting granted in some alterations to the outlet spigot hole diameter to reduce flow velocity in some later variants.

    However with these “personnel filters” from Coltri et al the basic idea is only to “polish” air that is already up to a breathing air standard, there is no capacity to handle air from a compressor that has failed air purity. Further there is no BPR back-pressure regulator and non-return valve so the shell is in effect filled and discharged of pressure very rapidly at each and every fill. When not in use the shell is stored empty of pressure, allowing the chemical to rapidly degrade.

    This causes two detrimental effects:
    1. It breaks down the chemical into powder or dust by the rapid decompression
    2. The lack of a BPR reduces the already inadequate amount of chemical to adsorb
    3. Coltri et al the suppliers fail to address the fact that oil particulate is adsorbed not absorbed so dirty long chain hydrocarbons adsorbed by the new chemical are simply desorbed back out into the next cylinder being charged.

    The advantages of using the original posters idea of a small standard size filter shell is obvious:

    1. Greater weight of, greter amount of, and greater volume of chemical.
    2. Lower gas velocity as the diameter of the pressure front is lowered by the greater diameter of the filter cartridge chemical.
    3. Longer dwell time as the length and diameter ratio of the standard 60 to 70 mm diameter cartridges is greater.
    4. Ability to filter air to a recognised breathing air standard even when the main compressor filter fails or is is totally spent for at least 12000 cu ft of process (with BPR) about 150 cylinder fills.

    IMHO this is the main reason why these products are called “Personnel Filter” it is frankly a bull**** statement They should be tested as filters under a recognised breathing air standard and not allowed to be sold to unsuspecting users. Or change the name to “Placebo Filter”. Just a thought LOL Iain Middlebrook
    Last edited: Jun 23, 2009

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