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Tank valves

Discussion in 'Tanks, Valves and Bands' started by Frog, May 24, 2001.

  1. devjr

    devjr Manta Ray

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    Frog, a 15 liter is a huge tank. No, a 100 cf is not the same as a 15 liter which will hold 120cf @ 232 bar. A 15 liter @ 180 bar will hold 95cf. Multiply the tank volume(L) by 232 or 180, and to get the capacity in cf, divide the result by 28.3.
     
  2. Frog

    Frog Barracuda

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    Well thanks alot for the lowdown Warhammer. The backplate weighs 6Lbs. I only dive dry. At the moment i have around 10-12 kgs of lead in my Intergrated BCD. This is with a Steel 12L Cylinder. By the way DevJr 12L steels are usually standard issue around this area (in Great Britain). I'm not a largest of men either..only around 5'8" and 11 and a half stones in weight (about 170 lbs?). So i have already shed 6lbs of lead due to the SS backplate. If i ever manage to go diving abroad again then i would se an aluminium backplate with a wet suit. My Reg set weighs approx 2.5kg as well, so thats more none ditchable weight. I cant think of anything else i would use on a dive on a regular basis(for now) other than a small knife and a few bolt snaps.
    Cheers
     
  3. Lost Yooper

    Lost Yooper Loggerhead Turtle

    # of Dives: I'm a Fish!
    Location: Panama City Beach, FL
    2,082
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    Frog,

    If you want to use an A-clamp on a DIN valve, you have to get a 200 BAR DIN valve and put the yoke insert into it. A 300 BAR DIN valve is too big for the A clamp.
    I beleive you would be better off with the H-valve so that you keep things modular.

    Mike
     
  4. BetterLateThannever

    BetterLateThannever Barracuda

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    Walter,LY,Frog,

    The room is spinning around me. Y'all must have taken a different course than I did. The PADI OW class didn't cover any of this stuff. Where do I go to get more knowledgeable about the intricacies of diving you are discussing? Is there a place that systematically lays out, in laymen's terms, subject matter of; tanks, weights and weight distribution, regulators and valve options, etc.etc.

    Jimbo
     
  5. Lost Yooper

    Lost Yooper Loggerhead Turtle

    # of Dives: I'm a Fish!
    Location: Panama City Beach, FL
    2,082
    5
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    Don't get me started on training agencies as I don't have much good to say about most of them. IMO, the best source of information is through the WKPP and the leaders of GUE. If you want to learn at a rapid pace, subscribe to the GUE Quest newsgroup. Ask your questions with an open mind and take it in like a sponge. Arguing with them won't get you far, but they are very open to those wanting to learn from them. The last link is DIR videos -- really cool.

    http://www.gue.com
    http://www.wkpp.org
    http://www.sfdj.com/dive/dir1.htm

    Hope it helps.

    Mike
     
  6. Warhammer

    Warhammer Manta Ray

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    One more consideration, Frog. If you're going DIR all the way, and I'm the last person that should be preaching DIR but what the hell, you'll need a canister light. That light will also have negative bouyancy further reducing the weight on your belt. While it is ditchable weight, it's a mighty expensive piece of ditchable weight. :)
     
  7. Frog

    Frog Barracuda

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    LOL! Heh Warhammer. Nah i am not going DIR "all the way". I am just basing my gear around DIR ideas which make sense to me thats all.
     
  8. Frog

    Frog Barracuda

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    BetterLateThanNever. This is a hot potato - agencies i mean. But here go's. Personally i did PADI OW and AOW. I havnt trained with any other agency YET but will be going on a few IANTD courses soon. I leanrned 99% of what i know by reading on web sites and i will be very glad to give you as many links as i can find. What i learned from my PADI training, was in my opionion, JUST the basics whcih allowed me to dive. My instructor and the people associated with the diving shop with whcih i took my courses where only after my money and i sniffed this out pretty early on, although i did my certs anyway, but thats another story. I went from reading basic things like on divernet and rodales scubadiving.com. Bear in mind though that i am a student with alot of time on my hands so all i tend to do is read about diving. Basically i came to the conclusion after months of reading day in day out night in night out, that DIR is the way to go for me. For you it may be different depending ultimately on what kind of diving you wish to do. I have seen many photographs of the springs/caves in Florida and from seeing the caves for the first time i knew that i wanted to dive them so thats something that will happen in the future - no doubt. However, i am not under any illusions, i am still a BEGINNER, experience is the most valuble thing here and that cannot be rushed by any means. Anyway here are some great links, and i hope they help you on your way. Starting with the recreational type sites:

    http://www.scubadiving.com/
    http://www.divernet.co.uk
    http://www.ukdiving.co.uk/ukdiving.htm (click on new equipment)
    http://www.gasdiving.co.uk/
    http://www.wkpp.org/
    http://gue.com/index.html
    http://www.dis-uk.org/
    http://www.dir-uk.org/
    http://www.fifthd.com/gear/
    http://www.h2oadventuregear.com/index.html
    http://www.techdiving.org/
    http://www.ping.be/safe-diving/DIR2.htm
    http://www.990mag.co.uk/
    http://www.scu.edu.au/schools/rsm/staff/pages/shartley/projects/gear/
    http://www.halcyon.net

    Cheers




     
  9. devjr

    devjr Manta Ray

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    Frog, you asked about overpressuring tanks. It depends on several things. We are discussing a new, never used tank.

    Since PST tanks are unavailable to you, we can dispense with discussion of those and that is just as well. However, Faber/Italy tanks are available in UK under different brand names including "Aqualung". I cannot, of course, recommend that you or anyone overpressurize a tank. However, I have observed that the Faber LP (180 bar) tank is sometimes overpressurized here in the US. The usual terminal pressure is about 200 bar.

    Available literature in the US characterizes this tank as rated for 2400+ psi(DOT) meaning a terminal pressure of 2640. However, the literature goes on to say that the burst pressure of this tank is 6500psi; furthermore, the tank is capable of "10,000 cycles at 4000 psi", equivalent to 270 bar.

    You can draw your own conclusions. I don't know the laws and customs in your area. In the US, it is unlawful for a "common carrier" (lorry) engaged in interstate commerce to transport an overpressurized tank. However,I've never heard of this law being enforced and it doesn't appear to apply to private use anyway. Beyond this, it makes sense to be prudent in the handling and use of high pressure cylinders. That means no abuse, no excess temperatures and an appropriate burst plug installed, if required. The standards and requirements for high pressure cylinders are understandably conservative and stringent as the originators of the codes have no control over the many factors which affect the cylinders.



     
  10. Lost Yooper

    Lost Yooper Loggerhead Turtle

    # of Dives: I'm a Fish!
    Location: Panama City Beach, FL
    2,082
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    Ask yourself where the weak link is in the tank -- the O-ring in the neck. What's going to happen first? Either the tank will explode or the o-ring will fail. Taking any guesses which will occur first? Another thing is, will tank explode before the compressor maxes out. I'm not a compressor expert, but I hear most compressors can't pump beyond the limits of steel tanks though I certainly could be wrong here.
    Steel tanks are regulary over filled to 3500psi so long as the disks are plugged or have additional shims put in. I pump my PS 95's to 3200psi and let them cool to 3000. Common sense can go a long way, but do whatever you're comfortable with -- just keep them in hydro. The hardest part is finding a shop that will do it, but those that know better will do it.

    Later,

    Mike
     

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