AIR: dive tanks storage and servicing

[flynny]

hey guys

me and the team i play i for have all converted to air now and are now looking into storing our own air.

i know SCUBA tanks are the way forward but from there i am a little in the dark.

so any information on everything from which type, capacity, pressure and servicing will be very well received!

well there you go, educate me please!

flynny

 

[Bob]

They larger the better realy bu it depend on how much you need and any weight restrictions.

12L 310 bar tanks are probly the best as they have a large capacity and aluminium, you can get 15L steel tanks which would get a few extra full fills but they are alot heavier.

Try your local dive shop (yell.com or yellow pages) and drop in of phone them and they will explain the ins and outs of them. They may also have 2nd hand dive tanks for sale in which case it would be one of the best places to buy them.

Don't forget that you need a fill rig to fill your bottles and that it must have the same fitting and pressure rating as the tank.

 

[arg1271]

Dive tanks come in a wide variety of sizes but predominatley two 'working' pressures:

232 bar (about 3000 psi) and 300 bar (about 4500psi) there are converters out there for exact figures.

Tanks will also have one of two fittings, a-clamp/yoke or DIN, DIn is typically used on the 300bar tanks.

Depending on the gas consumption of your marker, the bottle size on your marker and how many shots you're firing you could get a day's play out of a 12litre @ 232bar. though one of the most common setup's is to have one or more tanks to use for bulk filling and then another tank to top the pressure up.

As is where to buy, yep either you local dive shop or club, or you could try the scuba diveing websites as many have classified forums. Dive tanks are subject to testing as well, every 2.5 years a visual test (about £20) and every 5 years a hydrostatic test (about £25) unless they are specifically for surface use whereby I think it's a 5 year test span but they can last for many years unlike the 15 year 'life' on most fibrewrap bottles.

hope that clears things up

 

[Tom Allen]

207 bar is 3000psi

232 bar is 3500psi

310 bar is 4500psi

1 bar is 14.5 psi


hope this helps...

 

[Revolt]

slightly off topic, does having your 1.1 air tank filled to max (4.5k) and leaving it like that for months... will it weaken the tank ?

 

[Tom Allen]

you could leave it for twenty years and it would still be perfect

 

[Tom Allen]

tank would be out of test by then though...

 

[Revolt]

thanks for giving me peace of mind

 

[arg1271]

it's better to leave them with some pressure in at all times anyway, especially if you have angel AIR !!

 

[Skeet]

You wont typically find 300bar tanks at dive shops...because most divers dont use them due to the weight, fact.

Also fact I believe, is that 12L 300bar tanks are usually made of steel, not aluminium.

It is not adviseable to retro fit an A-Clamp fitting onto a 300bar DIN tank, as A-Clamps are commonly only rated for 207-232 bar...not 300bar.

Dive tanks have a periodic testing of 2.5 years, with alternate Hydro testing and Visual testing.

Tanks fitted with a DRY valve, ie, not a Scuba valve...can be obtained and are subject to 5 year test schedules.

Writing "Surface Use Only" on your Scuba tank, does not prevent it from requiring 2.5 year tests.

Do not place a full dive tank in a sharks mouth and shoot it with a high velocity rifle, unless it is safe to do so and no by standers will be affected, or unless it is in an emergency.