LP 72's

[halocline]

If these are NZ tanks, what are the markings? Does it still say 3AA 2250, obviously not ICC or DOT. I'm curious about it. I have heard somewhere that European tanks that are the equivalent of 2400 PSI LP tanks here are just rated for 2640, or equal to the + rating here. I have no idea if that's true, but if these are something along those lines I guess they be 2475.

I would gladly fill mine to 2800-3000 every day if I could get someone to do it. I usually can't, but 2500 is pretty typical. They almost never fail hydro, maybe because the test pressure is only 3750, whereas its 4000 for modern 3AA 2400PSI tanks.

 

[Packhorse]

Anyone use these as deco tanks?

 

[DA Aquamaster]

I have heard a few people who use them as deco tanks, and a long time ago, I used to use them under the boat as safety tanks, but they are not a great choice for a tank you plan to keep with you.

 

[Packhorse]

Why is that?
Seems they have similar buoyancy characteristics to ali 80s while slightly smaller.

 

[elan]

If these are NZ tanks, what are the markings? Does it still say 3AA 2250, obviously not ICC or DOT. I'm curious about it. I have heard somewhere that European tanks that are the equivalent of 2400 PSI LP tanks here are just rated for 2640, or equal to the + rating here. I have no idea if that's true, but if these are something along those lines I guess they be 2475.

I would gladly fill mine to 2800-3000 every day if I could get someone to do it. I usually can't, but 2500 is pretty typical. They almost never fail hydro, maybe because the test pressure is only 3750, whereas its 4000 for modern 3AA 2400PSI tanks.

not sure about the European tanks but Canadian LPs are marked as 184/2400 which means in Canada we can get 184 bar in them which is the same as 2400+ rating in the US. So say if you hydro the LP tank having this marking you do not loose the "+ rating as it does not exist"

 

[elan]

Why is that?
Seems they have similar buoyancy characteristics to ali 80s while slightly smaller.

Well ~4lb difference is far from being similar Empty AL80 is just a bit positive (with the reg and SPG on) and can in fact swim up on it's own while empty LP72 is negative when empty. You can go even further, many prefer Luxfers over Catalinas for Catalinas being tail heavy. Though they have similar positive buoyancy.

 

[Packhorse]

The USD ones say DOT 3AA2250 and the seem to be internally coated but in OK condition. Cant clearly make out the markings on the Healtways

 

[Packhorse]

Oh, I twinned them up using faber 12L sized bands and ended up with 225mm centres ( standard is 216mm)

 

[halocline]

I'm not sure about the 12L size bands, but I did notice trying to use 7.25" bands on my LP72s did not work out well, and it did push the tanks further apart. That's because the flanges that the bolts go through are closer together, meaning more on the "center" of the tanks, looking top to bottom through a cross-section. I then tried 7" bands and it worked fine. I do notice that with a standard iso manifold (blue steel) there are a few more threads showing than I would have expected.

Out of curiosity, what happens when you try to get DOT tanks hydro'ed in NZ? Are the testing facilities used to seeing U.S. tanks?

 

[captain]

Here are bands for 72's. They are reproductions of the old Aqua Lung bands. They have the slots for the web type harness. The spacing is 8 & 1/8" give or take a 1/16".

http://cgi.ebay.com/Vintage-Repro-N...emQQptZLH_DefaultDomain_0?hash=item2eab9fd77c