Small tank question / solicitation

[Luis H]

I have a couple of vintage Drager tanks (1957) and yes they are German and metric.

I hope yours is not metric, but I would be a bit surprised. Some modern DIN valves are convertible, but not the vintage DIN valves.


I can only wish you the best of luck.

 

[8dust]

Thanks for the well wish Luis.

Supposed to be born in 2000.

Have you seen an insert for the valve?

I did some more looking and that seems to be a way some are coming now a days, but have not found a place to buy just the insert. Thoughts?

 

[Slonda828]

Thermo valves and several others come convertible. They are the 5 thread DIN, what lay people call "200 bar DIN". The dedicated DIN ones that are not convertible are 7 thread, what lay people call "300 bar DIN". There is no difference in the amount of pressure that either on of those DIN valves can hold, so calling them that is kind of inexact. Really as long as the regulator is rated to the pressure you are using and you have the appropriate burst disk you are aces. It's not like "300 bar DIN" valves are made out of a different material or anything. I would suggest that if you call John at Northeast Scuba Supply, he has all kinds of stuff. I bet he has DIN conversion plugs for thermo valves. I am not sure how they fit in relation to your drager valve, but one can only try. Worst case scenario sell it to some European diver. They are easy to pick out because they wear wheenie bikinis under their drysuits LOL.

 

[coldwaterlloyd]

Can anyone confirm these are 50 cu ft ?
DOT - SP6498-3000

 

[AfterDark]

Can anyone confirm these are 50 cu ft ?
DOT - SP6498-3000

Not from those pictures. We need to see the stamping on the neck. If it's 1800psi they are probably 50's. They do however look old enough to be made from a questionable type of AL alloy that tends to crack and a lot of LDS will not fill.

 

[herman]

They appear to be 50's .
The 74 catalog shows aluminum cylinders available that year in 50 and 80 cf with the same decals. According to the catalog, the 50 was 6.9 inches in diameter and 21.8 in tall, weighing 24 lbs.
Unfortunately, the SP6498 is the al alloy that was giving problems so it's going to be a problem finding a shop that will fill them. Sad since they make a nice set of vintage doubles. You can find the catalog on Vintage Double Hose.

 

[Luis H]

Can anyone confirm these are 50 cu ft ?
DOT - SP6498-3000

The numbers show they are 3000 psi. They are also "Special Permit" 6498. They are aluminum alloy 6351, which is prone to sustain load cracking. They can be inspected and will require eddy current testing.

I would retire them. The required inspection are going to cost you extra and many dive shops will not fill them. I would not fill them.

The Mk II sticker means they are indeed 50 cu ft. The firs catalog these cylinders show up in is the US Divers 1973 catalog. They continue to show up in all the later 1970's catalogs and I also see them in the 1983 catalog. That is the last catalog I have.

 

[Luis H]

They appear to be 50's .
The 74 catalog shows aluminum cylinders available that year in 50 and 80 cf with the same decals. According to the catalog, the 50 was 6.9 inches in diameter and 21.8 in tall, weighing 24 lbs.
Unfortunately, the SP6498 is the al alloy that was giving problems so it's going to be a problem finding a shop that will fill them. Sad since they make a nice set of vintage doubles. You can find the catalog on Vintage Double Hose.

The 80 had the "Professional" decal. Page 7 of 1974 catalog.
The 71.2 aluminum had a "Mk I" decal. Page 8 of 1974 catalog
The 50 aluminum had the "Mk II" decal. Page 9 of the same catalog.

I know it is early