Vintage Tank find

[CT-Rich]

i found this twin set of tanks at an estate sale today. I was hoping the collective might help me out and confirm a few things. This is what I already have determined, I may be wrong on some details, corrections greatly appreciated.
The tanks are German(the sides are labeled “Atemluft” -breathing gas)
They have a couple of hydro stamps (I think they are variously 62 and 71)
I think the born on date is 1957 (if you know how to read the stamps, let me know)
They are 7 liter/ 200 bar, making them 49 ft3 each.
They are currently empty (0 psi)
I am not sure if they are aluminum or steel, if you know, post it.
Currently, the plan is to keep them on the porch with my other diving collectibles, but what is the likelihood I could get them serviced and divable? Are they of any collectible value or just interesting curiosities?

 

[2TH DIVR]

Hydro's will be a problem being German with out ICC or DOT stamps.
You might find someone to hydro them and see if they pass but won't stamp them.
If you have access to a compressor you'd be OK.

 

[tursiops]

Almost surely steel, given the round bottoms and narrow necks.

 

[happy-diver]

Diving cylinder - Wikipedia

 

[CT-Rich]

Almost surely steel, given the round bottoms and narrow necks.

I was pretty sure they were steel. I took a look at the harness, it looks like it may have been close to new, so probably early 70s or late 60s.

 

[AfterDark]

Get a magnet if it sticks it's steel. Rich did you buy these tanks? I couldn't get a straight answer from you yesterday. I still don't know if you are buying them or selling them.

For old steel tanks not one hint of rust. With K valves they'd make dandy IDs!

 

[michael-fisch]

Looks like the outside was galvanized, and is in perfect condition. They were made by IWK "Industrie Werke Karlsruhe" in Bexbach and are really good lightweight tanks made of very high quality steel.
Min Burst Pressure when new was specified to be over 800Bar, Hydro test Pressure is 300Bar but many divers regularily fill them to 260Bar cold and I haven't heard of people dieing because of these tanks exploding.
Really top quality tanks, usually sold to fire departments, for use above water, and the military. They were usually phased out after the fire departments upgraded to 300Bar systems.
The valves are commonly known as "Kleinkonische Ventile", the actual specification is "W 19,8 × 1/14 keg DIN 477 ISO 11363 – 17E".

For gods sake, don't cut these tanks and make bells/windchimes out of them - there are enough vintage divers who have been looking for a good set for over 5 years and pay cash.
Vintage divers will love them and dive them for another 50 or 75 years.
Should be worth a few hundred dollars to someone needing tanks for his antique Mistral or Royal Mistral regulator.

Michael

 

[happy-diver]

Learning inside do not OPEN

 

[Compressor]

View attachment 533588
i found this twin set of tanks at an estate sale today. I was hoping the collective might help me out and confirm a few things. This is what I already have determined, I may be wrong on some details, corrections greatly appreciated.
The tanks are German(the sides are labeled “Atemluft” -breathing gas)
They have a couple of hydro stamps (I think they are variously 62 and 71)
I think the born on date is 1957 (if you know how to read the stamps, let me know)
They are 7 liter/ 200 bar, making them 49 ft3 each.
They are currently empty (0 psi)
I am not sure if they are aluminum or steel, if you know, post it.
Currently, the plan is to keep them on the porch with my other diving collectibles, but what is the likelihood I could get them serviced and divable? Are they of any collectible value or just interesting curiosities?
View attachment 533588

WOW; a great find. Congratulations.

 

[AfterDark]

Learning inside do not OPEN

Rich, you definitely want to open this link.