Old O2 cylinder

I'd think so. The US is a huge market for oxygen. Medical cylinders are the same as industrial cylinders. When I toured an Air Liquide Air separation facility they said welders are more fussy with having the purest oxygen than the medical community. It's all 99.6% or more pure and comes from the same bulk tank. I think Medical cylinders are more stringently tested.

I just picked this up yesterday from someone who saved it from going to scrap.

In that one, the symbol in question is left facing, and stamped 1927; they did not come to power until 1933 and even then I doubt their first edict was to start stamping gas cylinders

The backwards swastika appears to be a stamp from who ever certified the cylinder. It has 17 after it and the 4(-27) was stamped over the 17. It may be the original test date from the manufacturer. Can't see the name on the ring around the top. I can't remember if I've ever seen proper swastika's on a cylinder.

Crane Steel used that symbol on valves and flange fittings. They started manufacturing in the US, late 1880’s. First time I ran across that was on some riveted, bulk fuel storage tanks, at a decommissioned Chevron, WWII era tank farm, in SE Alaska. Which sparked my curiosity. Then, I learned about gas cylinders being marked that way.

Coaldust said: I’ve never seen an original, unmolested, German Linde bottle before with the swastika still in place. Most of them got re-stamped with a dash "-" punch to square the logo. Click to expand... Which makes what is referred to as a {Window Pane}. But as BV said--the direction of emblem is nothing more than a inspector stamp at one time, especially through the 20's. And the insignia is at least 12,000 years old with pottery that has been found roughly 7,000 years old. But it is a definite relic of that time period.

Today's bottle stamp of the day, this one is a window pane, post war it surely was not restamped but some company chose this as their emblem. Ring said Linde

A lot of cylinder rings are removeable so it's posible they could be changed. I don't know if all the window panes were originally backwards swastika's or not. It's possible companies merged and modified the stamp. It seems like oxygen producers have been buying each other out and/or merging for eons. It's a very lucrative industry with huge markup. It costs less than $10 to produce a large O2 cylinder yet they can sell for close to $100 in some places. The facility I toured said they make enough on argon everything else is gravy. Argon is only about 2% of the atmosphere!

stinky64 said: Don't think ancient civilizations were stamping oxygen bottles. Click to expand... stinky64 said: Don't think ancient civilizations were stamping oxygen bottles. Click to expand... Tanks like we have now existed before the Nazi party.

materthegreater said: I just picked this up yesterday from someone who saved it from going to scrap. View attachment 321884 Click to expand... Turns out this tank was full. Glad it didn't go to scrap.

Well 3/4's full anyway and you don't have to worry if the O2 is old. It has no expiry date.

Actually I believe this one is tri-mix. I've never seen one come with much more than 2000psi

Do you know what that specific gas mix is used for? I'm pretty sure for a wire feed process but not sure what wire, thinking maybe stainless? If the cylinder has been sitting around for awhile it's a good idea to lay it on its side and roll it around for a minute or so. Some mix gases will seperate. Some rather quickly. When I toured a fill plant they had a cylinder roller for mixing specialty gases.

The label doesn't give percentages, but it lists the same gases as my other tri-mix tank that I use for stainless. I tried this on some non critical parts with my Hobart 140 and it seemed to work fine, but I don't have much experience welding stainless. Thanks for the suggestion, I'll try rolling it around a bit.