Steel tank ID

[Boiler_81]

I have a pair of steel PST tanks I need to ID. They were sold to me as 45s. However, they are not the 5.5" diameter tanks. The dimensions are 6.2" diameter and they are 21" long.

 

[oxyhacker]

A little more info, like pressure and other markings would be useful.

PST is said to have made some 3300 psi 72s that were 6.9" or so, and about 21" long.

Also there are a lot of industrial tanks that occasionally get misrepresented as scuba. The 72s mentioned above would have been galvanized, which industrial tanks rarely if ever were.

 

[Boiler_81]

They are marked
PST, DOT 3AA2015 Serial Numbers 1601K and 16054K

I do not see a working pressure stamped on them. My dive shop just did the visual on them and filled them to 2000 psi.

The dimensions are definitely 6.2" x 21". I measured the circumstance at 19.5 which is 6.2 diameter.

They painted white and have a US Divers Aqualung Sticker on them.

 

[Scared Silly]

The 2015 is the working pressure. What is the first hydro date?

 

[Boiler_81]

There is a stamp below the PST which I am having a hard time reading which appears to 9069+. The other hydro dates are 90, 95 and 09.

 

[Boiler_81]

 

[Kiwi303]

"9069+" means "September - proofers mark - 1969 manufacture - able to be filled to 10% over marked pressure" the O would be a stylised testers mark by the agency who first checked them.

 

[spectrum]

"9069+" means "September - proofers mark - 1969 manufacture - able to be filled to 10% over marked pressure" the O would be a stylised testers mark by the agency who first checked them.

The O could be an upper case C with an inscribed L for Cochran Labs which did a lot of PST hydros.

 

[Boiler_81]

I looked at the stamp again and I believe you are correct.

The O could be an upper case C with an inscribed L for Cochran Labs which did a lot of PST hydros.

 

[Boiler_81]

I have looked through the US Divers catalogs for 1968, 69 and 70. They only list 53s and 72s and nothing in white. I wonder if someone just stuck the US Divers stickers on them.