what have i got

[BRR@PA]

hello all
came upon a steel tank that had been coated with the "dip it" plastic tool coating. I was able to remove the top layers and have a clean (appears to be galvanized) tank with the following codes.
mt dot-3aa 2250
hj 321083
(n in a diamond) 7 (n in a diamond) 73+ ( A with a line vert thru it)

no other re-hydro markings ? stamps. Has a valve but is empty.

Is this worth hydroing and using. And what cf or pressure is it.
thank you

 

[Scared Silly]

Ya got an old Norris LP72 that has been coated. The working pressure is 2250psi however that only gets ya 65cf. It you want to get the full 72 it needs to be overfilled by 10%. Which is what the "+" mark is after the year "73" in the hydro stamp. The next hydro will also need to have the "+" if you want to continue to overfill it.

Many take the coating off. As for worth using, sure. Get it hydro'd if it passes use it. Others will have some advise on removing the coating.

 

[halocline]

No, it's not worth testing or using, or even looking inside to see if it's clean. Feel free to send it to me (I'll pay shipping!) so I can dispose of it properly.

 

[JahJahwarrior]

Look inside. If it is coated inside, I wouldn't use it. Some people remove the coating but it tends to be a lot of work, I'd rather just buy another steel 72 somewhere for cheap. If it's only coated outside, then sure, strip that coating off and get it hydroed, 72s are great tanks!

 

[herman]

One other point, it is common for steel tanks to have some flash rust inside of them. As long as it's not bad it can be tumbled out, no big deal but something that may need to be done. Old 72s are still popular with a lot of divers. Well worth getting back in service. If it has a J valve on it, use it or there are plenty of us who would like to have it so don't trash it as most dive shops suggest.

 

[captain]

Look inside. If it is coated inside, I wouldn't use it. Some people remove the coating but it tends to be a lot of work, I'd rather just buy another steel 72 somewhere for cheap. If it's only coated outside, then sure, strip that coating off and get it hydroed, 72s are great tanks!

There is no valid reason not to use an interior coated tank. A good hydro shop knows what to look for. I have a couple that have always passed.