tank markings......

[The Horn]

I can't seem to get a measurement to mathch that of the current PST charts but the closest ank I do get is an LP-80?

Tank measures 6.9" in diameter outside and is roughly 24" long from the bottom to the point where it necks for the valve threads.

All things considered they outwordly look in good condition and I hope the insides are not all messed up.

Would these make a decent twin setup if they are good to go?

 

[Scared Silly]

Sounds like a 72 ... People do double these up as a nice set of small doubles. I certainly would do it. (I have doubles Al80s.)

 

[The Horn]

Will send them out to see what is what. I sent info in to PST but got a "e-mail address no good" from thier website?

Yes they do sound like a 72 but the measurements throw things off a bit. Did some calculations and they fit the 72 bill.

Hopefully they work out and perhaps a set of doubles they will make!!!

 

[SDAnderson]

Will send them out to see what is what. I sent info in to PST but got a "e-mail address no good" from thier website?

PST is more or less dead. The company went bankrupt and there are efforts afoot to resurrect the scuba cylinder business but, so far, they aren't making tanks. The successor company website is www.pstscuba.com, they may be able to help you with any questions you have.

The cylinders you have are almost certainly 72's. PST didn't mark most of their tanks with size information, so you're going to have to guess based upon dimensions, pressure rating and manufacture date. Most RIN facilities will have the information they need in order to test the cylinders and should, if you ask and if the tanks pass the test, be able to give you a plus rating.

They'll work just fine as a small set of doubles.

 

[Luis H]

As it has been mentioned, they are almost certain steel 72.

Here are some specifications.
This data came from one of my US Divers 1970's maintenance and repair manuals:

72 cu ft Standard

Service pressure, psi : 2250
Actual air capacity, ft3 (at 2475 psi): 71.55
Outer diameter, in: 6.81 (most are closer to 6.9")
Length without valve, in: 25.12
Empty weight, lbs (w/o valve): 26
Buoyancy Empty, lbs (w/valve): 0
Buoyancy Full, lbs (w/valve): -5.4

The length is measure to the top of the neck. The length can vary quite a bit from tank to tank. I own about 12 of them and they are not all the same length. One is particularly taller then the rest.

Good luck

 

[oxyhacker]

No special information is necessary to do the basic hydro on these tanks, so any hydro shop can do it.

Getting the plus is more complicated, for the 72 especially, since very few shops seem to know how to do it. There was a very thorough Plus Hydro thread on thedecostop very recently that has all the details.

And they do make lovely small doubles!

Most RIN facilities will have the information they need in order to test the cylinders and should, if you ask and if the tanks pass the test, be able to give you a plus rating.

They'll work just fine as a small set of doubles.

 

[rjack321]

Is it even possible to really do a proper plus on a 72 anymore??
Since:
1) nobody seems to have an REE for them
2) sizes and presumably wall thickness seems to vary so much if you had a smart enough requalifier to run through the math they don't have the info they need to input to the formula

I presume all the recent pluses I see on 72s without REEs are somewhat vaporous.

 

[jduncan]

In fact I believe many steel tanks today still don't have cf markings, especially the Faber LP series but I could be wrong. Can anyone confirm?
I know the Worthington X-series and the PST E-series have cf markings.

FWIW....I just borrowed a Faber LP 72 and it's marked 3000. I didn't see any CF designations.